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Sync up with master #7

Merged
merged 165 commits into from
Nov 15, 2014
Merged

Sync up with master #7

merged 165 commits into from
Nov 15, 2014

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dabrace
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@dabrace dabrace commented Nov 15, 2014

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horms and others added 30 commits October 27, 2014 09:03
Unlike other SATA R-Car r8a7790 controllers the r8a7790 ES1 SATA R-Car
controller needs to be run with DIPM disabled.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
This reverts commit 33fb0d0.

18dcf43 ("AHCI: Optimize single IRQ interrupt processing") is
scheduled to be reverted.  This is an optimization dependent on the
mentioned commit.  Revert it first.

Signed-off-by: Tejun Heo <tj@kernel.org>
This reverts commit 18dcf43.
IRQF_ONESHOT was missing from the conversion causing screaming
interrupts problems on some setups and LKP detected measureable drop
in IO performance.  It looks like we'll first need to drop the
threaded IRQ handling first before splitting locking.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Reported-by: kernel test robot <fengguang.wu@intel.com>
Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/g/20141027021651.GF27038@yliu-dev.sh.intel.com
Link: http://lkml.kernel.org/g/1414082970-20775-1-git-send-email-marc.zyngier@arm.com
Samsung pci-e SSDs on macbooks failed miserably on NCQ commands, so
67809f8 ("ahci: disable NCQ on Samsung pci-e SSDs on macbooks")
disabled NCQ on them.  It turns out that NCQ is fine as long as MSI is
not used, so let's turn off MSI and leave NCQ on.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=60731
Tested-by: <dorin@i51.org>
Tested-by: Imre Kaloz <kaloz@openwrt.org>
Cc: stable@vger.kernel.org
Fixes: 67809f8 ("ahci: disable NCQ on Samsung pci-e SSDs on macbooks")
This patch adds the AHCI-mode SATA Device IDs for the Intel Sunrise Point PCH.

Signed-off-by: James Ralston <james.d.ralston@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Koji Matsuoka <koji.matsuoka.xm@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
mvm->cur_ucode wasn't set before we actually load the
firmware. This caused issues when we boot in RFKILL since
we get an RFKILL interrupt upon boot even before we load
any firmware.
This leads to issues since iwl_mvm_set_hw_rfkill_state
(the RFKILL interrupts handler in mvm) relies on this
variable.

Fix this.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
The driver is not released when ieee80211_register_hw fails in
mac80211_hwsim_create_radio, leading to the access to the unregistered (and
possibly freed) device in platform_driver_unregister:

[    0.447547] mac80211_hwsim: ieee80211_register_hw failed (-2)
[    0.448292] ------------[ cut here ]------------
[    0.448854] WARNING: CPU: 0 PID: 1 at ../include/linux/kref.h:47 kobject_get+0x33/0x50()
[    0.449839] CPU: 0 PID: 1 Comm: swapper Not tainted 3.17.0-00001-gdd46990-dirty #2
[    0.450813] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    0.451512]  00000000 00000000 78025e38 7967c6c6 78025e68 7905e09b 7988b480 00000000
[    0.452579]  00000001 79887d62 0000002f 79170bb3 79170bb3 78397008 79ac9d74 00000001
[    0.453614]  78025e78 7905e15d 00000009 00000000 78025e84 79170bb3 78397000 78025e8c
[    0.454632] Call Trace:
[    0.454921]  [<7967c6c6>] dump_stack+0x16/0x18
[    0.455453]  [<7905e09b>] warn_slowpath_common+0x6b/0x90
[    0.456067]  [<79170bb3>] ? kobject_get+0x33/0x50
[    0.456612]  [<79170bb3>] ? kobject_get+0x33/0x50
[    0.457155]  [<7905e15d>] warn_slowpath_null+0x1d/0x20
[    0.457748]  [<79170bb3>] kobject_get+0x33/0x50
[    0.458274]  [<7925824f>] get_device+0xf/0x20
[    0.458779]  [<7925b5cd>] driver_detach+0x3d/0xa0
[    0.459331]  [<7925a3ff>] bus_remove_driver+0x8f/0xb0
[    0.459927]  [<7925bf80>] ? class_unregister+0x40/0x80
[    0.460660]  [<7925bad7>] driver_unregister+0x47/0x50
[    0.461248]  [<7925c033>] ? class_destroy+0x13/0x20
[    0.461824]  [<7925d07b>] platform_driver_unregister+0xb/0x10
[    0.462507]  [<79b51ba0>] init_mac80211_hwsim+0x3e8/0x3f9
[    0.463161]  [<79b30c58>] do_one_initcall+0x106/0x1a9
[    0.463758]  [<79b517b8>] ? if_spi_init_module+0xac/0xac
[    0.464393]  [<79b517b8>] ? if_spi_init_module+0xac/0xac
[    0.465001]  [<79071935>] ? parse_args+0x2f5/0x480
[    0.465569]  [<7906b41e>] ? __usermodehelper_set_disable_depth+0x3e/0x50
[    0.466345]  [<79b30dd9>] kernel_init_freeable+0xde/0x17d
[    0.466972]  [<79b304d6>] ? do_early_param+0x7a/0x7a
[    0.467546]  [<79677b1b>] kernel_init+0xb/0xe0
[    0.468072]  [<79075f42>] ? schedule_tail+0x12/0x40
[    0.468658]  [<79686580>] ret_from_kernel_thread+0x20/0x30
[    0.469303]  [<79677b10>] ? rest_init+0xc0/0xc0
[    0.469829] ---[ end trace ad8ac403ff8aef5c ]---
[    0.470509] ------------[ cut here ]------------
[    0.471047] WARNING: CPU: 0 PID: 1 at ../kernel/locking/lockdep.c:3161 __lock_acquire.isra.22+0x7aa/0xb00()
[    0.472163] DEBUG_LOCKS_WARN_ON(id >= MAX_LOCKDEP_KEYS)
[    0.472774] CPU: 0 PID: 1 Comm: swapper Tainted: G        W      3.17.0-00001-gdd46990-dirty #2
[    0.473815] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    0.474492]  78025de0 78025de0 78025da0 7967c6c6 78025dd0 7905e09b 79888931 78025dfc
[    0.475515]  00000001 79888a93 00000c59 7907f33a 7907f33a 78028000 fffe9d09 00000000
[    0.476519]  78025de8 7905e10e 00000009 78025de0 79888931 78025dfc 78025e24 7907f33a
[    0.477523] Call Trace:
[    0.477821]  [<7967c6c6>] dump_stack+0x16/0x18
[    0.478352]  [<7905e09b>] warn_slowpath_common+0x6b/0x90
[    0.478976]  [<7907f33a>] ? __lock_acquire.isra.22+0x7aa/0xb00
[    0.479658]  [<7907f33a>] ? __lock_acquire.isra.22+0x7aa/0xb00
[    0.480417]  [<7905e10e>] warn_slowpath_fmt+0x2e/0x30
[    0.480479]  [<7907f33a>] __lock_acquire.isra.22+0x7aa/0xb00
[    0.480479]  [<79078aa5>] ? sched_clock_cpu+0xb5/0xf0
[    0.480479]  [<7907fd06>] lock_acquire+0x56/0x70
[    0.480479]  [<7925b5e8>] ? driver_detach+0x58/0xa0
[    0.480479]  [<79682d11>] mutex_lock_nested+0x61/0x2a0
[    0.480479]  [<7925b5e8>] ? driver_detach+0x58/0xa0
[    0.480479]  [<7925b5e8>] ? driver_detach+0x58/0xa0
[    0.480479]  [<7925b5e8>] driver_detach+0x58/0xa0
[    0.480479]  [<7925a3ff>] bus_remove_driver+0x8f/0xb0
[    0.480479]  [<7925bf80>] ? class_unregister+0x40/0x80
[    0.480479]  [<7925bad7>] driver_unregister+0x47/0x50
[    0.480479]  [<7925c033>] ? class_destroy+0x13/0x20
[    0.480479]  [<7925d07b>] platform_driver_unregister+0xb/0x10
[    0.480479]  [<79b51ba0>] init_mac80211_hwsim+0x3e8/0x3f9
[    0.480479]  [<79b30c58>] do_one_initcall+0x106/0x1a9
[    0.480479]  [<79b517b8>] ? if_spi_init_module+0xac/0xac
[    0.480479]  [<79b517b8>] ? if_spi_init_module+0xac/0xac
[    0.480479]  [<79071935>] ? parse_args+0x2f5/0x480
[    0.480479]  [<7906b41e>] ? __usermodehelper_set_disable_depth+0x3e/0x50
[    0.480479]  [<79b30dd9>] kernel_init_freeable+0xde/0x17d
[    0.480479]  [<79b304d6>] ? do_early_param+0x7a/0x7a
[    0.480479]  [<79677b1b>] kernel_init+0xb/0xe0
[    0.480479]  [<79075f42>] ? schedule_tail+0x12/0x40
[    0.480479]  [<79686580>] ret_from_kernel_thread+0x20/0x30
[    0.480479]  [<79677b10>] ? rest_init+0xc0/0xc0
[    0.480479] ---[ end trace ad8ac403ff8aef5d ]---
[    0.495478] BUG: unable to handle kernel paging request at 00200200
[    0.496257] IP: [<79682de5>] mutex_lock_nested+0x135/0x2a0
[    0.496923] *pde = 00000000
[    0.497290] Oops: 0002 [#1]
[    0.497653] CPU: 0 PID: 1 Comm: swapper Tainted: G        W      3.17.0-00001-gdd46990-dirty #2
[    0.498659] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    0.499321] task: 78028000 ti: 78024000 task.ti: 78024000
[    0.499955] EIP: 0060:[<79682de5>] EFLAGS: 00010097 CPU: 0
[    0.500620] EIP is at mutex_lock_nested+0x135/0x2a0
[    0.501145] EAX: 00200200 EBX: 78397434 ECX: 78397460 EDX: 78025e70
[    0.501816] ESI: 00000246 EDI: 78028000 EBP: 78025e8c ESP: 78025e54
[    0.502497]  DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068
[    0.503076] CR0: 8005003b CR2: 00200200 CR3: 01b9d000 CR4: 00000690
[    0.503773] Stack:
[    0.503998]  00000000 00000001 00000000 7925b5e8 78397460 7925b5e8 78397474 78397460
[    0.504944]  00200200 11111111 78025e70 78397000 79ac9d74 00000001 78025ea0 7925b5e8
[    0.505451]  79ac9d74 fffffffe 00000001 78025ebc 7925a3ff 7a251398 78025ec8 7925bf80
[    0.505451] Call Trace:
[    0.505451]  [<7925b5e8>] ? driver_detach+0x58/0xa0
[    0.505451]  [<7925b5e8>] ? driver_detach+0x58/0xa0
[    0.505451]  [<7925b5e8>] driver_detach+0x58/0xa0
[    0.505451]  [<7925a3ff>] bus_remove_driver+0x8f/0xb0
[    0.505451]  [<7925bf80>] ? class_unregister+0x40/0x80
[    0.505451]  [<7925bad7>] driver_unregister+0x47/0x50
[    0.505451]  [<7925c033>] ? class_destroy+0x13/0x20
[    0.505451]  [<7925d07b>] platform_driver_unregister+0xb/0x10
[    0.505451]  [<79b51ba0>] init_mac80211_hwsim+0x3e8/0x3f9
[    0.505451]  [<79b30c58>] do_one_initcall+0x106/0x1a9
[    0.505451]  [<79b517b8>] ? if_spi_init_module+0xac/0xac
[    0.505451]  [<79b517b8>] ? if_spi_init_module+0xac/0xac
[    0.505451]  [<79071935>] ? parse_args+0x2f5/0x480
[    0.505451]  [<7906b41e>] ? __usermodehelper_set_disable_depth+0x3e/0x50
[    0.505451]  [<79b30dd9>] kernel_init_freeable+0xde/0x17d
[    0.505451]  [<79b304d6>] ? do_early_param+0x7a/0x7a
[    0.505451]  [<79677b1b>] kernel_init+0xb/0xe0
[    0.505451]  [<79075f42>] ? schedule_tail+0x12/0x40
[    0.505451]  [<79686580>] ret_from_kernel_thread+0x20/0x30
[    0.505451]  [<79677b10>] ? rest_init+0xc0/0xc0
[    0.505451] Code: 89 d8 e8 cf 9b 9f ff 8b 4f 04 8d 55 e4 89 d8 e8 72 9d 9f ff 8d 43 2c 89 c1 89 45 d8 8b 43 30 8d 55 e4 89 53 30 89 4d e4 89 45 e8 <89> 10 8b 55 dc 8b 45 e0 89 7d ec e8 db af 9f ff eb 11 90 31 c0
[    0.505451] EIP: [<79682de5>] mutex_lock_nested+0x135/0x2a0 SS:ESP 0068:78025e54
[    0.505451] CR2: 0000000000200200
[    0.505451] ---[ end trace ad8ac403ff8aef5e ]---
[    0.505451] Kernel panic - not syncing: Fatal exception

Fixes: 9ea9277 ("mac80211_hwsim: Register and bind to driver")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Junjie Mao <eternal.n08@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Userspace can add keys to an AP mode interface before start_ap has been
called. If there have been no calls to start_ap/stop_ap in the mean
time, the keys will still be around when the interface is brought down.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[adjust comments, fix AP_VLAN case]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If we are switching from an HT40+ to an HT40- channel (or vice-versa),
we need the secondary channel offset IE to specify what is the
post-CSA offset to be used.  This applies both to beacons and to probe
responses.

In ieee80211_parse_ch_switch_ie() we were ignoring this IE from
beacons and using the *current* HT information IE instead.  This was
causing us to use the same offset as before the switch.

Fix that by using the secondary channel offset IE also for beacons and
don't ever use the pre-switch offset.  Additionally, remove the
"beacon" argument from ieee80211_parse_ch_switch_ie(), since it's not
needed anymore.

Cc: stable@vger.kernel.org
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Due to the time it takes to process the beacon that started the CSA
process, we may be late for the switch if we try to reach exactly
beacon 0.  To avoid that, use count - 1 when calculating the switch time.

Cc: stable@vger.kernel.org
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The wireless hotkey of Dell Vostro 3546 does not work with Win8 OSI. Due
to insufficient documentation for the driver implementation, blacklist
it as a workaround.

Signed-off-by: Adam Lee <adam.lee@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When an interface is deleted, an ongoing hardware scan is canceled and
the driver must abort the scan, at the very least reporting completion
while the interface is removed.

However, if it scheduled the work that might only run after everything
is said and done, which leads to cfg80211 warning that the scan isn't
reported as finished yet; this is no fault of the driver, it already
did, but mac80211 hasn't processed it.

To fix this situation, flush the delayed work when the interface being
removed is the one that was executing the scan.

Cc: stable@vger.kernel.org
Reported-by: Sujith Manoharan <sujith@msujith.org>
Tested-by: Sujith Manoharan <sujith@msujith.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Priority of a merged request is computed by ioprio_best(). If one of the
requests has undefined priority (IOPRIO_CLASS_NONE) and another request
has priority from IOPRIO_CLASS_BE, the function will return the
undefined priority which is wrong. Fix the function to properly return
priority of a request with the defined priority.

Fixes: d58cdfb
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Reported-by: Meelis Roos <mroos@linux.ee>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
we are allocating memory using kzalloc for struct mvpp2_prs_entry,
but later when we are getting error we were just returning the error
value without releasing the memory.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should not be allocating a single byte of DMA coherent memory, but
instead a full-sized struct dma_desc (8 bytes).

