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source code hm note 1s???? #29

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miuipower opened this issue Sep 1, 2015 · 0 comments
Open

source code hm note 1s???? #29

miuipower opened this issue Sep 1, 2015 · 0 comments

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@miuipower
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Hello good I wanted to ask when the kernel source code hm note 1s will be available? thank you very much xiaomi. excuse my English translator use
bgcngm pushed a commit to Mi5Devs/android_kernel_xiaomi_msm8996 that referenced this issue Oct 8, 2016
@sashalevin
mm, vmscan: Do not wait for page writeback for GFP_NOFS allocations
1f020ce 
[ Upstream commit ecf5fc6 ]

Nikolay has reported a hang when a memcg reclaim got stuck with the
following backtrace:

PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
  #0 __schedule at ffffffff815ab152
  #1 schedule at ffffffff815ab76e
  #2 schedule_timeout at ffffffff815ae5e5
  MiCode#3 io_schedule_timeout at ffffffff815aad6a
  MiCode#4 bit_wait_io at ffffffff815abfc6
  MiCode#5 __wait_on_bit at ffffffff815abda5
  MiCode#6 wait_on_page_bit at ffffffff8111fd4f
  MiCode#7 shrink_page_list at ffffffff81135445
  MiCode#8 shrink_inactive_list at ffffffff81135845
  MiCode#9 shrink_lruvec at ffffffff81135ead
 MiCode#10 shrink_zone at ffffffff811360c3
 MiCode#11 shrink_zones at ffffffff81136eff
 MiCode#12 do_try_to_free_pages at ffffffff8113712f
 MiCode#13 try_to_free_mem_cgroup_pages at ffffffff811372be
 MiCode#14 try_charge at ffffffff81189423
 MiCode#15 mem_cgroup_try_charge at ffffffff8118c6f5
 MiCode#16 __add_to_page_cache_locked at ffffffff8112137d
 MiCode#17 add_to_page_cache_lru at ffffffff81121618
 MiCode#18 pagecache_get_page at ffffffff8112170b
 MiCode#19 grow_dev_page at ffffffff811c8297
 MiCode#20 __getblk_slow at ffffffff811c91d6
 MiCode#21 __getblk_gfp at ffffffff811c92c1
 MiCode#22 ext4_ext_grow_indepth at ffffffff8124565c
 MiCode#23 ext4_ext_create_new_leaf at ffffffff81246ca8
 MiCode#24 ext4_ext_insert_extent at ffffffff81246f09
 MiCode#25 ext4_ext_map_blocks at ffffffff8124a848
 MiCode#26 ext4_map_blocks at ffffffff8121a5b7
 MiCode#27 mpage_map_one_extent at ffffffff8121b1fa
 MiCode#28 mpage_map_and_submit_extent at ffffffff8121f07b
 MiCode#29 ext4_writepages at ffffffff8121f6d5
 MiCode#30 do_writepages at ffffffff8112c490
 MiCode#31 __filemap_fdatawrite_range at ffffffff81120199
 MiCode#32 filemap_flush at ffffffff8112041c
 MiCode#33 ext4_alloc_da_blocks at ffffffff81219da1
 MiCode#34 ext4_rename at ffffffff81229b91
 MiCode#35 ext4_rename2 at ffffffff81229e32
 MiCode#36 vfs_rename at ffffffff811a08a5
 MiCode#37 SYSC_renameat2 at ffffffff811a3ffc
 MiCode#38 sys_renameat2 at ffffffff811a408e
 MiCode#39 sys_rename at ffffffff8119e51e
 MiCode#40 system_call_fastpath at ffffffff815afa89

Dave Chinner has properly pointed out that this is a deadlock in the
reclaim code because ext4 doesn't submit pages which are marked by
PG_writeback right away.

The heuristic was introduced by commit e62e384 ("memcg: prevent OOM
with too many dirty pages") and it was applied only when may_enter_fs
was specified.  The code has been changed by c3b94f4 ("memcg:
further prevent OOM with too many dirty pages") which has removed the
__GFP_FS restriction with a reasoning that we do not get into the fs
code.  But this is not sufficient apparently because the fs doesn't
necessarily submit pages marked PG_writeback for IO right away.

ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
submit the bio.  Instead it tries to map more pages into the bio and
mpage_map_one_extent might trigger memcg charge which might end up
waiting on a page which is marked PG_writeback but hasn't been submitted
yet so we would end up waiting for something that never finishes.

Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
before we go to wait on the writeback.  The page fault path, which is
the only path that triggers memcg oom killer since 3.12, shouldn't
require GFP_NOFS and so we shouldn't reintroduce the premature OOM
killer issue which was originally addressed by the heuristic.

As per David Chinner the xfs is doing similar thing since 2.6.15 already
so ext4 is not the only affected filesystem.  Moreover he notes:

: For example: IO completion might require unwritten extent conversion
: which executes filesystem transactions and GFP_NOFS allocations. The
: writeback flag on the pages can not be cleared until unwritten
: extent conversion completes. Hence memory reclaim cannot wait on
: page writeback to complete in GFP_NOFS context because it is not
: safe to do so, memcg reclaim or otherwise.

Cc: stable@vger.kernel.org # 3.9+
[tytso@mit.edu: corrected the control flow]
Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages")
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
mihirshah006 pushed a commit to mihirshah006/Xiaomi_Kernel_OpenSource that referenced this issue Jul 25, 2017
@mihirshah006
mm, vmscan: Do not wait for page writeback for GFP_NOFS allocations
22f6c6f 
commit ecf5fc6 upstream.

Nikolay has reported a hang when a memcg reclaim got stuck with the
following backtrace:

PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
  #0 __schedule at ffffffff815ab152
  premaca#1 schedule at ffffffff815ab76e
  premaca#2 schedule_timeout at ffffffff815ae5e5
  MiCode#3 io_schedule_timeout at ffffffff815aad6a
  MiCode#4 bit_wait_io at ffffffff815abfc6
  MiCode#5 __wait_on_bit at ffffffff815abda5
  MiCode#6 wait_on_page_bit at ffffffff8111fd4f
  MiCode#7 shrink_page_list at ffffffff81135445
  MiCode#8 shrink_inactive_list at ffffffff81135845
  MiCode#9 shrink_lruvec at ffffffff81135ead
 MiCode#10 shrink_zone at ffffffff811360c3
 MiCode#11 shrink_zones at ffffffff81136eff
 MiCode#12 do_try_to_free_pages at ffffffff8113712f
 MiCode#13 try_to_free_mem_cgroup_pages at ffffffff811372be
 MiCode#14 try_charge at ffffffff81189423
 MiCode#15 mem_cgroup_try_charge at ffffffff8118c6f5
 MiCode#16 __add_to_page_cache_locked at ffffffff8112137d
 MiCode#17 add_to_page_cache_lru at ffffffff81121618
 MiCode#18 pagecache_get_page at ffffffff8112170b
 MiCode#19 grow_dev_page at ffffffff811c8297
 MiCode#20 __getblk_slow at ffffffff811c91d6
 MiCode#21 __getblk_gfp at ffffffff811c92c1
 MiCode#22 ext4_ext_grow_indepth at ffffffff8124565c
 MiCode#23 ext4_ext_create_new_leaf at ffffffff81246ca8
 MiCode#24 ext4_ext_insert_extent at ffffffff81246f09
 MiCode#25 ext4_ext_map_blocks at ffffffff8124a848
 MiCode#26 ext4_map_blocks at ffffffff8121a5b7
 MiCode#27 mpage_map_one_extent at ffffffff8121b1fa
 MiCode#28 mpage_map_and_submit_extent at ffffffff8121f07b
 MiCode#29 ext4_writepages at ffffffff8121f6d5
 MiCode#30 do_writepages at ffffffff8112c490
 MiCode#31 __filemap_fdatawrite_range at ffffffff81120199
 MiCode#32 filemap_flush at ffffffff8112041c
 MiCode#33 ext4_alloc_da_blocks at ffffffff81219da1
 MiCode#34 ext4_rename at ffffffff81229b91
 MiCode#35 ext4_rename2 at ffffffff81229e32
 MiCode#36 vfs_rename at ffffffff811a08a5
 MiCode#37 SYSC_renameat2 at ffffffff811a3ffc
 MiCode#38 sys_renameat2 at ffffffff811a408e
 MiCode#39 sys_rename at ffffffff8119e51e
 MiCode#40 system_call_fastpath at ffffffff815afa89