Fixes: 80105be ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Callers of bcm_sysport_init_tx_ring() can currently fail, and will
always call bcm_sysport_fini_tx_ring() in a loop ending at the number of
TX queues (32) without checking if the TX ring was successfully
initialized or not.

Update bcm_sysport_fini_tx_ring() to return early and avoid a crash
de-referencing ring->cbs if the TX ring was not initialized, since
ring->cbs is the last part of the initialization done by
bcm_sysport_init_tx_ring() that could fail.

Fixes: 80105be ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver")
Reported-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:

====================
net: systemport: TX dma fixes

This patch series contains two fixes for our transmit path, first one
is a pretty nasty one since we were not allocating a large enough
dma coherent pool for our transmit descriptors, which would work most of the
time, since allocations are contiguous and we could have.

Second patch fixes a less frequent, though highly likley crash when using
CMA allocations.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
…x, xps-ethernetlite-2.00.b' for QEMU using

When use current latest upstream qemu (current version: 2.1.2), need let
driver compatible with 'xlnx,xps-ethernetlite-2.00.b', or can not find
net device in microblaze qemu. Related QEMU commands under fedora 20:

  yum install libvirt
  yum install tunctl
  tunctl -b
  ip link set tap0 up
  brctl addif virbr0 tap0
  ./microblaze-softmmu/qemu-system-microblaze -M petalogix-s3adsp1800 \
    -kernel ../linux-stable.microblaze/arch/microblaze/boot/linux.bin \
    -no-reboot -append "console=ttyUL0,115200 doreboot" -nographic \
    -net nic,vlan=0,model=xlnx.xps-ethernetlite,macaddr=00:16:35:AF:94:00 \
    -net tap,vlan=0,ifname=tap0,script=no,downscript=no

  in microblaze qemu bash (guest machine):

    ifconfig eth0 add 192.168.122.2 netmask 255.255.255.0
    ifconfig eth0 up

After add this patch, can find the device, and can be used by 'telnetd'
(need cross-build busybox with glibc for it), then outside can telnet to
it without password.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SMC91x is written to explicitly look up the IRQ resource
from the platform device and extract the IRQ and flags, however
the platform_get_irq() does additional things, like call
of_irq_get() in the device tree case, which will translate
the IRQ using the irqdomain and defer the probe if the
IRQ host cannot be found.

As we're not looking up the resource, this will not retrieve
the IRQ flags, but that is better done using
irqd_get_trigger_type(), as the trigger is what the driver
wants to modify. We take care to preserve the semantics that
will make the trigger type provided from the resource
override any local specifier.

Tested on the Nomadik NHK15 which has its SMC91x IRQ line
connected to a STMPE2401 GPIO expander on I2C.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Yet another device that needs this quirk.

Reported-by: Tanguy de Baritault <tdebaritault@gmail.com>
Signed-off-by: Adel Gadllah <adel.gadllah@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Upon receiving the last fragment, all but the first fragment
are freed, but the multicast check for statistics at the end
of the function refers to the current skb (the last fragment)
causing a use-after-free bug.

Since multicast frames cannot be fragmented and we check for
this early in the function, just modify that check to also
do the accounting to fix the issue.

Cc: stable@vger.kernel.org
Reported-by: Yosef Khyal <yosefx.khyal@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If the RFkill interrupt fires while we calibrate, it would
make the firmware fail and the driver wasn't able to recover.
Change the flow so that the driver will kill the firmware
in that case.

Since we have now two flows that are calling
trans_stop_device (the RFkill interrupt and the
op_mode_mvm_start function) - we need to better sync this.
Use the STATUS_DEVICE_ENABLED in the pcie transport in an
atomic way to achieve this.

This fixes: https://bugzilla.kernel.org/show_bug.cgi?id=86231

CC: <stable@vger.kernel.org> [3.10+]
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Fix:
net/bridge/netfilter/nft_reject_bridge.c:
In function 'nft_reject_br_send_v6_unreach':
net/bridge/netfilter/nft_reject_bridge.c:240:3:
	error: implicit declaration of function 'csum_ipv6_magic'
   csum_ipv6_magic(&nip6h->saddr, &nip6h->daddr,
   ^
make[3]: *** [net/bridge/netfilter/nft_reject_bridge.o] Error 1

Seen with powerpc:allmodconfig.

Fixes: 523b929 ("netfilter: nft_reject_bridge: don't use IP stack to reject traffic")
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The makefile for sanitizing kernel headers uses the kbuild file
to determine which files to do. Several networking related headers
were missing. Without these headers iproute2 build would break.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When VLAN acceleration is in use on the xmit path, we end up
setting csum_start to the wrong place.  The result is that the
whoever ends up doing the checksum setting will corrupt the packet
instead of writing the checksum to the expected location, usually
this means writing the checksum with an offset of -4.

This patch fixes this by adjusting csum_start when VLAN acceleration
is detected.

Fixes: 6680ec6 ("tuntap: hardware vlan tx support")
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We set the flag TUN_PKT_STRIP if the user buffer provided is too
small to contain the entire packet plus meta-data.  However, this
has been broken ever since we added GSO meta-data.  VLAN acceleration
also has the same problem.

This patch fixes this by taking both into account when setting the
TUN_PKT_STRIP flag.

The fact that this has been broken for six years without anyone
realising means that nobody actually uses this flag.

Fixes: f43798c ("tun: Allow GSO using virtio_net_hdr")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Herbert Xu says:

====================
tun: Fix csum_start and TUN_PKT_STRIP

The first patch fixes a serious problem that breaks checksum offload
in VMs while the second patch fixes a problem that probably affects
no one.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
On i.MX6SX sdb platform, there has two same enet MACs, after system up,
just eth0 is up, and then do suspend/resume test:

[   50.437967] PM: Syncing filesystems ... done.
[   50.476924] Freezing user space processes ... (elapsed 0.005 seconds) done.
[   50.490093] Freezing remaining freezable tasks ... (elapsed 0.004 seconds) done.
[   50.559771] ------------[ cut here ]------------
[   50.564453] WARNING: CPU: 0 PID: 575 at drivers/clk/clk.c:851 __clk_disable+0x60/0x6c()
[   50.572475] Modules linked in:
[   50.575578] CPU: 0 PID: 575 Comm: sh Not tainted 3.18.0-rc2-next-20141031-00007-gf61135b #21
[   50.584031] Backtrace:
[   50.586550] [<80011ecc>] (dump_backtrace) from [<8001206c>] (show_stack+0x18/0x1c)
[   50.594136]  r6:808a7a54 r5:00000000 r4:00000000 r3:00000000
[   50.599920] [<80012054>] (show_stack) from [<806ab3c0>] (dump_stack+0x80/0x9c)
[   50.607187] [<806ab340>] (dump_stack) from [<8002a3e8>] (warn_slowpath_common+0x6c/0x8c)
[   50.615294]  r5:00000353 r4:00000000
[   50.618940] [<8002a37c>] (warn_slowpath_common) from [<8002a42c>] (warn_slowpath_null+0x24/0x2c)
[   50.627738]  r8:00000000 r7:be144c44 r6:be015600 r5:80070013 r4:be015600
[   50.634573] [<8002a408>] (warn_slowpath_null) from [<804f8d4c>] (__clk_disable+0x60/0x6c)
[   50.642777] [<804f8cec>] (__clk_disable) from [<804f8e5c>] (clk_disable+0x2c/0x38)
[   50.650359]  r4:be015600 r3:00000000
[   50.654006] [<804f8e30>] (clk_disable) from [<80420ab4>] (fec_enet_clk_enable+0xc4/0x258)
[   50.662196]  r5:be3cb620 r4:be3cb000
[   50.665838] [<804209f0>] (fec_enet_clk_enable) from [<80421178>] (fec_suspend+0x30/0x180)
[   50.674026]  r7:be144c44 r6:be144c10 r5:8037f5a4 r4:be3cb000
[   50.679802] [<80421148>] (fec_suspend) from [<8037f5d8>] (platform_pm_suspend+0x34/0x64)
[   50.687906]  r10:00000000 r9:00000000 r8:00000000 r7:be144c44 r6:be144c10 r5:8037f5a4
[   50.695852]  r4:be144c10 r3:80421148
[   50.699511] [<8037f5a4>] (platform_pm_suspend) from [<8038784c>] (dpm_run_callback.isra.14+0x34/0x6c)
[   50.708764] [<80387818>] (dpm_run_callback.isra.14) from [<80387f00>] (__device_suspend+0x12c/0x2a4)
[   50.717909]  r9:8098ec8c r8:80973bec r6:00000002 r5:811c7038 r4:be144c10
[   50.724746] [<80387dd4>] (__device_suspend) from [<803894fc>] (dpm_suspend+0x64/0x224)
[   50.732675]  r8:80973bec r7:be144c10 r6:8098ec24 r5:811c7038 r4:be144cc4
[   50.739509] [<80389498>] (dpm_suspend) from [<8038999c>] (dpm_suspend_start+0x60/0x68)
[   50.747438]  r10:8082fa24 r9:00000000 r8:00000004 r7:00000003 r6:00000000 r5:8116ec80
[   50.755386]  r4:00000002
[   50.757969] [<8038993c>] (dpm_suspend_start) from [<800679d8>] (suspend_devices_and_enter+0x90/0x3ec)
[   50.767202]  r4:00000003 r3:8116eca0
[   50.770843] [<80067948>] (suspend_devices_and_enter) from [<80067f40>] (pm_suspend+0x20c/0x2a4)
[   50.779553]  r8:00000004 r7:00000003 r6:00000000 r5:8116ec8c r4:00000003
[   50.786394] [<80067d34>] (pm_suspend) from [<80066858>] (state_store+0x70/0xc0)
[   50.793718]  r6:8116ec90 r5:00000003 r4:bd88a800 r3:0000006d
[   50.799496] [<800667e8>] (state_store) from [<802b0384>] (kobj_attr_store+0x1c/0x28)
[   50.807251]  r10:bd399f78 r8:00000000 r7:bd88a800 r6:bd88a800 r5:00000004 r4:bd085680
[   50.815219] [<802b0368>] (kobj_attr_store) from [<80153090>] (sysfs_kf_write+0x54/0x58)
[   50.823252] [<8015303c>] (sysfs_kf_write) from [<80151fd8>] (kernfs_fop_write+0xd0/0x194)
[   50.831441]  r6:00000004 r5:bd08568c r4:bd085680 r3:8015303c
[   50.837220] [<80151f08>] (kernfs_fop_write) from [<800eddb4>] (vfs_write+0xb8/0x1a8)
[   50.844975]  r10:00000000 r9:00000000 r8:00000000 r7:bd399f78 r6:01336408 r5:00000004
[   50.852924]  r4:bc584dc0
[   50.855505] [<800edcfc>] (vfs_write) from [<800ee0b8>] (SyS_write+0x48/0x88)
[   50.862567]  r10:00000000 r8:00000000 r7:01336408 r6:00000004 r5:bc584dc0 r4:bc584dc0
[   50.870537] [<800ee070>] (SyS_write) from [<8000eb00>] (ret_fast_syscall+0x0/0x48)
[   50.878120]  r9:bd398000 r8:8000ecc4 r7:00000004 r6:76f42b48 r5:01336408 r4:00000004
[   50.885983] ---[ end trace 7545115d752a316a ]---
[   50.890765] ------------[ cut here ]------------

The root cause is that eth1 is not opened and clock is not enabled, and .suspend() still
call .fec_enet_clk_enable() to disable clock.

To avoid the broken, let it check network device up status by calling .netif_running()
before disable/enable clocks.

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dabrace pushed a commit that referenced this pull request Jun 30, 2020
Commit 7e9f5e6 ("arm64: vdso: Add --eh-frame-hdr to ldflags") results
in a .eh_frame_hdr section for the vDSO, which in turn causes the libgcc
unwinder to unwind out of signal handlers using the .eh_frame information
populated by our .cfi directives. In conjunction with a4eb355
("arm64: vdso: Fix CFI directives in sigreturn trampoline"), this has
been shown to cause segmentation faults originating from within the
unwinder during thread cancellation:

 | Thread 14 "virtio-net-rx" received signal SIGSEGV, Segmentation fault.
 | 0x0000000000435e24 in uw_frame_state_for ()
 | (gdb) bt
 | #0  0x0000000000435e24 in uw_frame_state_for ()
 | #1  0x0000000000436e88 in _Unwind_ForcedUnwind_Phase2 ()
 | #2  0x00000000004374d8 in _Unwind_ForcedUnwind ()
 | #3  0x0000000000428400 in __pthread_unwind (buf=<optimized out>) at unwind.c:121
 | #4  0x0000000000429808 in __do_cancel () at ./pthreadP.h:304
 | #5  sigcancel_handler (sig=32, si=0xffff33c743f0, ctx=<optimized out>) at nptl-init.c:200
 | #6  sigcancel_handler (sig=<optimized out>, si=0xffff33c743f0, ctx=<optimized out>) at nptl-init.c:165
 | #7  <signal handler called>
 | #8  futex_wait_cancelable (private=0, expected=0, futex_word=0x3890b708) at ../sysdeps/unix/sysv/linux/futex-internal.h:88

After considerable bashing of heads, it appears that our CFI directives
for unwinding out of the sigreturn trampoline are only processed by libgcc
when both a .eh_frame_hdr section is present *and* the mysterious NOP is
covered by an entry in .eh_frame. With both of these now in place, it has
highlighted that our CFI directives are not comprehensive enough to
restore the stack pointer of the interrupted context. This results in libgcc
falling back to an arm64-specific unwinder after computing a bogus PC value
from the unwind tables. The unwinder promptly dereferences this bogus address
in an attempt to see if the pointed-to instruction sequence looks like
the sigreturn trampoline.

Restore the old unwind behaviour, which relied solely on heuristics in
the unwinder, by removing the .eh_frame_hdr section from the vDSO and
commenting out the insufficient CFI directives for now. Add comments to
explain the current, miserable state of affairs.

Cc: Tamas Zsoldos <tamas.zsoldos@arm.com>
Cc: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Kiss <daniel.kiss@arm.com>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
dabrace pushed a commit that referenced this pull request Aug 14, 2020
This patch is to fix a crash:

 #3 [ffffb6580689f898] oops_end at ffffffffa2835bc2
 #4 [ffffb6580689f8b8] no_context at ffffffffa28766e7
 #5 [ffffb6580689f920] async_page_fault at ffffffffa320135e
    [exception RIP: f2fs_is_compressed_page+34]
    RIP: ffffffffa2ba83a2  RSP: ffffb6580689f9d8  RFLAGS: 00010213
    RAX: 0000000000000001  RBX: fffffc0f50b34bc0  RCX: 0000000000002122
    RDX: 0000000000002123  RSI: 0000000000000c00  RDI: fffffc0f50b34bc0
    RBP: ffff97e815a40178   R8: 0000000000000000   R9: ffff97e83ffc9000
    R10: 0000000000032300  R11: 0000000000032380  R12: ffffb6580689fa38
    R13: fffffc0f50b34bc0  R14: ffff97e825cbd000  R15: 0000000000000c00
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffffb6580689f9d8] __is_cp_guaranteed at ffffffffa2b7ea98
 #7 [ffffb6580689f9f0] f2fs_submit_page_write at ffffffffa2b81a69
 #8 [ffffb6580689fa30] f2fs_do_write_meta_page at ffffffffa2b99777
 #9 [ffffb6580689fae0] __f2fs_write_meta_page at ffffffffa2b75f1a
 #10 [ffffb6580689fb18] f2fs_sync_meta_pages at ffffffffa2b77466
 #11 [ffffb6580689fc98] do_checkpoint at ffffffffa2b78e46
 #12 [ffffb6580689fd88] f2fs_write_checkpoint at ffffffffa2b79c29
 #13 [ffffb6580689fdd0] f2fs_sync_fs at ffffffffa2b69d95
 #14 [ffffb6580689fe20] sync_filesystem at ffffffffa2ad2574
 #15 [ffffb6580689fe30] generic_shutdown_super at ffffffffa2a9b582
 #16 [ffffb6580689fe48] kill_block_super at ffffffffa2a9b6d1
 #17 [ffffb6580689fe60] kill_f2fs_super at ffffffffa2b6abe1
 #18 [ffffb6580689fea0] deactivate_locked_super at ffffffffa2a9afb6
 #19 [ffffb6580689feb8] cleanup_mnt at ffffffffa2abcad4
 #20 [ffffb6580689fee0] task_work_run at ffffffffa28bca28
 #21 [ffffb6580689ff00] exit_to_usermode_loop at ffffffffa28050b7
 #22 [ffffb6580689ff38] do_syscall_64 at ffffffffa280560e
 #23 [ffffb6580689ff50] entry_SYSCALL_64_after_hwframe at ffffffffa320008c

This occurred when umount f2fs if enable F2FS_FS_COMPRESSION
with F2FS_IO_TRACE. Fixes it by adding IS_IO_TRACED_PAGE to check
validity of pid for page_private.