Dave Chinner has properly pointed out that this is a deadlock in the
reclaim code because ext4 doesn't submit pages which are marked by
PG_writeback right away.

The heuristic was introduced by commit e62e384 ("memcg: prevent OOM
with too many dirty pages") and it was applied only when may_enter_fs
was specified.  The code has been changed by c3b94f4 ("memcg:
further prevent OOM with too many dirty pages") which has removed the
__GFP_FS restriction with a reasoning that we do not get into the fs
code.  But this is not sufficient apparently because the fs doesn't
necessarily submit pages marked PG_writeback for IO right away.

ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
submit the bio.  Instead it tries to map more pages into the bio and
mpage_map_one_extent might trigger memcg charge which might end up
waiting on a page which is marked PG_writeback but hasn't been submitted
yet so we would end up waiting for something that never finishes.

Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
before we go to wait on the writeback.  The page fault path, which is
the only path that triggers memcg oom killer since 3.12, shouldn't
require GFP_NOFS and so we shouldn't reintroduce the premature OOM
killer issue which was originally addressed by the heuristic.

As per David Chinner the xfs is doing similar thing since 2.6.15 already
so ext4 is not the only affected filesystem.  Moreover he notes:

: For example: IO completion might require unwritten extent conversion
: which executes filesystem transactions and GFP_NOFS allocations. The
: writeback flag on the pages can not be cleared until unwritten
: extent conversion completes. Hence memory reclaim cannot wait on
: page writeback to complete in GFP_NOFS context because it is not
: safe to do so, memcg reclaim or otherwise.

[tytso@mit.edu: corrected the control flow]
Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages")
Reported-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[@MSF-Jarvis: Fix conflicts from "mm: vmscan: stall page reclaim after a list of pages have been processed" ]

Change-Id: I09aa7c565388b4b323034d5c71a463f4fb175462
ronaldichandra pushed a commit to ronaldichandra/kernel_xiaomi_ginkgo that referenced this issue Oct 26, 2019
@gregkh
fsl/fman: Use GFP_ATOMIC in {memac,tgec}_add_hash_mac_address()
922c8a5 
[ Upstream commit 0d9c9a2 ]

These functions are called from atomic context:

[    9.150239] BUG: sleeping function called from invalid context at /home/scott/git/linux/mm/slab.h:421
[    9.158159] in_atomic(): 1, irqs_disabled(): 0, pid: 4432, name: ip
[    9.163128] CPU: 8 PID: 4432 Comm: ip Not tainted 4.20.0-rc2-00169-g63d86876f324 MiCode#29
[    9.163130] Call Trace:
[    9.170701] [c0000002e899a980] [c0000000009c1068] .dump_stack+0xa8/0xec (unreliable)
[    9.177140] [c0000002e899aa10] [c00000000007a7b4] .___might_sleep+0x138/0x164
[    9.184440] [c0000002e899aa80] [c0000000001d5bac] .kmem_cache_alloc_trace+0x238/0x30c
[    9.191216] [c0000002e899ab40] [c00000000065ea1c] .memac_add_hash_mac_address+0x104/0x198
[    9.199464] [c0000002e899abd0] [c00000000065a788] .set_multi+0x1c8/0x218
[    9.206242] [c0000002e899ac80] [c0000000006615ec] .dpaa_set_rx_mode+0xdc/0x17c
[    9.213544] [c0000002e899ad00] [c00000000083d2b0] .__dev_set_rx_mode+0x80/0xd4
[    9.219535] [c0000002e899ad90] [c00000000083d334] .dev_set_rx_mode+0x30/0x54
[    9.225271] [c0000002e899ae10] [c00000000083d4a0] .__dev_open+0x148/0x1c8
[    9.230751] [c0000002e899aeb0] [c00000000083d934] .__dev_change_flags+0x19c/0x1e0
[    9.230755] [c0000002e899af60] [c00000000083d9a4] .dev_change_flags+0x2c/0x80
[    9.242752] [c0000002e899aff0] [c0000000008554ec] .do_setlink+0x350/0xf08
[    9.248228] [c0000002e899b170] [c000000000857ad0] .rtnl_newlink+0x588/0x7e0
[    9.253965] [c0000002e899b740] [c000000000852424] .rtnetlink_rcv_msg+0x3e0/0x498
[    9.261440] [c0000002e899b820] [c000000000884790] .netlink_rcv_skb+0x134/0x14c
[    9.267607] [c0000002e899b8e0] [c000000000851840] .rtnetlink_rcv+0x18/0x2c
[    9.274558] [c0000002e899b950] [c000000000883c8c] .netlink_unicast+0x214/0x318
[    9.281163] [c0000002e899ba00] [c000000000884220] .netlink_sendmsg+0x348/0x444
[    9.287076] [c0000002e899bae0] [c00000000080d13c] .sock_sendmsg+0x2c/0x54
[    9.287080] [c0000002e899bb50] [c0000000008106c0] .___sys_sendmsg+0x2d0/0x2d8
[    9.298375] [c0000002e899bd30] [c000000000811a80] .__sys_sendmsg+0x5c/0xb0
[    9.303939] [c0000002e899be20] [c0000000000006b0] system_call+0x60/0x6c

Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
pix106 pushed a commit to pix106/android_kernel_xiaomi that referenced this issue Aug 24, 2020
@idosch @gregkh
vxlan: Ensure FDB dump is performed under RCU
a2cbcfc 
[ Upstream commit b514191 ]

The commit cited below removed the RCU read-side critical section from
rtnl_fdb_dump() which means that the ndo_fdb_dump() callback is invoked
without RCU protection.

This results in the following warning [1] in the VXLAN driver, which
relied on the callback being invoked from an RCU read-side critical
section.

Fix this by calling rcu_read_lock() in the VXLAN driver, as already done
in the bridge driver.

[1]
WARNING: suspicious RCU usage
5.8.0-rc4-custom-01521-g481007553ce6 MiCode#29 Not tainted
-----------------------------
drivers/net/vxlan.c:1379 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by bridge/166:
 #0: ffffffff85a27850 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xea/0x1090

stack backtrace:
CPU: 1 PID: 166 Comm: bridge Not tainted 5.8.0-rc4-custom-01521-g481007553ce6 MiCode#29
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014
Call Trace:
 dump_stack+0x100/0x184
 lockdep_rcu_suspicious+0x153/0x15d
 vxlan_fdb_dump+0x51e/0x6d0
 rtnl_fdb_dump+0x4dc/0xad0
 netlink_dump+0x540/0x1090
 __netlink_dump_start+0x695/0x950
 rtnetlink_rcv_msg+0x802/0xbd0
 netlink_rcv_skb+0x17a/0x480
 rtnetlink_rcv+0x22/0x30
 netlink_unicast+0x5ae/0x890
 netlink_sendmsg+0x98a/0xf40
 __sys_sendto+0x279/0x3b0
 __x64_sys_sendto+0xe6/0x1a0
 do_syscall_64+0x54/0xa0
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fe14fa2ade0
Code: Bad RIP value.
RSP: 002b:00007fff75bb5b88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005614b1ba0020 RCX: 00007fe14fa2ade0
RDX: 000000000000011c RSI: 00007fff75bb5b90 RDI: 0000000000000003
RBP: 00007fff75bb5b90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00005614b1b89160
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Fixes: 5e6d243 ("bridge: netlink dump interface at par with brctl")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
pix106 pushed a commit to pix106/android_kernel_xiaomi that referenced this issue Oct 1, 2020
@howardchungg @gregkh
Bluetooth: L2CAP: handle l2cap config request during open state
4ad03ff 
[ Upstream commit 96298f6 ]

According to Core Spec Version 5.2 | Vol 3, Part A 6.1.5,
the incoming L2CAP_ConfigReq should be handled during
OPEN state.