Signed-off-by: Yu Changchun <yuchangchun1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
dabrace pushed a commit that referenced this pull request Aug 14, 2020
https://bugzilla.kernel.org/show_bug.cgi?id=208565

PID: 257    TASK: ecdd0000  CPU: 0   COMMAND: "init"
  #0 [<c0b420ec>] (__schedule) from [<c0b423c8>]
  #1 [<c0b423c8>] (schedule) from [<c0b459d4>]
  #2 [<c0b459d4>] (rwsem_down_read_failed) from [<c0b44fa0>]
  #3 [<c0b44fa0>] (down_read) from [<c044233c>]
  #4 [<c044233c>] (f2fs_truncate_blocks) from [<c0442890>]
  #5 [<c0442890>] (f2fs_truncate) from [<c044d408>]
  #6 [<c044d408>] (f2fs_evict_inode) from [<c030be18>]
  #7 [<c030be18>] (evict) from [<c030a558>]
  #8 [<c030a558>] (iput) from [<c047c600>]
  #9 [<c047c600>] (f2fs_sync_node_pages) from [<c0465414>]
 #10 [<c0465414>] (f2fs_write_checkpoint) from [<c04575f4>]
 #11 [<c04575f4>] (f2fs_sync_fs) from [<c0441918>]
 #12 [<c0441918>] (f2fs_do_sync_file) from [<c0441098>]
 #13 [<c0441098>] (f2fs_sync_file) from [<c0323fa0>]
 #14 [<c0323fa0>] (vfs_fsync_range) from [<c0324294>]
 #15 [<c0324294>] (do_fsync) from [<c0324014>]
 #16 [<c0324014>] (sys_fsync) from [<c0108bc0>]

This can be caused by flush_dirty_inode() in f2fs_sync_node_pages() where
iput() requires f2fs_lock_op() again resulting in livelock.

Reported-by: Zhiguo Niu <Zhiguo.Niu@unisoc.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
dabrace pushed a commit that referenced this pull request Sep 2, 2020
I got the following lockdep splat while testing:

  ======================================================
  WARNING: possible circular locking dependency detected
  5.8.0-rc7-00172-g021118712e59 torvalds#932 Not tainted
  ------------------------------------------------------
  btrfs/229626 is trying to acquire lock:
  ffffffff828513f0 (cpu_hotplug_lock){++++}-{0:0}, at: alloc_workqueue+0x378/0x450

  but task is already holding lock:
  ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #7 (&fs_info->scrub_lock){+.+.}-{3:3}:
	 __mutex_lock+0x9f/0x930
	 btrfs_scrub_dev+0x11c/0x630
	 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4
	 btrfs_ioctl+0x2799/0x30a0
	 ksys_ioctl+0x83/0xc0
	 __x64_sys_ioctl+0x16/0x20
	 do_syscall_64+0x50/0x90
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #6 (&fs_devs->device_list_mutex){+.+.}-{3:3}:
	 __mutex_lock+0x9f/0x930
	 btrfs_run_dev_stats+0x49/0x480
	 commit_cowonly_roots+0xb5/0x2a0
	 btrfs_commit_transaction+0x516/0xa60
	 sync_filesystem+0x6b/0x90
	 generic_shutdown_super+0x22/0x100
	 kill_anon_super+0xe/0x30
	 btrfs_kill_super+0x12/0x20
	 deactivate_locked_super+0x29/0x60
	 cleanup_mnt+0xb8/0x140
	 task_work_run+0x6d/0xb0
	 __prepare_exit_to_usermode+0x1cc/0x1e0
	 do_syscall_64+0x5c/0x90
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #5 (&fs_info->tree_log_mutex){+.+.}-{3:3}:
	 __mutex_lock+0x9f/0x930
	 btrfs_commit_transaction+0x4bb/0xa60
	 sync_filesystem+0x6b/0x90
	 generic_shutdown_super+0x22/0x100
	 kill_anon_super+0xe/0x30
	 btrfs_kill_super+0x12/0x20
	 deactivate_locked_super+0x29/0x60
	 cleanup_mnt+0xb8/0x140
	 task_work_run+0x6d/0xb0
	 __prepare_exit_to_usermode+0x1cc/0x1e0
	 do_syscall_64+0x5c/0x90
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #4 (&fs_info->reloc_mutex){+.+.}-{3:3}:
	 __mutex_lock+0x9f/0x930
	 btrfs_record_root_in_trans+0x43/0x70
	 start_transaction+0xd1/0x5d0
	 btrfs_dirty_inode+0x42/0xd0
	 touch_atime+0xa1/0xd0
	 btrfs_file_mmap+0x3f/0x60
	 mmap_region+0x3a4/0x640
	 do_mmap+0x376/0x580
	 vm_mmap_pgoff+0xd5/0x120
	 ksys_mmap_pgoff+0x193/0x230
	 do_syscall_64+0x50/0x90
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #3 (&mm->mmap_lock#2){++++}-{3:3}:
	 __might_fault+0x68/0x90
	 _copy_to_user+0x1e/0x80
	 perf_read+0x141/0x2c0
	 vfs_read+0xad/0x1b0
	 ksys_read+0x5f/0xe0
	 do_syscall_64+0x50/0x90
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  -> #2 (&cpuctx_mutex){+.+.}-{3:3}:
	 __mutex_lock+0x9f/0x930
	 perf_event_init_cpu+0x88/0x150
	 perf_event_init+0x1db/0x20b
	 start_kernel+0x3ae/0x53c
	 secondary_startup_64+0xa4/0xb0

  -> #1 (pmus_lock){+.+.}-{3:3}:
	 __mutex_lock+0x9f/0x930
	 perf_event_init_cpu+0x4f/0x150
	 cpuhp_invoke_callback+0xb1/0x900
	 _cpu_up.constprop.26+0x9f/0x130
	 cpu_up+0x7b/0xc0
	 bringup_nonboot_cpus+0x4f/0x60
	 smp_init+0x26/0x71
	 kernel_init_freeable+0x110/0x258
	 kernel_init+0xa/0x103
	 ret_from_fork+0x1f/0x30

  -> #0 (cpu_hotplug_lock){++++}-{0:0}:
	 __lock_acquire+0x1272/0x2310
	 lock_acquire+0x9e/0x360
	 cpus_read_lock+0x39/0xb0
	 alloc_workqueue+0x378/0x450
	 __btrfs_alloc_workqueue+0x15d/0x200
	 btrfs_alloc_workqueue+0x51/0x160
	 scrub_workers_get+0x5a/0x170
	 btrfs_scrub_dev+0x18c/0x630
	 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4
	 btrfs_ioctl+0x2799/0x30a0
	 ksys_ioctl+0x83/0xc0
	 __x64_sys_ioctl+0x16/0x20
	 do_syscall_64+0x50/0x90
	 entry_SYSCALL_64_after_hwframe+0x44/0xa9

  other info that might help us debug this:

  Chain exists of:
    cpu_hotplug_lock --> &fs_devs->device_list_mutex --> &fs_info->scrub_lock

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(&fs_info->scrub_lock);
				 lock(&fs_devs->device_list_mutex);
				 lock(&fs_info->scrub_lock);
    lock(cpu_hotplug_lock);

   *** DEADLOCK ***

  2 locks held by btrfs/229626:
   #0: ffff88bfe8bb86e0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: btrfs_scrub_dev+0xbd/0x630
   #1: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630

  stack backtrace:
  CPU: 15 PID: 229626 Comm: btrfs Kdump: loaded Not tainted 5.8.0-rc7-00172-g021118712e59 torvalds#932
  Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018
  Call Trace:
   dump_stack+0x78/0xa0
   check_noncircular+0x165/0x180
   __lock_acquire+0x1272/0x2310
   lock_acquire+0x9e/0x360
   ? alloc_workqueue+0x378/0x450
   cpus_read_lock+0x39/0xb0
   ? alloc_workqueue+0x378/0x450
   alloc_workqueue+0x378/0x450
   ? rcu_read_lock_sched_held+0x52/0x80
   __btrfs_alloc_workqueue+0x15d/0x200
   btrfs_alloc_workqueue+0x51/0x160
   scrub_workers_get+0x5a/0x170
   btrfs_scrub_dev+0x18c/0x630
   ? start_transaction+0xd1/0x5d0
   btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4
   btrfs_ioctl+0x2799/0x30a0
   ? do_sigaction+0x102/0x250
   ? lockdep_hardirqs_on_prepare+0xca/0x160
   ? _raw_spin_unlock_irq+0x24/0x30
   ? trace_hardirqs_on+0x1c/0xe0
   ? _raw_spin_unlock_irq+0x24/0x30
   ? do_sigaction+0x102/0x250
   ? ksys_ioctl+0x83/0xc0
   ksys_ioctl+0x83/0xc0
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x50/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

This happens because we're allocating the scrub workqueues under the
scrub and device list mutex, which brings in a whole host of other
dependencies.

Because the work queue allocation is done with GFP_KERNEL, it can
trigger reclaim, which can lead to a transaction commit, which in turns
needs the device_list_mutex, it can lead to a deadlock. A different
problem for which this fix is a solution.

Fix this by moving the actual allocation outside of the
scrub lock, and then only take the lock once we're ready to actually
assign them to the fs_info.  We'll now have to cleanup the workqueues in
a few more places, so I've added a helper to do the refcount dance to
safely free the workqueues.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
dabrace pushed a commit that referenced this pull request Sep 2, 2020
…s metrics" test

Linux 5.9 introduced perf test case "Parse and process metrics" and
on s390 this test case always dumps core:

  [root@t35lp67 perf]# ./perf test -vvvv -F 67
  67: Parse and process metrics                             :
  --- start ---
  metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC
  parsing metric: inst_retired.any / cpu_clk_unhalted.thread
  Segmentation fault (core dumped)
  [root@t35lp67 perf]#

I debugged this core dump and gdb shows this call chain:

  (gdb) where
   #0  0x000003ffabc3192a in __strnlen_c_1 () from /lib64/libc.so.6
   #1  0x000003ffabc293de in strcasestr () from /lib64/libc.so.6
   #2  0x0000000001102ba2 in match_metric(list=0x1e6ea20 "inst_retired.any",
            n=<optimized out>)
       at util/metricgroup.c:368
   #3  find_metric (map=<optimized out>, map=<optimized out>,
           metric=0x1e6ea20 "inst_retired.any")
      at util/metricgroup.c:765
   #4  __resolve_metric (ids=0x0, map=<optimized out>, metric_list=0x0,
           metric_no_group=<optimized out>, m=<optimized out>)
      at util/metricgroup.c:844
   #5  resolve_metric (ids=0x0, map=0x0, metric_list=0x0,
          metric_no_group=<optimized out>)
      at util/metricgroup.c:881
   #6  metricgroup__add_metric (metric=<optimized out>,
        metric_no_group=metric_no_group@entry=false, events=<optimized out>,
        events@entry=0x3ffd84fb878, metric_list=0x0,
        metric_list@entry=0x3ffd84fb868, map=0x0)
      at util/metricgroup.c:943
   #7  0x00000000011034ae in metricgroup__add_metric_list (map=0x13f9828 <map>,
        metric_list=0x3ffd84fb868, events=0x3ffd84fb878,
        metric_no_group=<optimized out>, list=<optimized out>)
      at util/metricgroup.c:988
   #8  parse_groups (perf_evlist=perf_evlist@entry=0x1e70260,
          str=str@entry=0x12f34b2 "IPC", metric_no_group=<optimized out>,
          metric_no_merge=<optimized out>,
          fake_pmu=fake_pmu@entry=0x1462f18 <perf_pmu.fake>,
          metric_events=0x3ffd84fba58, map=0x1)
      at util/metricgroup.c:1040
   #9  0x0000000001103eb2 in metricgroup__parse_groups_test(
  	evlist=evlist@entry=0x1e70260, map=map@entry=0x13f9828 <map>,
  	str=str@entry=0x12f34b2 "IPC",
  	metric_no_group=metric_no_group@entry=false,
  	metric_no_merge=metric_no_merge@entry=false,
  	metric_events=0x3ffd84fba58)
      at util/metricgroup.c:1082
   #10 0x00000000010c84d8 in __compute_metric (ratio2=0x0, name2=0x0,
          ratio1=<synthetic pointer>, name1=0x12f34b2 "IPC",
  	vals=0x3ffd84fbad8, name=0x12f34b2 "IPC")
      at tests/parse-metric.c:159
   #11 compute_metric (ratio=<synthetic pointer>, vals=0x3ffd84fbad8,
  	name=0x12f34b2 "IPC")
      at tests/parse-metric.c:189
   #12 test_ipc () at tests/parse-metric.c:208
.....
..... omitted many more lines

This test case was added with
commit 218ca91 ("perf tests: Add parse metric test for frontend metric").

When I compile with make DEBUG=y it works fine and I do not get a core dump.

It turned out that the above listed function call chain worked on a struct
pmu_event array which requires a trailing element with zeroes which was
missing. The marco map_for_each_event() loops over that array tests for members
metric_expr/metric_name/metric_group being non-NULL. Adding this element fixes
the issue.

Output after:

  [root@t35lp46 perf]# ./perf test 67
  67: Parse and process metrics                             : Ok
  [root@t35lp46 perf]#

Committer notes:

As Ian remarks, this is not s390 specific:

<quote Ian>
  This also shows up with address sanitizer on all architectures
  (perhaps change the patch title) and perhaps add a "Fixes: <commit>"
  tag.