The section below shows the btmon trace when running
L2CAP/COS/CFD/BV-12-C before and after this change.

=== Before ===
...
> ACL Data RX: Handle 256 flags 0x02 dlen 12                MiCode#22
      L2CAP: Connection Request (0x02) ident 2 len 4
        PSM: 1 (0x0001)
        Source CID: 65
< ACL Data TX: Handle 256 flags 0x00 dlen 16                MiCode#23
      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 256 flags 0x00 dlen 12                MiCode#24
      L2CAP: Configure Request (0x04) ident 2 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#25
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#26
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 16                MiCode#27
      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00                                            ..
< ACL Data TX: Handle 256 flags 0x00 dlen 18                MiCode#28
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#29
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 14                MiCode#30
      L2CAP: Configure Response (0x05) ident 2 len 6
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
> ACL Data RX: Handle 256 flags 0x02 dlen 20                MiCode#31
      L2CAP: Configure Request (0x04) ident 3 len 12
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00 91 02 11 11                                ......
< ACL Data TX: Handle 256 flags 0x00 dlen 14                MiCode#32
      L2CAP: Command Reject (0x01) ident 3 len 6
        Reason: Invalid CID in request (0x0002)
        Destination CID: 64
        Source CID: 65
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#33
        Num handles: 1
        Handle: 256
        Count: 1
...
=== After ===
...
> ACL Data RX: Handle 256 flags 0x02 dlen 12               MiCode#22
      L2CAP: Connection Request (0x02) ident 2 len 4
        PSM: 1 (0x0001)
        Source CID: 65
< ACL Data TX: Handle 256 flags 0x00 dlen 16               MiCode#23
      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 256 flags 0x00 dlen 12               MiCode#24
      L2CAP: Configure Request (0x04) ident 2 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#25
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#26
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 16               MiCode#27
      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00                                            ..
< ACL Data TX: Handle 256 flags 0x00 dlen 18               MiCode#28
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#29
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 14               MiCode#30
      L2CAP: Configure Response (0x05) ident 2 len 6
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
> ACL Data RX: Handle 256 flags 0x02 dlen 20               MiCode#31
      L2CAP: Configure Request (0x04) ident 3 len 12
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00 91 02 11 11                                .....
< ACL Data TX: Handle 256 flags 0x00 dlen 18               MiCode#32
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
< ACL Data TX: Handle 256 flags 0x00 dlen 12               MiCode#33
      L2CAP: Configure Request (0x04) ident 3 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#34
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#35
        Num handles: 1
        Handle: 256
        Count: 1
...

Signed-off-by: Howard Chung <howardchung@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
hectorvax pushed a commit to hectorvax/Xiaomi_Kernel_OpenSource that referenced this issue Jan 3, 2023
@idosch @gregkh
vxlan: Ensure FDB dump is performed under RCU
49a3f51 
[ Upstream commit b514191 ]

The commit cited below removed the RCU read-side critical section from
rtnl_fdb_dump() which means that the ndo_fdb_dump() callback is invoked
without RCU protection.

This results in the following warning [1] in the VXLAN driver, which
relied on the callback being invoked from an RCU read-side critical
section.

Fix this by calling rcu_read_lock() in the VXLAN driver, as already done
in the bridge driver.