  =================================================================
  ==4718==ERROR: AddressSanitizer: global-buffer-overflow on address
  0x55c93b4d59e8 at pc 0x55c93a1541e2 bp 0x7ffd24327c60 sp
  0x7ffd24327c58
  READ of size 8 at 0x55c93b4d59e8 thread T0
      #0 0x55c93a1541e1 in find_metric tools/perf/util/metricgroup.c:764:2
      #1 0x55c93a153e6c in __resolve_metric tools/perf/util/metricgroup.c:844:9
      #2 0x55c93a152f18 in resolve_metric tools/perf/util/metricgroup.c:881:9
      #3 0x55c93a1528db in metricgroup__add_metric
  tools/perf/util/metricgroup.c:943:9
      #4 0x55c93a151996 in metricgroup__add_metric_list
  tools/perf/util/metricgroup.c:988:9
      #5 0x55c93a1511b9 in parse_groups tools/perf/util/metricgroup.c:1040:8
      #6 0x55c93a1513e1 in metricgroup__parse_groups_test
  tools/perf/util/metricgroup.c:1082:9
      #7 0x55c93a0108ae in __compute_metric tools/perf/tests/parse-metric.c:159:8
      #8 0x55c93a010744 in compute_metric tools/perf/tests/parse-metric.c:189:9
      #9 0x55c93a00f5ee in test_ipc tools/perf/tests/parse-metric.c:208:2
      #10 0x55c93a00f1e8 in test__parse_metric
  tools/perf/tests/parse-metric.c:345:2
      #11 0x55c939fd7202 in run_test tools/perf/tests/builtin-test.c:410:9
      #12 0x55c939fd6736 in test_and_print tools/perf/tests/builtin-test.c:440:9
      #13 0x55c939fd58c3 in __cmd_test tools/perf/tests/builtin-test.c:661:4
      #14 0x55c939fd4e02 in cmd_test tools/perf/tests/builtin-test.c:807:9
      #15 0x55c939e4763d in run_builtin tools/perf/perf.c:313:11
      #16 0x55c939e46475 in handle_internal_command tools/perf/perf.c:365:8
      #17 0x55c939e4737e in run_argv tools/perf/perf.c:409:2
      #18 0x55c939e45f7e in main tools/perf/perf.c:539:3

  0x55c93b4d59e8 is located 0 bytes to the right of global variable
  'pme_test' defined in 'tools/perf/tests/parse-metric.c:17:25'
  (0x55c93b4d54a0) of size 1352
  SUMMARY: AddressSanitizer: global-buffer-overflow
  tools/perf/util/metricgroup.c:764:2 in find_metric
  Shadow bytes around the buggy address:
    0x0ab9a7692ae0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692af0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  =>0x0ab9a7692b30: 00 00 00 00 00 00 00 00 00 00 00 00 00[f9]f9 f9
    0x0ab9a7692b40: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
    0x0ab9a7692b50: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
    0x0ab9a7692b60: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 00 00 00 00
    0x0ab9a7692b70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ab9a7692b80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
  Shadow byte legend (one shadow byte represents 8 application bytes):
    Addressable:           00
    Partially addressable: 01 02 03 04 05 06 07
    Heap left redzone:	   fa
    Freed heap region:	   fd
    Stack left redzone:	   f1
    Stack mid redzone:	   f2
    Stack right redzone:     f3
    Stack after return:	   f5
    Stack use after scope:   f8
    Global redzone:          f9
    Global init order:	   f6
    Poisoned by user:        f7
    Container overflow:	   fc
    Array cookie:            ac
    Intra object redzone:    bb
    ASan internal:           fe
    Left alloca redzone:     ca
    Right alloca redzone:    cb
    Shadow gap:              cc
</quote>

I'm also adding the missing "Fixes" tag and setting just .name to NULL,
as doing it that way is more compact (the compiler will zero out
everything else) and the table iterators look for .name being NULL as
the sentinel marking the end of the table.

Fixes: 0a507af ("perf tests: Add parse metric test for ipc metric")
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200825071211.16959-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Sep 17, 2020
The aliases were never released causing the following leaks:

  Indirect leak of 1224 byte(s) in 9 object(s) allocated from:
    #0 0x7feefb830628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
    #1 0x56332c8f1b62 in __perf_pmu__new_alias util/pmu.c:322
    #2 0x56332c8f401f in pmu_add_cpu_aliases_map util/pmu.c:778
    #3 0x56332c792ce9 in __test__pmu_event_aliases tests/pmu-events.c:295
    #4 0x56332c792ce9 in test_aliases tests/pmu-events.c:367
    #5 0x56332c76a09b in run_test tests/builtin-test.c:410
    #6 0x56332c76a09b in test_and_print tests/builtin-test.c:440
    #7 0x56332c76ce69 in __cmd_test tests/builtin-test.c:695
    #8 0x56332c76ce69 in cmd_test tests/builtin-test.c:807
    #9 0x56332c7d2214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #10 0x56332c6701a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #11 0x56332c6701a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #12 0x56332c6701a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #13 0x7feefb359cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: 956a783 ("perf test: Test pmu-events aliases")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-11-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Sep 17, 2020
The evsel->unit borrows a pointer of pmu event or alias instead of
owns a string.  But tool event (duration_time) passes a result of
strdup() caused a leak.

It was found by ASAN during metric test:

  Direct leak of 210 byte(s) in 70 object(s) allocated from:
    #0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
    #1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414
    #2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414
    #3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
    #4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
    #5 0x559fbbcc95da in __parse_events util/parse-events.c:2141
    #6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406
    #7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393
    #8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415
    #9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498
    #10 0x559fbbc0109b in run_test tests/builtin-test.c:410
    #11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
    #12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
    #13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
    #14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: f0fbb11 ("perf stat: Implement duration_time as a proper event")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Sep 17, 2020
The test_generic_metric() missed to release entries in the pctx.  Asan
reported following leak (and more):

  Direct leak of 128 byte(s) in 1 object(s) allocated from:
    #0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
    #1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14)
    #2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497)
    #3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111
    #4 0x55f7e7341667 in expr__add_ref util/expr.c:120
    #5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783
    #6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858
    #7 0x55f7e712390b in compute_single tests/parse-metric.c:128
    #8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180
    #9 0x55f7e712446d in compute_metric tests/parse-metric.c:196
    #10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295
    #11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355
    #12 0x55f7e70be09b in run_test tests/builtin-test.c:410
    #13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
    #14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
    #15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
    #16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: 6d432c4 ("perf tools: Add test_generic_metric function")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Sep 17, 2020
The metricgroup__add_metric() can find multiple match for a metric group
and it's possible to fail.  Also it can fail in the middle like in
resolve_metric() even for single metric.

In those cases, the intermediate list and ids will be leaked like:

  Direct leak of 3 byte(s) in 1 object(s) allocated from:
    #0 0x7f4c938f40b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
    #1 0x55f7e71c1bef in __add_metric util/metricgroup.c:683
    #2 0x55f7e71c31d0 in add_metric util/metricgroup.c:906
    #3 0x55f7e71c3844 in metricgroup__add_metric util/metricgroup.c:940
    #4 0x55f7e71c488d in metricgroup__add_metric_list util/metricgroup.c:993
    #5 0x55f7e71c488d in parse_groups util/metricgroup.c:1045
    #6 0x55f7e71c60a4 in metricgroup__parse_groups_test util/metricgroup.c:1087
    #7 0x55f7e71235ae in __compute_metric tests/parse-metric.c:164
    #8 0x55f7e7124650 in compute_metric tests/parse-metric.c:196
    #9 0x55f7e7124650 in test_recursion_fail tests/parse-metric.c:318
    #10 0x55f7e7124650 in test__parse_metric tests/parse-metric.c:356
    #11 0x55f7e70be09b in run_test tests/builtin-test.c:410
    #12 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
    #13 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
    #14 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
    #15 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #16 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #17 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #18 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #19 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: 83de0b7 ("perf metric: Collect referenced metrics in struct metric_ref_node")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Sep 17, 2020
The following leaks were detected by ASAN:

  Indirect leak of 360 byte(s) in 9 object(s) allocated from:
    #0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
    #1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333
    #2 0x560578f752fc in perf_pmu_parse util/pmu.y:59
    #3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73
    #4 0x560578e07045 in test__pmu tests/pmu.c:155
    #5 0x560578de109b in run_test tests/builtin-test.c:410
    #6 0x560578de109b in test_and_print tests/builtin-test.c:440
    #7 0x560578de401a in __cmd_test tests/builtin-test.c:661
    #8 0x560578de401a in cmd_test tests/builtin-test.c:807
    #9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
    #10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
    #11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
    #12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
    #13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308

Fixes: cff7f95 ("perf tests: Move pmu tests into separate object")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Sep 21, 2020
Commit

  b972fdb ("EDAC/ghes: Fix NULL pointer dereference in ghes_edac_register()")

didn't clear all the information from the scanned system and, more
specifically, left ghes_hw.num_dimms to its previous value. On a
second load (CONFIG_DEBUG_TEST_DRIVER_REMOVE=y), the driver would use
the leftover num_dimms value which is not 0 and thus the 0 check in
enumerate_dimms() will get bypassed and it would go directly to the
pointer deref:

  d = &hw->dimms[hw->num_dimms];

which is, of course, NULL:

  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD 0 P4D 0
  Oops: 0002 [#1] PREEMPT SMP
  CPU: 7 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc4+ #7
  Hardware name: GIGABYTE MZ01-CE1-00/MZ01-CE1-00, BIOS F02 08/29/2018
  RIP: 0010:enumerate_dimms.cold+0x7b/0x375

Reset the whole ghes_hw on driver unregister so that no stale values are
used on a second system scan.

Fixes: b972fdb ("EDAC/ghes: Fix NULL pointer dereference in ghes_edac_register()")
Cc: Shiju Jose <shiju.jose@huawei.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200911164817.GA19320@zn.tnic
dabrace pushed a commit that referenced this pull request Nov 5, 2020
Very sporadically I had test case btrfs/069 from fstests hanging (for
years, it is not a recent regression), with the following traces in
dmesg/syslog:

  [162301.160628] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg started
  [162301.181196] BTRFS info (device sdc): scrub: finished on devid 4 with status: 0
  [162301.287162] BTRFS info (device sdc): dev_replace from /dev/sdd (devid 2) to /dev/sdg finished
  [162513.513792] INFO: task btrfs-transacti:1356167 blocked for more than 120 seconds.
  [162513.514318]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.514522] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.514747] task:btrfs-transacti state:D stack:    0 pid:1356167 ppid:     2 flags:0x00004000
  [162513.514751] Call Trace:
  [162513.514761]  __schedule+0x5ce/0xd00
  [162513.514765]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.514771]  schedule+0x46/0xf0
  [162513.514844]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.514850]  ? finish_wait+0x90/0x90
  [162513.514864]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.514879]  transaction_kthread+0xa4/0x170 [btrfs]
  [162513.514891]  ? btrfs_cleanup_transaction+0x660/0x660 [btrfs]
  [162513.514894]  kthread+0x153/0x170
  [162513.514897]  ? kthread_stop+0x2c0/0x2c0
  [162513.514902]  ret_from_fork+0x22/0x30
  [162513.514916] INFO: task fsstress:1356184 blocked for more than 120 seconds.
  [162513.515192]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.515431] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.515680] task:fsstress        state:D stack:    0 pid:1356184 ppid:1356177 flags:0x00004000
  [162513.515682] Call Trace:
  [162513.515688]  __schedule+0x5ce/0xd00
  [162513.515691]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.515697]  schedule+0x46/0xf0
  [162513.515712]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.515716]  ? finish_wait+0x90/0x90
  [162513.515729]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.515743]  btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
  [162513.515753]  btrfs_sync_fs+0x61/0x1c0 [btrfs]
  [162513.515758]  ? __ia32_sys_fdatasync+0x20/0x20
  [162513.515761]  iterate_supers+0x87/0xf0
  [162513.515765]  ksys_sync+0x60/0xb0
  [162513.515768]  __do_sys_sync+0xa/0x10
  [162513.515771]  do_syscall_64+0x33/0x80
  [162513.515774]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.515781] RIP: 0033:0x7f5238f50bd7
  [162513.515782] Code: Bad RIP value.
  [162513.515784] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
  [162513.515786] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
  [162513.515788] RDX: 00000000ffffffff RSI: 000000000daf0e74 RDI: 000000000000003a
  [162513.515789] RBP: 0000000000000032 R08: 000000000000000a R09: 00007f5239019be0
  [162513.515791] R10: fffffffffffff24f R11: 0000000000000206 R12: 000000000000003a
  [162513.515792] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
  [162513.515804] INFO: task fsstress:1356185 blocked for more than 120 seconds.
  [162513.516064]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.516329] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.516617] task:fsstress        state:D stack:    0 pid:1356185 ppid:1356177 flags:0x00000000
  [162513.516620] Call Trace:
  [162513.516625]  __schedule+0x5ce/0xd00
  [162513.516628]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.516634]  schedule+0x46/0xf0
  [162513.516647]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.516650]  ? finish_wait+0x90/0x90
  [162513.516662]  start_transaction+0x4d7/0x5f0 [btrfs]
  [162513.516679]  btrfs_setxattr_trans+0x3c/0x100 [btrfs]
  [162513.516686]  __vfs_setxattr+0x66/0x80
  [162513.516691]  __vfs_setxattr_noperm+0x70/0x200
  [162513.516697]  vfs_setxattr+0x6b/0x120
  [162513.516703]  setxattr+0x125/0x240
  [162513.516709]  ? lock_acquire+0xb1/0x480
  [162513.516712]  ? mnt_want_write+0x20/0x50
  [162513.516721]  ? rcu_read_lock_any_held+0x8e/0xb0
  [162513.516723]  ? preempt_count_add+0x49/0xa0
  [162513.516725]  ? __sb_start_write+0x19b/0x290
  [162513.516727]  ? preempt_count_add+0x49/0xa0
  [162513.516732]  path_setxattr+0xba/0xd0
  [162513.516739]  __x64_sys_setxattr+0x27/0x30
  [162513.516741]  do_syscall_64+0x33/0x80
  [162513.516743]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.516745] RIP: 0033:0x7f5238f56d5a
  [162513.516746] Code: Bad RIP value.
  [162513.516748] RSP: 002b:00007fff67b97868 EFLAGS: 00000202 ORIG_RAX: 00000000000000bc
  [162513.516750] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f5238f56d5a
  [162513.516751] RDX: 000055b1fbb0d5a0 RSI: 00007fff67b978a0 RDI: 000055b1fbb0d470
  [162513.516753] RBP: 000055b1fbb0d5a0 R08: 0000000000000001 R09: 00007fff67b97700
  [162513.516754] R10: 0000000000000004 R11: 0000000000000202 R12: 0000000000000004
  [162513.516756] R13: 0000000000000024 R14: 0000000000000001 R15: 00007fff67b978a0
  [162513.516767] INFO: task fsstress:1356196 blocked for more than 120 seconds.
  [162513.517064]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.517365] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.517763] task:fsstress        state:D stack:    0 pid:1356196 ppid:1356177 flags:0x00004000
  [162513.517780] Call Trace:
  [162513.517786]  __schedule+0x5ce/0xd00
  [162513.517789]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.517796]  schedule+0x46/0xf0
  [162513.517810]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.517814]  ? finish_wait+0x90/0x90
  [162513.517829]  start_transaction+0x37c/0x5f0 [btrfs]
  [162513.517845]  btrfs_attach_transaction_barrier+0x1f/0x50 [btrfs]
  [162513.517857]  btrfs_sync_fs+0x61/0x1c0 [btrfs]
  [162513.517862]  ? __ia32_sys_fdatasync+0x20/0x20
  [162513.517865]  iterate_supers+0x87/0xf0
  [162513.517869]  ksys_sync+0x60/0xb0
  [162513.517872]  __do_sys_sync+0xa/0x10
  [162513.517875]  do_syscall_64+0x33/0x80
  [162513.517878]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.517881] RIP: 0033:0x7f5238f50bd7
  [162513.517883] Code: Bad RIP value.
  [162513.517885] RSP: 002b:00007fff67b978e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a2
  [162513.517887] RAX: ffffffffffffffda RBX: 000055b1fad2c560 RCX: 00007f5238f50bd7
  [162513.517889] RDX: 0000000000000000 RSI: 000000007660add2 RDI: 0000000000000053
  [162513.517891] RBP: 0000000000000032 R08: 0000000000000067 R09: 00007f5239019be0
  [162513.517893] R10: fffffffffffff24f R11: 0000000000000206 R12: 0000000000000053
  [162513.517895] R13: 00007fff67b97950 R14: 00007fff67b97906 R15: 000055b1fad1a340
  [162513.517908] INFO: task fsstress:1356197 blocked for more than 120 seconds.
  [162513.518298]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.518672] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.519157] task:fsstress        state:D stack:    0 pid:1356197 ppid:1356177 flags:0x00000000
  [162513.519160] Call Trace:
  [162513.519165]  __schedule+0x5ce/0xd00
  [162513.519168]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.519174]  schedule+0x46/0xf0
  [162513.519190]  wait_current_trans+0xde/0x140 [btrfs]
  [162513.519193]  ? finish_wait+0x90/0x90
  [162513.519206]  start_transaction+0x4d7/0x5f0 [btrfs]
  [162513.519222]  btrfs_create+0x57/0x200 [btrfs]
  [162513.519230]  lookup_open+0x522/0x650
  [162513.519246]  path_openat+0x2b8/0xa50
  [162513.519270]  do_filp_open+0x91/0x100
  [162513.519275]  ? find_held_lock+0x32/0x90
  [162513.519280]  ? lock_acquired+0x33b/0x470
  [162513.519285]  ? do_raw_spin_unlock+0x4b/0xc0
  [162513.519287]  ? _raw_spin_unlock+0x29/0x40
  [162513.519295]  do_sys_openat2+0x20d/0x2d0
  [162513.519300]  do_sys_open+0x44/0x80
  [162513.519304]  do_syscall_64+0x33/0x80
  [162513.519307]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.519309] RIP: 0033:0x7f5238f4a903
  [162513.519310] Code: Bad RIP value.
  [162513.519312] RSP: 002b:00007fff67b97758 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
  [162513.519314] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f5238f4a903
  [162513.519316] RDX: 0000000000000000 RSI: 00000000000001b6 RDI: 000055b1fbb0d470
  [162513.519317] RBP: 00007fff67b978c0 R08: 0000000000000001 R09: 0000000000000002
  [162513.519319] R10: 00007fff67b974f7 R11: 0000000000000246 R12: 0000000000000013
  [162513.519320] R13: 00000000000001b6 R14: 00007fff67b97906 R15: 000055b1fad1c620
  [162513.519332] INFO: task btrfs:1356211 blocked for more than 120 seconds.
  [162513.519727]       Not tainted 5.9.0-rc6-btrfs-next-69 #1
  [162513.520115] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [162513.520508] task:btrfs           state:D stack:    0 pid:1356211 ppid:1356178 flags:0x00004002
  [162513.520511] Call Trace:
  [162513.520516]  __schedule+0x5ce/0xd00
  [162513.520519]  ? _raw_spin_unlock_irqrestore+0x3c/0x60
  [162513.520525]  schedule+0x46/0xf0
  [162513.520544]  btrfs_scrub_pause+0x11f/0x180 [btrfs]
  [162513.520548]  ? finish_wait+0x90/0x90
  [162513.520562]  btrfs_commit_transaction+0x45a/0xc30 [btrfs]
  [162513.520574]  ? start_transaction+0xe0/0x5f0 [btrfs]
  [162513.520596]  btrfs_dev_replace_finishing+0x6d8/0x711 [btrfs]
  [162513.520619]  btrfs_dev_replace_by_ioctl.cold+0x1cc/0x1fd [btrfs]
  [162513.520639]  btrfs_ioctl+0x2a25/0x36f0 [btrfs]
  [162513.520643]  ? do_sigaction+0xf3/0x240
  [162513.520645]  ? find_held_lock+0x32/0x90
  [162513.520648]  ? do_sigaction+0xf3/0x240
  [162513.520651]  ? lock_acquired+0x33b/0x470
  [162513.520655]  ? _raw_spin_unlock_irq+0x24/0x50
  [162513.520657]  ? lockdep_hardirqs_on+0x7d/0x100
  [162513.520660]  ? _raw_spin_unlock_irq+0x35/0x50
  [162513.520662]  ? do_sigaction+0xf3/0x240
  [162513.520671]  ? __x64_sys_ioctl+0x83/0xb0
  [162513.520672]  __x64_sys_ioctl+0x83/0xb0
  [162513.520677]  do_syscall_64+0x33/0x80
  [162513.520679]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  [162513.520681] RIP: 0033:0x7fc3cd307d87
  [162513.520682] Code: Bad RIP value.
  [162513.520684] RSP: 002b:00007ffe30a56bb8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
  [162513.520686] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007fc3cd307d87
  [162513.520687] RDX: 00007ffe30a57a30 RSI: 00000000ca289435 RDI: 0000000000000003
  [162513.520689] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  [162513.520690] R10: 0000000000000008 R11: 0000000000000202 R12: 0000000000000003
  [162513.520692] R13: 0000557323a212e0 R14: 00007ffe30a5a520 R15: 0000000000000001
  [162513.520703]
		  Showing all locks held in the system:
  [162513.520712] 1 lock held by khungtaskd/54:
  [162513.520713]  #0: ffffffffb40a91a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x197
  [162513.520728] 1 lock held by in:imklog/596:
  [162513.520729]  #0: ffff8f3f0d781400 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x4d/0x60
  [162513.520782] 1 lock held by btrfs-transacti/1356167:
  [162513.520784]  #0: ffff8f3d810cc848 (&fs_info->transaction_kthread_mutex){+.+.}-{3:3}, at: transaction_kthread+0x4a/0x170 [btrfs]
  [162513.520798] 1 lock held by btrfs/1356190:
  [162513.520800]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x22/0x60
  [162513.520805] 1 lock held by fsstress/1356184:
  [162513.520806]  #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
  [162513.520811] 3 locks held by fsstress/1356185:
  [162513.520812]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
  [162513.520815]  #1: ffff8f3d80a650b8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: vfs_setxattr+0x50/0x120
  [162513.520820]  #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
  [162513.520833] 1 lock held by fsstress/1356196:
  [162513.520834]  #0: ffff8f3d576440e8 (&type->s_umount_key#62){++++}-{3:3}, at: iterate_supers+0x6f/0xf0
  [162513.520838] 3 locks held by fsstress/1356197:
  [162513.520839]  #0: ffff8f3d57644470 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x20/0x50
  [162513.520843]  #1: ffff8f3d506465e8 (&type->i_mutex_dir_key#10){++++}-{3:3}, at: path_openat+0x2a7/0xa50
  [162513.520846]  #2: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]
  [162513.520858] 2 locks held by btrfs/1356211:
  [162513.520859]  #0: ffff8f3d810cde30 (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+.}-{3:3}, at: btrfs_dev_replace_finishing+0x52/0x711 [btrfs]
  [162513.520877]  #1: ffff8f3d57644690 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40e/0x5f0 [btrfs]

This was weird because the stack traces show that a transaction commit,
triggered by a device replace operation, is blocking trying to pause any
running scrubs but there are no stack traces of blocked tasks doing a
scrub.

After poking around with drgn, I noticed there was a scrub task that was
constantly running and blocking for shorts periods of time:

  >>> t = find_task(prog, 1356190)
  >>> prog.stack_trace(t)
  #0  __schedule+0x5ce/0xcfc
  #1  schedule+0x46/0xe4
  #2  schedule_timeout+0x1df/0x475
  #3  btrfs_reada_wait+0xda/0x132
  #4  scrub_stripe+0x2a8/0x112f
  #5  scrub_chunk+0xcd/0x134
  #6  scrub_enumerate_chunks+0x29e/0x5ee
  #7  btrfs_scrub_dev+0x2d5/0x91b
  #8  btrfs_ioctl+0x7f5/0x36e7
  #9  __x64_sys_ioctl+0x83/0xb0
  #10 do_syscall_64+0x33/0x77
  #11 entry_SYSCALL_64+0x7c/0x156

Which corresponds to:

int btrfs_reada_wait(void *handle)
{
    struct reada_control *rc = handle;
    struct btrfs_fs_info *fs_info = rc->fs_info;

    while (atomic_read(&rc->elems)) {
        if (!atomic_read(&fs_info->reada_works_cnt))
            reada_start_machine(fs_info);
        wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
                          (HZ + 9) / 10);
    }
(...)

So the counter "rc->elems" was set to 1 and never decreased to 0, causing
the scrub task to loop forever in that function. Then I used the following
script for drgn to check the readahead requests:

  $ cat dump_reada.py
  import sys
  import drgn
  from drgn import NULL, Object, cast, container_of, execscript, \
      reinterpret, sizeof
  from drgn.helpers.linux import *

  mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"

  mnt = None
  for mnt in for_each_mount(prog, dst = mnt_path):
      pass

  if mnt is None:
      sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
      sys.exit(1)

  fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)

  def dump_re(re):
      nzones = re.nzones.value_()
      print(f're at {hex(re.value_())}')
      print(f'\t logical {re.logical.value_()}')
      print(f'\t refcnt {re.refcnt.value_()}')
      print(f'\t nzones {nzones}')
      for i in range(nzones):
          dev = re.zones[i].device
          name = dev.name.str.string_()
          print(f'\t\t dev id {dev.devid.value_()} name {name}')
      print()

  for _, e in radix_tree_for_each(fs_info.reada_tree):
      re = cast('struct reada_extent *', e)
      dump_re(re)

  $ drgn dump_reada.py
  re at 0xffff8f3da9d25ad8
          logical 38928384
          refcnt 1
          nzones 1
                 dev id 0 name b'/dev/sdd'
  $

So there was one readahead extent with a single zone corresponding to the
source device of that last device replace operation logged in dmesg/syslog.
Also the ID of that zone's device was 0 which is a special value set in
the source device of a device replace operation when the operation finishes
(constant BTRFS_DEV_REPLACE_DEVID set at btrfs_dev_replace_finishing()),
confirming again that device /dev/sdd was the source of a device replace
operation.

Normally there should be as many zones in the readahead extent as there are
devices, and I wasn't expecting the extent to be in a block group with a
'single' profile, so I went and confirmed with the following drgn script
that there weren't any single profile block groups:

  $ cat dump_block_groups.py
  import sys
  import drgn
  from drgn import NULL, Object, cast, container_of, execscript, \
      reinterpret, sizeof
  from drgn.helpers.linux import *

  mnt_path = b"/home/fdmanana/btrfs-tests/scratch_1"

  mnt = None
  for mnt in for_each_mount(prog, dst = mnt_path):
      pass

  if mnt is None:
      sys.stderr.write(f'Error: mount point {mnt_path} not found\n')
      sys.exit(1)

  fs_info = cast('struct btrfs_fs_info *', mnt.mnt.mnt_sb.s_fs_info)

  BTRFS_BLOCK_GROUP_DATA = (1 << 0)
  BTRFS_BLOCK_GROUP_SYSTEM = (1 << 1)
  BTRFS_BLOCK_GROUP_METADATA = (1 << 2)
  BTRFS_BLOCK_GROUP_RAID0 = (1 << 3)
  BTRFS_BLOCK_GROUP_RAID1 = (1 << 4)
  BTRFS_BLOCK_GROUP_DUP = (1 << 5)
  BTRFS_BLOCK_GROUP_RAID10 = (1 << 6)
  BTRFS_BLOCK_GROUP_RAID5 = (1 << 7)
  BTRFS_BLOCK_GROUP_RAID6 = (1 << 8)
  BTRFS_BLOCK_GROUP_RAID1C3 = (1 << 9)
  BTRFS_BLOCK_GROUP_RAID1C4 = (1 << 10)

  def bg_flags_string(bg):
      flags = bg.flags.value_()
      ret = ''
      if flags & BTRFS_BLOCK_GROUP_DATA:
          ret = 'data'
      if flags & BTRFS_BLOCK_GROUP_METADATA:
          if len(ret) > 0:
              ret += '|'
          ret += 'meta'
      if flags & BTRFS_BLOCK_GROUP_SYSTEM:
          if len(ret) > 0:
              ret += '|'
          ret += 'system'
      if flags & BTRFS_BLOCK_GROUP_RAID0:
          ret += ' raid0'
      elif flags & BTRFS_BLOCK_GROUP_RAID1:
          ret += ' raid1'
      elif flags & BTRFS_BLOCK_GROUP_DUP:
          ret += ' dup'
      elif flags & BTRFS_BLOCK_GROUP_RAID10:
          ret += ' raid10'
      elif flags & BTRFS_BLOCK_GROUP_RAID5:
          ret += ' raid5'
      elif flags & BTRFS_BLOCK_GROUP_RAID6:
          ret += ' raid6'
      elif flags & BTRFS_BLOCK_GROUP_RAID1C3:
          ret += ' raid1c3'
      elif flags & BTRFS_BLOCK_GROUP_RAID1C4:
          ret += ' raid1c4'
      else:
          ret += ' single'

      return ret

  def dump_bg(bg):
      print()
      print(f'block group at {hex(bg.value_())}')
      print(f'\t start {bg.start.value_()} length {bg.length.value_()}')
      print(f'\t flags {bg.flags.value_()} - {bg_flags_string(bg)}')

  bg_root = fs_info.block_group_cache_tree.address_of_()
  for bg in rbtree_inorder_for_each_entry('struct btrfs_block_group', bg_root, 'cache_node'):
      dump_bg(bg)

  $ drgn dump_block_groups.py

  block group at 0xffff8f3d673b0400
         start 22020096 length 16777216
         flags 258 - system raid6

  block group at 0xffff8f3d53ddb400
         start 38797312 length 536870912
         flags 260 - meta raid6

  block group at 0xffff8f3d5f4d9c00
         start 575668224 length 2147483648
         flags 257 - data raid6

  block group at 0xffff8f3d08189000
         start 2723151872 length 67108864
         flags 258 - system raid6

  block group at 0xffff8f3db70ff000
         start 2790260736 length 1073741824
         flags 260 - meta raid6

  block group at 0xffff8f3d5f4dd800
         start 3864002560 length 67108864
         flags 258 - system raid6

  block group at 0xffff8f3d67037000
         start 3931111424 length 2147483648
         flags 257 - data raid6
  $

So there were only 2 reasons left for having a readahead extent with a
single zone: reada_find_zone(), called when creating a readahead extent,
returned NULL either because we failed to find the corresponding block
group or because a memory allocation failed. With some additional and
custom tracing I figured out that on every further ocurrence of the
problem the block group had just been deleted when we were looping to
create the zones for the readahead extent (at reada_find_extent()), so we
ended up with only one zone in the readahead extent, corresponding to a
device that ends up getting replaced.

So after figuring that out it became obvious why the hang happens:

1) Task A starts a scrub on any device of the filesystem, except for
   device /dev/sdd;

2) Task B starts a device replace with /dev/sdd as the source device;

3) Task A calls btrfs_reada_add() from scrub_stripe() and it is currently
   starting to scrub a stripe from block group X. This call to
   btrfs_reada_add() is the one for the extent tree. When btrfs_reada_add()
   calls reada_add_block(), it passes the logical address of the extent
   tree's root node as its 'logical' argument - a value of 38928384;

4) Task A then enters reada_find_extent(), called from reada_add_block().
   It finds there isn't any existing readahead extent for the logical
   address 38928384, so it proceeds to the path of creating a new one.

   It calls btrfs_map_block() to find out which stripes exist for the block
   group X. On the first iteration of the for loop that iterates over the
   stripes, it finds the stripe for device /dev/sdd, so it creates one
   zone for that device and adds it to the readahead extent. Before getting
   into the second iteration of the loop, the cleanup kthread deletes block
   group X because it was empty. So in the iterations for the remaining
   stripes it does not add more zones to the readahead extent, because the
   calls to reada_find_zone() returned NULL because they couldn't find
   block group X anymore.

   As a result the new readahead extent has a single zone, corresponding to
   the device /dev/sdd;

4) Before task A returns to btrfs_reada_add() and queues the readahead job
   for the readahead work queue, task B finishes the device replace and at
   btrfs_dev_replace_finishing() swaps the device /dev/sdd with the new
   device /dev/sdg;

5) Task A returns to reada_add_block(), which increments the counter
   "->elems" of the reada_control structure allocated at btrfs_reada_add().

   Then it returns back to btrfs_reada_add() and calls
   reada_start_machine(). This queues a job in the readahead work queue to
   run the function reada_start_machine_worker(), which calls
   __reada_start_machine().

   At __reada_start_machine() we take the device list mutex and for each
   device found in the current device list, we call
   reada_start_machine_dev() to start the readahead work. However at this
   point the device /dev/sdd was already freed and is not in the device
   list anymore.

   This means the corresponding readahead for the extent at 38928384 is
   never started, and therefore the "->elems" counter of the reada_control
   structure allocated at btrfs_reada_add() never goes down to 0, causing
   the call to btrfs_reada_wait(), done by the scrub task, to wait forever.

Note that the readahead request can be made either after the device replace
started or before it started, however in pratice it is very unlikely that a
device replace is able to start after a readahead request is made and is
able to complete before the readahead request completes - maybe only on a
very small and nearly empty filesystem.

This hang however is not the only problem we can have with readahead and
device removals. When the readahead extent has other zones other than the
one corresponding to the device that is being removed (either by a device
replace or a device remove operation), we risk having a use-after-free on
the device when dropping the last reference of the readahead extent.

For example if we create a readahead extent with two zones, one for the
device /dev/sdd and one for the device /dev/sde:

1) Before the readahead worker starts, the device /dev/sdd is removed,
   and the corresponding btrfs_device structure is freed. However the
   readahead extent still has the zone pointing to the device structure;

2) When the readahead worker starts, it only finds device /dev/sde in the
   current device list of the filesystem;

3) It starts the readahead work, at reada_start_machine_dev(), using the
   device /dev/sde;

4) Then when it finishes reading the extent from device /dev/sde, it calls
   __readahead_hook() which ends up dropping the last reference on the
   readahead extent through the last call to reada_extent_put();

5) At reada_extent_put() it iterates over each zone of the readahead extent
   and attempts to delete an element from the device's 'reada_extents'
   radix tree, resulting in a use-after-free, as the device pointer of the
   zone for /dev/sdd is now stale. We can also access the device after
   dropping the last reference of a zone, through reada_zone_release(),
   also called by reada_extent_put().

And a device remove suffers the same problem, however since it shrinks the
device size down to zero before removing the device, it is very unlikely to
still have readahead requests not completed by the time we free the device,
the only possibility is if the device has a very little space allocated.

While the hang problem is exclusive to scrub, since it is currently the
only user of btrfs_reada_add() and btrfs_reada_wait(), the use-after-free
problem affects any path that triggers readhead, which includes
btree_readahead_hook() and __readahead_hook() (a readahead worker can
trigger readahed for the children of a node) for example - any path that
ends up calling reada_add_block() can trigger the use-after-free after a
device is removed.

So fix this by waiting for any readahead requests for a device to complete
before removing a device, ensuring that while waiting for existing ones no
new ones can be made.

This problem has been around for a very long time - the readahead code was
added in 2011, device remove exists since 2008 and device replace was
introduced in 2013, hard to pick a specific commit for a git Fixes tag.

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
dabrace pushed a commit that referenced this pull request Nov 23, 2020
This fix is for a failure that occurred in the DWARF unwind perf test.

Stack unwinders may probe memory when looking for frames.

Memory sanitizer will poison and track uninitialized memory on the
stack, and on the heap if the value is copied to the heap.

This can lead to false memory sanitizer failures for the use of an
uninitialized value.

Avoid this problem by removing the poison on the copied stack.

The full msan failure with track origins looks like:

==2168==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x559ceb10755b in handle_cfi elfutils/libdwfl/frame_unwind.c:648:8
    #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4
    #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7
    #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10
    #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17
    #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17
    #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14
    #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10
    #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8
    #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8
    #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26
    #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0)
    #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2
    #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9
    #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9
    #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8
    #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9
    #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9
    #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4
    #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9
    #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11
    #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8
    #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2
    #23 0x559cea95fbce in main tools/perf/perf.c:539:3

  Uninitialized value was stored to memory at
    #0 0x559ceb106acf in __libdwfl_frame_reg_set elfutils/libdwfl/frame_unwind.c:77:22
    #1 0x559ceb106acf in handle_cfi elfutils/libdwfl/frame_unwind.c:627:13
    #2 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4
    #3 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7
    #4 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10
    #5 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17
    #6 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17
    #7 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14
    #8 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10
    #9 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8
    #10 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8
    #11 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26
    #12 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0)
    #13 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2
    #14 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9
    #15 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9
    #16 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8
    #17 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9
    #18 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9
    #19 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4
    #20 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9
    #21 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11
    #22 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8
    #23 0x559cea95fbce in run_argv tools/perf/perf.c:409:2
    #24 0x559cea95fbce in main tools/perf/perf.c:539:3

  Uninitialized value was stored to memory at
    #0 0x559ceb106a54 in handle_cfi elfutils/libdwfl/frame_unwind.c:613:9
    #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4
    #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7
    #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10
    #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17
    #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17
    #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14
    #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10
    #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8
    #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8
    #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26
    #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0)
    #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2
    #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9
    #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9
    #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8
    #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9
    #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9
    #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4
    #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9
    #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11
    #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8
    #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2
    #23 0x559cea95fbce in main tools/perf/perf.c:539:3

  Uninitialized value was stored to memory at
    #0 0x559ceaff8800 in memory_read tools/perf/util/unwind-libdw.c:156:10
    #1 0x559ceb10f053 in expr_eval elfutils/libdwfl/frame_unwind.c:501:13
    #2 0x559ceb1060cc in handle_cfi elfutils/libdwfl/frame_unwind.c:603:18
    #3 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4
    #4 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7
    #5 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10
    #6 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17
    #7 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17
    #8 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14
    #9 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10
    #10 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8
    #11 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8
    #12 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26
    #13 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0)
    #14 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2
    #15 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9
    #16 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9
    #17 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8
    #18 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9
    #19 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9
    #20 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4
    #21 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9
    #22 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11
    #23 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8
    #24 0x559cea95fbce in run_argv tools/perf/perf.c:409:2
    #25 0x559cea95fbce in main tools/perf/perf.c:539:3

  Uninitialized value was stored to memory at
    #0 0x559cea9027d9 in __msan_memcpy llvm/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1558:3
    #1 0x559cea9d2185 in sample_ustack tools/perf/arch/x86/tests/dwarf-unwind.c:41:2
    #2 0x559cea9d202c in test__arch_unwind_sample tools/perf/arch/x86/tests/dwarf-unwind.c:72:9
    #3 0x559ceabc9cbd in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:106:6
    #4 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26
    #5 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0)
    #6 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2
    #7 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9
    #8 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9
    #9 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8
    #10 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9
    #11 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9
    #12 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4
    #13 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9
    #14 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11
    #15 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8
    #16 0x559cea95fbce in run_argv tools/perf/perf.c:409:2
    #17 0x559cea95fbce in main tools/perf/perf.c:539:3

  Uninitialized value was created by an allocation of 'bf' in the stack frame of function 'perf_event__synthesize_mmap_events'
    #0 0x559ceafc5f60 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:445

SUMMARY: MemorySanitizer: use-of-uninitialized-value elfutils/libdwfl/frame_unwind.c:648:8 in handle_cfi
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: clang-built-linux@googlegroups.com
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandeep Dasgupta <sdasgup@google.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201113182053.754625-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Nov 23, 2020
Actually, burst size is equal to '1 << desc->rqcfg.brst_size'.
we should use burst size, not desc->rqcfg.brst_size.

dma memcpy performance on Rockchip RV1126
@ 1512MHz A7, 1056MHz LPDDR3, 200MHz DMA:

dmatest:

/# echo dma0chan0 > /sys/module/dmatest/parameters/channel
/# echo 4194304 > /sys/module/dmatest/parameters/test_buf_size
/# echo 8 > /sys/module/dmatest/parameters/iterations
/# echo y > /sys/module/dmatest/parameters/norandom
/# echo y > /sys/module/dmatest/parameters/verbose
/# echo 1 > /sys/module/dmatest/parameters/run

dmatest: dma0chan0-copy0: result #1: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #2: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #3: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #4: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #5: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #6: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #7: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000
dmatest: dma0chan0-copy0: result #8: 'test passed' with src_off=0x0 dst_off=0x0 len=0x400000

Before:

  dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 48 iops 200338 KB/s (0)

After this patch:

  dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 179 iops 734873 KB/s (0)

After this patch and increase dma clk to 400MHz:

  dmatest: dma0chan0-copy0: summary 8 tests, 0 failures 259 iops 1062929 KB/s (0)

Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Link: https://lore.kernel.org/r/1605326106-55681-1-git-send-email-sugar.zhang@rock-chips.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
dabrace pushed a commit that referenced this pull request Jan 19, 2021
We had kernel panic, it is caused by unload module and last
close confirmation.

call trace:
[1196029.743127]  free_sess+0x15/0x50 [rtrs_client]
[1196029.743128]  rtrs_clt_close+0x4c/0x70 [rtrs_client]
[1196029.743129]  ? rnbd_clt_unmap_device+0x1b0/0x1b0 [rnbd_client]
[1196029.743130]  close_rtrs+0x25/0x50 [rnbd_client]
[1196029.743131]  rnbd_client_exit+0x93/0xb99 [rnbd_client]
[1196029.743132]  __x64_sys_delete_module+0x190/0x260

And in the crashdump confirmation kworker is also running.
PID: 6943   TASK: ffff9e2ac8098000  CPU: 4   COMMAND: "kworker/4:2"
 #0 [ffffb206cf337c30] __schedule at ffffffff9f93f891
 #1 [ffffb206cf337cc8] schedule at ffffffff9f93fe98
 #2 [ffffb206cf337cd0] schedule_timeout at ffffffff9f943938
 #3 [ffffb206cf337d50] wait_for_completion at ffffffff9f9410a7
 #4 [ffffb206cf337da0] __flush_work at ffffffff9f08ce0e
 #5 [ffffb206cf337e20] rtrs_clt_close_conns at ffffffffc0d5f668 [rtrs_client]
 #6 [ffffb206cf337e48] rtrs_clt_close at ffffffffc0d5f801 [rtrs_client]
 #7 [ffffb206cf337e68] close_rtrs at ffffffffc0d26255 [rnbd_client]
 #8 [ffffb206cf337e78] free_sess at ffffffffc0d262ad [rnbd_client]
 #9 [ffffb206cf337e88] rnbd_clt_put_dev at ffffffffc0d266a7 [rnbd_client]

The problem is both code path try to close same session, which lead to
panic.

To fix it, just skip the sess if the refcount already drop to 0.

Fixes: f7a7a5c ("block/rnbd: client: main functionality")
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
The evlist has the maps with its own refcounts so we don't need to set
the pointers to NULL.  Otherwise following error was reported by Asan.

  # perf test -v 4
   4: Read samples using the mmap interface      :
  --- start ---
  test child forked, pid 139782
  mmap size 528384B

  =================================================================
  ==139782==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7f1f76daee8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x564ba21a0fea in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x564ba21a1a0f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x564ba21a21cf in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x564ba21a21cf in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x564ba1e48298 in test__basic_mmap tests/mmap-basic.c:55
    #6 0x564ba1e278fb in run_test tests/builtin-test.c:428
    #7 0x564ba1e278fb in test_and_print tests/builtin-test.c:458
    #8 0x564ba1e29a53 in __cmd_test tests/builtin-test.c:679
    #9 0x564ba1e29a53 in cmd_test tests/builtin-test.c:825
    #10 0x564ba1e95cb4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #11 0x564ba1d1fa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #12 0x564ba1d1fa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #13 0x564ba1d1fa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #14 0x7f1f768e4d09 in __libc_start_main ../csu/libc-start.c:308

    ...
  test child finished with 1
  ---- end ----
  Read samples using the mmap interface: FAILED!
  failed to open shell test directory: /home/namhyung/libexec/perf-core/tests/shell

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20210301140409.184570-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
The evlist has the maps with its own refcounts so we don't need to set
the pointers to NULL.  Otherwise following error was reported by Asan.

Also change the goto label since it doesn't need to have two.

  # perf test -v 24
  24: Number of exit events of a simple workload :
  --- start ---
  test child forked, pid 145915
  mmap size 528384B

  =================================================================
  ==145915==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fc44e50d1f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164
    #1 0x561cf50f4d2e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23
    #2 0x561cf4eeb949 in thread_map__new_by_tid util/thread_map.c:63
    #3 0x561cf4db7fd2 in test__task_exit tests/task-exit.c:74
    #4 0x561cf4d798fb in run_test tests/builtin-test.c:428
    #5 0x561cf4d798fb in test_and_print tests/builtin-test.c:458
    #6 0x561cf4d7ba53 in __cmd_test tests/builtin-test.c:679
    #7 0x561cf4d7ba53 in cmd_test tests/builtin-test.c:825
    #8 0x561cf4de7d04 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #9 0x561cf4c71a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #10 0x561cf4c71a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #11 0x561cf4c71a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #12 0x7fc44e042d09 in __libc_start_main ../csu/libc-start.c:308

    ...
  test child finished with 1
  ---- end ----
  Number of exit events of a simple workload: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
The evlist has the maps with its own refcounts so we don't need to set
the pointers to NULL.  Otherwise following error was reported by Asan.

Also change the goto label since it doesn't need to have two.

  # perf test -v 25
  25: Software clock events period values        :
  --- start ---
  test child forked, pid 149154
  mmap size 528384B
  mmap size 528384B

  =================================================================
  ==149154==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fef5cd071f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164
    #1 0x56260d5e8b8e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23
    #2 0x56260d3df7a9 in thread_map__new_by_tid util/thread_map.c:63
    #3 0x56260d2ac6b2 in __test__sw_clock_freq tests/sw-clock.c:65
    #4 0x56260d26d8fb in run_test tests/builtin-test.c:428
    #5 0x56260d26d8fb in test_and_print tests/builtin-test.c:458
    #6 0x56260d26fa53 in __cmd_test tests/builtin-test.c:679
    #7 0x56260d26fa53 in cmd_test tests/builtin-test.c:825
    #8 0x56260d2dbb64 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #9 0x56260d165a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #10 0x56260d165a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #11 0x56260d165a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #12 0x7fef5c83cd09 in __libc_start_main ../csu/libc-start.c:308

    ...
  test child finished with 1
  ---- end ----
  Software clock events period values      : FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-5-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
The evlist and the cpu/thread maps should be released together.
Otherwise following error was reported by Asan.

Note that this test still has memory leaks in DSOs so it still fails
even after this change.  I'll take a look at that too.

  # perf test -v 26
  26: Object code reading                        :
  --- start ---
  test child forked, pid 154184
  Looking at the vmlinux_path (8 entries long)
  symsrc__init: build id mismatch for vmlinux.
  symsrc__init: cannot get elf header.
  Using /proc/kcore for kernel data
  Using /proc/kallsyms for symbols
  Parsing event 'cycles'
  mmap size 528384B
  ...
  =================================================================
  ==154184==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 439 byte(s) in 1 object(s) allocated from:
    #0 0x7fcb66e77037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x55ad9b7e821e in dso__new_id util/dso.c:1256
    #2 0x55ad9b8cfd4a in __machine__addnew_vdso util/vdso.c:132
    #3 0x55ad9b8cfd4a in machine__findnew_vdso util/vdso.c:347
    #4 0x55ad9b845b7e in map__new util/map.c:176
    #5 0x55ad9b8415a2 in machine__process_mmap2_event util/machine.c:1787
    #6 0x55ad9b8fab16 in perf_tool__process_synth_event util/synthetic-events.c:64
    #7 0x55ad9b8fab16 in perf_event__synthesize_mmap_events util/synthetic-events.c:499
    #8 0x55ad9b8fbfdf in __event__synthesize_thread util/synthetic-events.c:741
    #9 0x55ad9b8ff3e3 in perf_event__synthesize_thread_map util/synthetic-events.c:833
    #10 0x55ad9b738585 in do_test_code_reading tests/code-reading.c:608
    #11 0x55ad9b73b25d in test__code_reading tests/code-reading.c:722
    #12 0x55ad9b6f28fb in run_test tests/builtin-test.c:428
    #13 0x55ad9b6f28fb in test_and_print tests/builtin-test.c:458
    #14 0x55ad9b6f4a53 in __cmd_test tests/builtin-test.c:679
    #15 0x55ad9b6f4a53 in cmd_test tests/builtin-test.c:825
    #16 0x55ad9b760cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #17 0x55ad9b5eaa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #18 0x55ad9b5eaa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #19 0x55ad9b5eaa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #20 0x7fcb669acd09 in __libc_start_main ../csu/libc-start.c:308

    ...
  SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Object code reading: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
The evlist and the cpu/thread maps should be released together.
Otherwise following error was reported by Asan.

  $ perf test -v 28
  28: Use a dummy software event to keep tracking:
  --- start ---
  test child forked, pid 156810
  mmap size 528384B

  =================================================================
  ==156810==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7f637d2bce8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55cc6295cffa in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x55cc6295da1f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x55cc6295e1df in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x55cc6295e1df in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x55cc626287cf in test__keep_tracking tests/keep-tracking.c:84
    #6 0x55cc625e38fb in run_test tests/builtin-test.c:428
    #7 0x55cc625e38fb in test_and_print tests/builtin-test.c:458
    #8 0x55cc625e5a53 in __cmd_test tests/builtin-test.c:679
    #9 0x55cc625e5a53 in cmd_test tests/builtin-test.c:825
    #10 0x55cc62651cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #11 0x55cc624dba88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #12 0x55cc624dba88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #13 0x55cc624dba88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #14 0x7f637cdf2d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Use a dummy software event to keep tracking: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
The evlist and cpu/thread maps should be released together.
Otherwise the following error was reported by Asan.

  $ perf test -v 35
  35: Track with sched_switch                    :
  --- start ---
  test child forked, pid 159287
  Using CPUID GenuineIntel-6-8E-C
  mmap size 528384B
  1295 events recorded

  =================================================================
  ==159287==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7fa28d9a2e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x5652f5a5affa in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x5652f5a5ba1f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x5652f5a5c1df in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x5652f5a5c1df in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x5652f5723bbf in test__switch_tracking tests/switch-tracking.c:350
    #6 0x5652f56e18fb in run_test tests/builtin-test.c:428
    #7 0x5652f56e18fb in test_and_print tests/builtin-test.c:458
    #8 0x5652f56e3a53 in __cmd_test tests/builtin-test.c:679
    #9 0x5652f56e3a53 in cmd_test tests/builtin-test.c:825
    #10 0x5652f574fcc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #11 0x5652f55d9a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #12 0x5652f55d9a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #13 0x5652f55d9a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #14 0x7fa28d4d8d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Track with sched_switch: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
It missed to call perf_thread_map__put() after using the map.

  $ perf test -v 43
  43: Synthesize thread map                      :
  --- start ---
  test child forked, pid 162640

  =================================================================
  ==162640==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fd48cdaa1f8 in __interceptor_realloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:164
    #1 0x563e6d5f8d0e in perf_thread_map__realloc /home/namhyung/project/linux/tools/lib/perf/threadmap.c:23
    #2 0x563e6d3ef69a in thread_map__new_by_pid util/thread_map.c:46
    #3 0x563e6d2cec90 in test__thread_map_synthesize tests/thread-map.c:97
    #4 0x563e6d27d8fb in run_test tests/builtin-test.c:428
    #5 0x563e6d27d8fb in test_and_print tests/builtin-test.c:458
    #6 0x563e6d27fa53 in __cmd_test tests/builtin-test.c:679
    #7 0x563e6d27fa53 in cmd_test tests/builtin-test.c:825
    #8 0x563e6d2ebce4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #9 0x563e6d175a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #10 0x563e6d175a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #11 0x563e6d175a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #12 0x7fd48c8dfd09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 8224 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Synthesize thread map: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
It should be released after printing the map.

  $ perf test -v 52
  52: Print cpu map                              :
  --- start ---
  test child forked, pid 172233

  =================================================================
  ==172233==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 156 byte(s) in 1 object(s) allocated from:
    #0 0x7fc472518e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55e63b378f7a in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x55e63b37a05c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237
    #3 0x55e63b056d16 in cpu_map_print tests/cpumap.c:102
    #4 0x55e63b056d16 in test__cpu_map_print tests/cpumap.c:120
    #5 0x55e63afff8fb in run_test tests/builtin-test.c:428
    #6 0x55e63afff8fb in test_and_print tests/builtin-test.c:458
    #7 0x55e63b001a53 in __cmd_test tests/builtin-test.c:679
    #8 0x55e63b001a53 in cmd_test tests/builtin-test.c:825
    #9 0x55e63b06dc44 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #10 0x55e63aef7a88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #11 0x55e63aef7a88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #12 0x55e63aef7a88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #13 0x7fc47204ed09 in __libc_start_main ../csu/libc-start.c:308
  ...

  SUMMARY: AddressSanitizer: 448 byte(s) leaked in 7 allocation(s).
  test child finished with 1
  ---- end ----
  Print cpu map: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-11-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
It should release the maps at the end.

  $ perf test -v 71
  71: Convert perf time to TSC                   :
  --- start ---
  test child forked, pid 178744
  mmap size 528384B
  1st event perf time 59207256505278 tsc 13187166645142
  rdtsc          time 59207256542151 tsc 13187166723020
  2nd event perf time 59207256543749 tsc 13187166726393

  =================================================================
  ==178744==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x7faf601f9e8f in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
    #1 0x55b620cfc00a in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
    #2 0x55b620cfca2f in perf_cpu_map__read /home/namhyung/project/linux/tools/lib/perf/cpumap.c:149
    #3 0x55b620cfd1ef in cpu_map__read_all_cpu_map /home/namhyung/project/linux/tools/lib/perf/cpumap.c:166
    #4 0x55b620cfd1ef in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:181
    #5 0x55b6209ef1b2 in test__perf_time_to_tsc tests/perf-time-to-tsc.c:73
    #6 0x55b6209828fb in run_test tests/builtin-test.c:428
    #7 0x55b6209828fb in test_and_print tests/builtin-test.c:458
    #8 0x55b620984a53 in __cmd_test tests/builtin-test.c:679
    #9 0x55b620984a53 in cmd_test tests/builtin-test.c:825
    #10 0x55b6209f0cd4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #11 0x55b62087aa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #12 0x55b62087aa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #13 0x55b62087aa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #14 0x7faf5fd2fd09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 72 byte(s) leaked in 2 allocation(s).
  test child finished with 1
  ---- end ----
  Convert perf time to TSC: FAILED!

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210301140409.184570-12-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Mar 24, 2021
I got a segfault when using -r option with event groups.  The option
makes it run the workload multiple times and it will reuse the evlist
and evsel for each run.

While most of resources are allocated and freed properly, the id hash
in the evlist was not and it resulted in the bug.  You can see it with
the address sanitizer like below:

  $ perf stat -r 100 -e '{cycles,instructions}' true
  =================================================================
  ==693052==ERROR: AddressSanitizer: heap-use-after-free on
      address 0x6080000003d0 at pc 0x558c57732835 bp 0x7fff1526adb0 sp 0x7fff1526ada8
  WRITE of size 8 at 0x6080000003d0 thread T0
    #0 0x558c57732834 in hlist_add_head /home/namhyung/project/linux/tools/include/linux/list.h:644
    #1 0x558c57732834 in perf_evlist__id_hash /home/namhyung/project/linux/tools/lib/perf/evlist.c:237
    #2 0x558c57732834 in perf_evlist__id_add /home/namhyung/project/linux/tools/lib/perf/evlist.c:244
    #3 0x558c57732834 in perf_evlist__id_add_fd /home/namhyung/project/linux/tools/lib/perf/evlist.c:285
    #4 0x558c5747733e in store_evsel_ids util/evsel.c:2765
    #5 0x558c5747733e in evsel__store_ids util/evsel.c:2782
    #6 0x558c5730b717 in __run_perf_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:895
    #7 0x558c5730b717 in run_perf_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:1014
    #8 0x558c5730b717 in cmd_stat /home/namhyung/project/linux/tools/perf/builtin-stat.c:2446
    #9 0x558c57427c24 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #10 0x558c572b1a48 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #11 0x558c572b1a48 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #12 0x558c572b1a48 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #13 0x7fcadb9f7d09 in __libc_start_main ../csu/libc-start.c:308
    #14 0x558c572b60f9 in _start (/home/namhyung/project/linux/tools/perf/perf+0x45d0f9)

Actually the nodes in the hash table are struct perf_stream_id and
they were freed in the previous run.  Fix it by resetting the hash.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20210225035148.778569-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Apr 6, 2021
I got several memory leak reports from Asan with a simple command.  It
was because VDSO is not released due to the refcount.  Like in
__dsos_addnew_id(), it should put the refcount after adding to the list.

  $ perf record true
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ]

  =================================================================
  ==692599==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 439 byte(s) in 1 object(s) allocated from:
    #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256
    #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132
    #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347
    #4 0x559bce50826c in map__new util/map.c:175
    #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
    #6 0x559bce512f6b in machines__deliver_event util/session.c:1481
    #7 0x559bce515107 in perf_session__deliver_event util/session.c:1551
    #8 0x559bce51d4d2 in do_flush util/ordered-events.c:244
    #9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
    #10 0x559bce519bea in __perf_session__process_events util/session.c:2268
    #11 0x559bce519bea in perf_session__process_events util/session.c:2297
    #12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
    #13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
    #14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
    #15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
    #16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308

  Indirect leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
    #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169
    #2 0x559bce50821b in map__new util/map.c:168
    #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
    #4 0x559bce512f6b in machines__deliver_event util/session.c:1481
    #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551
    #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244
    #7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
    #8 0x559bce519bea in __perf_session__process_events util/session.c:2268
    #9 0x559bce519bea in perf_session__process_events util/session.c:2297
    #10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
    #11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
    #12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
    #13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
    #14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
    #15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
    #16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
    #17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
    #18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308

  SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210315045641.700430-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
dabrace pushed a commit that referenced this pull request Apr 16, 2021
It's possible for iwl_pcie_enqueue_hcmd() to be called with hard IRQs
disabled (e.g. from LED core). We can't enable BHs in such a situation.

Turn the unconditional BH-enable/BH-disable code into
hardirq-disable/conditional-enable.

This fixes the warning below.

 WARNING: CPU: 1 PID: 1139 at kernel/softirq.c:178 __local_bh_enable_ip+0xa5/0xf0
 CPU: 1 PID: 1139 Comm: NetworkManager Not tainted 5.12.0-rc1-00004-gb4ded168af79 #7
 Hardware name: LENOVO 20K5S22R00/20K5S22R00, BIOS R0IET38W (1.16 ) 05/31/2017
 RIP: 0010:__local_bh_enable_ip+0xa5/0xf0
 Code: f7 69 e8 ee 23 14 00 fb 66 0f 1f 44 00 00 65 8b 05 f0 f4 f7 69 85 c0 74 3f 48 83 c4 08 5b c3 65 8b 05 9b fe f7 69 85 c0 75 8e <0f> 0b eb 8a 48 89 3c 24 e8 4e 20 14 00 48 8b 3c 24 eb 91 e8 13 4e
 RSP: 0018:ffffafd580b13298 EFLAGS: 00010046
 RAX: 0000000000000000 RBX: 0000000000000201 RCX: 0000000000000000
 RDX: 0000000000000003 RSI: 0000000000000201 RDI: ffffffffc1272389
 RBP: ffff96517ae4c018 R08: 0000000000000001 R09: 0000000000000000
 R10: ffffafd580b13178 R11: 0000000000000001 R12: ffff96517b060000
 R13: 0000000000000000 R14: ffffffff80000000 R15: 0000000000000001
 FS:  00007fc604ebefc0(0000) GS:ffff965267480000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000055fb3fef13b2 CR3: 0000000109112004 CR4: 00000000003706e0
 Call Trace:
  ? _raw_spin_unlock_bh+0x1f/0x30
  iwl_pcie_enqueue_hcmd+0x5d9/0xa00 [iwlwifi]
  iwl_trans_txq_send_hcmd+0x6c/0x430 [iwlwifi]
  iwl_trans_send_cmd+0x88/0x170 [iwlwifi]
  ? lock_acquire+0x277/0x3d0
  iwl_mvm_send_cmd+0x32/0x80 [iwlmvm]
  iwl_mvm_led_set+0xc2/0xe0 [iwlmvm]
  ? led_trigger_event+0x46/0x70
  led_trigger_event+0x46/0x70
  ieee80211_do_open+0x5c5/0xa20 [mac80211]
  ieee80211_open+0x67/0x90 [mac80211]
  __dev_open+0xd4/0x150
  __dev_change_flags+0x19e/0x1f0
  dev_change_flags+0x23/0x60
  do_setlink+0x30d/0x1230
  ? lock_is_held_type+0xb4/0x120
  ? __nla_validate_parse.part.7+0x57/0xcb0
  ? __lock_acquire+0x2e1/0x1a50
  __rtnl_newlink+0x560/0x910
  ? __lock_acquire+0x2e1/0x1a50
  ? __lock_acquire+0x2e1/0x1a50
  ? lock_acquire+0x277/0x3d0
  ? sock_def_readable+0x5/0x290
  ? lock_is_held_type+0xb4/0x120
  ? find_held_lock+0x2d/0x90
  ? sock_def_readable+0xb3/0x290
  ? lock_release+0x166/0x2a0
  ? lock_is_held_type+0x90/0x120
  rtnl_newlink+0x47/0x70
  rtnetlink_rcv_msg+0x25c/0x470
  ? netlink_deliver_tap+0x97/0x3e0
  ? validate_linkmsg+0x350/0x350
  netlink_rcv_skb+0x50/0x100
  netlink_unicast+0x1b2/0x280
  netlink_sendmsg+0x336/0x450
  sock_sendmsg+0x5b/0x60
  ____sys_sendmsg+0x1ed/0x250
  ? copy_msghdr_from_user+0x5c/0x90
  ___sys_sendmsg+0x88/0xd0
  ? lock_is_held_type+0xb4/0x120
  ? find_held_lock+0x2d/0x90
  ? lock_release+0x166/0x2a0
  ? __fget_files+0xfe/0x1d0
  ? __sys_sendmsg+0x5e/0xa0
  __sys_sendmsg+0x5e/0xa0
  ? lockdep_hardirqs_on_prepare+0xd9/0x170
  do_syscall_64+0x33/0x80
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7fc605c9572d
 Code: 28 89 54 24 1c 48 89 74 24 10 89 7c 24 08 e8 da ee ff ff 8b 54 24 1c 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 33 44 89 c7 48 89 44 24 08 e8 2e ef ff ff 48
 RSP: 002b:00007fffc83789f0 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 000055ef468570c0 RCX: 00007fc605c9572d
 RDX: 0000000000000000 RSI: 00007fffc8378a30 RDI: 000000000000000c
 RBP: 0000000000000010 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
 R13: 00007fffc8378b80 R14: 00007fffc8378b7c R15: 0000000000000000
 irq event stamp: 170785
 hardirqs last  enabled at (170783): [<ffffffff9609a8c2>] __local_bh_enable_ip+0x82/0xf0
 hardirqs last disabled at (170784): [<ffffffff96a8613d>] _raw_read_lock_irqsave+0x8d/0x90
 softirqs last  enabled at (170782): [<ffffffffc1272389>] iwl_pcie_enqueue_hcmd+0x5d9/0xa00 [iwlwifi]
 softirqs last disabled at (170785): [<ffffffffc1271ec6>] iwl_pcie_enqueue_hcmd+0x116/0xa00 [iwlwifi]

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v12.0.0-rc3
Acked-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/nycvar.YFH.7.76.2103021125430.12405@cbobk.fhfr.pm
dabrace pushed a commit that referenced this pull request Apr 16, 2021
The following deadlock is detected:

  truncate -> setattr path is waiting for pending direct IO to be done (inode->i_dio_count become zero) with inode->i_rwsem held (down_write).

  PID: 14827  TASK: ffff881686a9af80  CPU: 20  COMMAND: "ora_p005_hrltd9"
   #0  __schedule at ffffffff818667cc
   #1  schedule at ffffffff81866de6
   #2  inode_dio_wait at ffffffff812a2d04
   #3  ocfs2_setattr at ffffffffc05f322e [ocfs2]
   #4  notify_change at ffffffff812a5a09
   #5  do_truncate at ffffffff812808f5
   #6  do_sys_ftruncate.constprop.18 at ffffffff81280cf2
   #7  sys_ftruncate at ffffffff81280d8e
   #8  do_syscall_64 at ffffffff81003949
   #9  entry_SYSCALL_64_after_hwframe at ffffffff81a001ad

dio completion path is going to complete one direct IO (decrement
inode->i_dio_count), but before that it hung at locking inode->i_rwsem:

   #0  __schedule+700 at ffffffff818667cc
   #1  schedule+54 at ffffffff81866de6
   #2  rwsem_down_write_failed+536 at ffffffff8186aa28
   #3  call_rwsem_down_write_failed+23 at ffffffff8185a1b7
   #4  down_write+45 at ffffffff81869c9d
   #5  ocfs2_dio_end_io_write+180 at ffffffffc05d5444 [ocfs2]
   #6  ocfs2_dio_end_io+85 at ffffffffc05d5a85 [ocfs2]
   #7  dio_complete+140 at ffffffff812c873c
   #8  dio_aio_complete_work+25 at ffffffff812c89f9
   #9  process_one_work+361 at ffffffff810b1889
  #10  worker_thread+77 at ffffffff810b233d
  #11  kthread+261 at ffffffff810b7fd5
  #12  ret_from_fork+62 at ffffffff81a0035e

Thus above forms ABBA deadlock.  The same deadlock was mentioned in
upstream commit 28f5a8a ("ocfs2: should wait dio before inode lock
in ocfs2_setattr()").  It seems that that commit only removed the
cluster lock (the victim of above dead lock) from the ABBA deadlock
party.

End-user visible effects: Process hang in truncate -> ocfs2_setattr path
and other processes hang at ocfs2_dio_end_io_write path.

This is to fix the deadlock itself.  It removes inode_lock() call from
dio completion path to remove the deadlock and add ip_alloc_sem lock in
setattr path to synchronize the inode modifications.

[wen.gang.wang@oracle.com: remove the "had_alloc_lock" as suggested]
  Link: https://lkml.kernel.org/r/20210402171344.1605-1-wen.gang.wang@oracle.com

Link: https://lkml.kernel.org/r/20210331203654.3911-1-wen.gang.wang@oracle.com
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dabrace pushed a commit that referenced this pull request Mar 17, 2022
When enabling VMD and IOMMU scalable mode, the following kernel panic
call trace/kernel log is shown in Eagle Stream platform (Sapphire Rapids
CPU) during booting:

pci 0000:59:00.5: Adding to iommu group 42
...
vmd 0000:59:00.5: PCI host bridge to bus 10000:80
pci 10000:80:01.0: [8086:352a] type 01 class 0x060400
pci 10000:80:01.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:01.0: enabling Extended Tags
pci 10000:80:01.0: PME# supported from D0 D3hot D3cold
pci 10000:80:01.0: DMAR: Setup RID2PASID failed
pci 10000:80:01.0: Failed to add to iommu group 42: -16
pci 10000:80:03.0: [8086:352b] type 01 class 0x060400
pci 10000:80:03.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit]
pci 10000:80:03.0: enabling Extended Tags
pci 10000:80:03.0: PME# supported from D0 D3hot D3cold
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:29!
invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.17.0-rc3+ #7
Hardware name: Lenovo ThinkSystem SR650V3/SB27A86647, BIOS ESE101Y-1.00 01/13/2022
Workqueue: events work_for_cpu_fn
RIP: 0010:__list_add_valid.cold+0x26/0x3f
Code: 9a 4a ab ff 4c 89 c1 48 c7 c7 40 0c d9 9e e8 b9 b1 fe ff 0f
      0b 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 f0 0c d9 9e e8 a2 b1
      fe ff <0f> 0b 48 89 d1 4c 89 c6 4c 89 ca 48 c7 c7 98 0c d9
      9e e8 8b b1 fe
RSP: 0000:ff5ad434865b3a40 EFLAGS: 00010246
RAX: 0000000000000058 RBX: ff4d61160b74b880 RCX: ff4d61255e1fffa8
RDX: 0000000000000000 RSI: 00000000fffeffff RDI: ffffffff9fd34f20
RBP: ff4d611d8e245c00 R08: 0000000000000000 R09: ff5ad434865b3888
R10: ff5ad434865b3880 R11: ff4d61257fdc6fe8 R12: ff4d61160b74b8a0
R13: ff4d61160b74b8a0 R14: ff4d611d8e245c10 R15: ff4d611d8001ba70
FS:  0000000000000000(0000) GS:ff4d611d5ea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ff4d611fa1401000 CR3: 0000000aa0210001 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 intel_pasid_alloc_table+0x9c/0x1d0
 dmar_insert_one_dev_info+0x423/0x540
 ? device_to_iommu+0x12d/0x2f0
 intel_iommu_attach_device+0x116/0x290
 __iommu_attach_device+0x1a/0x90
 iommu_group_add_device+0x190/0x2c0
 __iommu_probe_device+0x13e/0x250
 iommu_probe_device+0x24/0x150
 iommu_bus_notifier+0x69/0x90
 blocking_notifier_call_chain+0x5a/0x80
 device_add+0x3db/0x7b0
 ? arch_memremap_can_ram_remap+0x19/0x50
 ? memremap+0x75/0x140
 pci_device_add+0x193/0x1d0
 pci_scan_single_device+0xb9/0xf0
 pci_scan_slot+0x4c/0x110
 pci_scan_child_bus_extend+0x3a/0x290
 vmd_enable_domain.constprop.0+0x63e/0x820
 vmd_probe+0x163/0x190
 local_pci_probe+0x42/0x80
 work_for_cpu_fn+0x13/0x20
 process_one_work+0x1e2/0x3b0
 worker_thread+0x1c4/0x3a0
 ? rescuer_thread+0x370/0x370
 kthread+0xc7/0xf0
 ? kthread_complete_and_exit+0x20/0x20
 ret_from_fork+0x1f/0x30
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
...
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x1ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception ]---

The following 'lspci' output shows devices '10000:80:*' are subdevices of
the VMD device 0000:59:00.5:

  $ lspci
  ...
  0000:59:00.5 RAID bus controller: Intel Corporation Volume Management Device NVMe RAID Controller (rev 20)
  ...
  10000:80:01.0 PCI bridge: Intel Corporation Device 352a (rev 03)
  10000:80:03.0 PCI bridge: Intel Corporation Device 352b (rev 03)
  10000:80:05.0 PCI bridge: Intel Corporation Device 352c (rev 03)
  10000:80:07.0 PCI bridge: Intel Corporation Device 352d (rev 03)
  10000:81:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller]
  10000:82:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller]

The symptom 'list_add double add' is caused by the following failure
message:

  pci 10000:80:01.0: DMAR: Setup RID2PASID failed
  pci 10000:80:01.0: Failed to add to iommu group 42: -16
  pci 10000:80:03.0: [8086:352b] type 01 class 0x060400

Device 10000:80:01.0 is the subdevice of the VMD device 0000:59:00.5,
so invoking intel_pasid_alloc_table() gets the pasid_table of the VMD
device 0000:59:00.5. Here is call path:

  intel_pasid_alloc_table
    pci_for_each_dma_alias
     get_alias_pasid_table
       search_pasid_table

pci_real_dma_dev() in pci_for_each_dma_alias() gets the real dma device
which is the VMD device 0000:59:00.5. However, pte of the VMD device
0000:59:00.5 has been configured during this message "pci 0000:59:00.5:
Adding to iommu group 42". So, the status -EBUSY is returned when
configuring pasid entry for device 10000:80:01.0.

It then invokes dmar_remove_one_dev_info() to release
'struct device_domain_info *' from iommu_devinfo_cache. But, the pasid
table is not released because of the following statement in
__dmar_remove_one_dev_info():

	if (info->dev && !dev_is_real_dma_subdevice(info->dev)) {
		...
		intel_pasid_free_table(info->dev);
        }

The subsequent dmar_insert_one_dev_info() operation of device
10000:80:03.0 allocates 'struct device_domain_info *' from
iommu_devinfo_cache. The allocated address is the same address that
is released previously for device 10000:80:01.0. Finally, invoking
device_attach_pasid_table() causes the issue.

`git bisect` points to the offending commit 474dd1c ("iommu/vt-d:
Fix clearing real DMA device's scalable-mode context entries"), which
releases the pasid table if the device is not the subdevice by
checking the returned status of dev_is_real_dma_subdevice().
Reverting the offending commit can work around the issue.

The solution is to prevent from allocating pasid table if those
devices are subdevices of the VMD device.

Fixes: 474dd1c ("iommu/vt-d: Fix clearing real DMA device's scalable-mode context entries")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Adrian Huang <ahuang12@lenovo.com>
Link: https://lore.kernel.org/r/20220216091307.703-1-adrianhuang0701@gmail.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220221053348.262724-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
dabrace pushed a commit that referenced this pull request Mar 17, 2022
When "debugfs=off" is used on the kernel command line, iwiwifi's
mvm module uses an invalid/unchecked debugfs_dir pointer and causes
a BUG:

 BUG: kernel NULL pointer dereference, address: 000000000000004f
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: 0000 [#1] PREEMPT SMP
 CPU: 1 PID: 503 Comm: modprobe Tainted: G        W         5.17.0-rc5 #7
 Hardware name: Dell Inc. Inspiron 15 5510/076F7Y, BIOS 2.4.1 11/05/2021
 RIP: 0010:iwl_mvm_dbgfs_register+0x692/0x700 [iwlmvm]
 Code: 69 a0 be 80 01 00 00 48 c7 c7 50 73 6a a0 e8 95 cf ee e0 48 8b 83 b0 1e 00 00 48 c7 c2 54 73 6a a0 be 64 00 00 00 48 8d 7d 8c <48> 8b 48 50 e8 15 22 07 e1 48 8b 43 28 48 8d 55 8c 48 c7 c7 5f 73
 RSP: 0018:ffffc90000a0ba68 EFLAGS: 00010246
 RAX: ffffffffffffffff RBX: ffff88817d6e3328 RCX: ffff88817d6e3328
 RDX: ffffffffa06a7354 RSI: 0000000000000064 RDI: ffffc90000a0ba6c
 RBP: ffffc90000a0bae0 R08: ffffffff824e4880 R09: ffffffffa069d620
 R10: ffffc90000a0ba00 R11: ffffffffffffffff R12: 0000000000000000
 R13: ffffc90000a0bb28 R14: ffff88817d6e3328 R15: ffff88817d6e3320
 FS:  00007f64dd92d740(0000) GS:ffff88847f640000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 000000000000004f CR3: 000000016fc79001 CR4: 0000000000770ee0
 PKRU: 55555554
 Call Trace:
  <TASK>
  ? iwl_mvm_mac_setup_register+0xbdc/0xda0 [iwlmvm]
  iwl_mvm_start_post_nvm+0x71/0x100 [iwlmvm]
  iwl_op_mode_mvm_start+0xab8/0xb30 [iwlmvm]
  _iwl_op_mode_start+0x6f/0xd0 [iwlwifi]
  iwl_opmode_register+0x6a/0xe0 [iwlwifi]
  ? 0xffffffffa0231000
  iwl_mvm_init+0x35/0x1000 [iwlmvm]
  ? 0xffffffffa0231000
  do_one_initcall+0x5a/0x1b0
  ? kmem_cache_alloc+0x1e5/0x2f0
  ? do_init_module+0x1e/0x220
  do_init_module+0x48/0x220
  load_module+0x2602/0x2bc0
  ? __kernel_read+0x145/0x2e0
  ? kernel_read_file+0x229/0x290
  __do_sys_finit_module+0xc5/0x130
  ? __do_sys_finit_module+0xc5/0x130
  __x64_sys_finit_module+0x13/0x20
  do_syscall_64+0x38/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7f64dda564dd
 Code: 5b 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 1b 29 0f 00 f7 d8 64 89 01 48
 RSP: 002b:00007ffdba393f88 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f64dda564dd
 RDX: 0000000000000000 RSI: 00005575399e2ab2 RDI: 0000000000000001
 RBP: 000055753a91c5e0 R08: 0000000000000000 R09: 0000000000000002
 R10: 0000000000000001 R11: 0000000000000246 R12: 00005575399e2ab2
 R13: 000055753a91ceb0 R14: 0000000000000000 R15: 000055753a923018
  </TASK>
 Modules linked in: btintel(+) btmtk bluetooth vfat snd_hda_codec_hdmi fat snd_hda_codec_realtek snd_hda_codec_generic iwlmvm(+) snd_sof_pci_intel_tgl mac80211 snd_sof_intel_hda_common soundwire_intel soundwire_generic_allocation soundwire_cadence soundwire_bus snd_sof_intel_hda snd_sof_pci snd_sof snd_sof_xtensa_dsp snd_soc_hdac_hda snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi snd_soc_core btrfs snd_compress snd_hda_intel snd_intel_dspcfg snd_intel_sdw_acpi snd_hda_codec raid6_pq iwlwifi snd_hda_core snd_pcm snd_timer snd soundcore cfg80211 intel_ish_ipc(+) thunderbolt rfkill intel_ishtp ucsi_acpi wmi i2c_hid_acpi i2c_hid evdev
 CR2: 000000000000004f
 ---[ end trace 0000000000000000 ]---

Check the debugfs_dir pointer for an error before using it.

Fixes: 8c082a9 ("iwlwifi: mvm: simplify iwl_mvm_dbgfs_register")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Luca Coelho <luciano.coelho@intel.com>
Cc: linux-wireless@vger.kernel.org
Cc: Kalle Valo <kvalo@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220223030630.23241-1-rdunlap@infradead.org
[change to make both conditional]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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