[1]
WARNING: suspicious RCU usage
5.8.0-rc4-custom-01521-g481007553ce6 MiCode#29 Not tainted
-----------------------------
drivers/net/vxlan.c:1379 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by bridge/166:
 #0: ffffffff85a27850 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xea/0x1090

stack backtrace:
CPU: 1 PID: 166 Comm: bridge Not tainted 5.8.0-rc4-custom-01521-g481007553ce6 MiCode#29
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014
Call Trace:
 dump_stack+0x100/0x184
 lockdep_rcu_suspicious+0x153/0x15d
 vxlan_fdb_dump+0x51e/0x6d0
 rtnl_fdb_dump+0x4dc/0xad0
 netlink_dump+0x540/0x1090
 __netlink_dump_start+0x695/0x950
 rtnetlink_rcv_msg+0x802/0xbd0
 netlink_rcv_skb+0x17a/0x480
 rtnetlink_rcv+0x22/0x30
 netlink_unicast+0x5ae/0x890
 netlink_sendmsg+0x98a/0xf40
 __sys_sendto+0x279/0x3b0
 __x64_sys_sendto+0xe6/0x1a0
 do_syscall_64+0x54/0xa0
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fe14fa2ade0
Code: Bad RIP value.
RSP: 002b:00007fff75bb5b88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00005614b1ba0020 RCX: 00007fe14fa2ade0
RDX: 000000000000011c RSI: 00007fff75bb5b90 RDI: 0000000000000003
RBP: 00007fff75bb5b90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00005614b1b89160
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Fixes: 5e6d243 ("bridge: netlink dump interface at par with brctl")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hectorvax pushed a commit to hectorvax/Xiaomi_Kernel_OpenSource that referenced this issue Jan 3, 2023
@howardchungg @gregkh
Bluetooth: L2CAP: handle l2cap config request during open state
799263e 
[ Upstream commit 96298f6 ]

According to Core Spec Version 5.2 | Vol 3, Part A 6.1.5,
the incoming L2CAP_ConfigReq should be handled during
OPEN state.

The section below shows the btmon trace when running
L2CAP/COS/CFD/BV-12-C before and after this change.

=== Before ===
...
> ACL Data RX: Handle 256 flags 0x02 dlen 12                MiCode#22
      L2CAP: Connection Request (0x02) ident 2 len 4
        PSM: 1 (0x0001)
        Source CID: 65
< ACL Data TX: Handle 256 flags 0x00 dlen 16                MiCode#23
      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 256 flags 0x00 dlen 12                MiCode#24
      L2CAP: Configure Request (0x04) ident 2 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#25
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#26
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 16                MiCode#27
      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00                                            ..
< ACL Data TX: Handle 256 flags 0x00 dlen 18                MiCode#28
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#29
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 14                MiCode#30
      L2CAP: Configure Response (0x05) ident 2 len 6
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
> ACL Data RX: Handle 256 flags 0x02 dlen 20                MiCode#31
      L2CAP: Configure Request (0x04) ident 3 len 12
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00 91 02 11 11                                ......
< ACL Data TX: Handle 256 flags 0x00 dlen 14                MiCode#32
      L2CAP: Command Reject (0x01) ident 3 len 6
        Reason: Invalid CID in request (0x0002)
        Destination CID: 64
        Source CID: 65
> HCI Event: Number of Completed Packets (0x13) plen 5      MiCode#33
        Num handles: 1
        Handle: 256
        Count: 1
...
=== After ===
...
> ACL Data RX: Handle 256 flags 0x02 dlen 12               MiCode#22
      L2CAP: Connection Request (0x02) ident 2 len 4
        PSM: 1 (0x0001)
        Source CID: 65
< ACL Data TX: Handle 256 flags 0x00 dlen 16               MiCode#23
      L2CAP: Connection Response (0x03) ident 2 len 8
        Destination CID: 64
        Source CID: 65
        Result: Connection successful (0x0000)
        Status: No further information available (0x0000)
< ACL Data TX: Handle 256 flags 0x00 dlen 12               MiCode#24
      L2CAP: Configure Request (0x04) ident 2 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#25
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#26
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 16               MiCode#27
      L2CAP: Configure Request (0x04) ident 3 len 8
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00                                            ..
< ACL Data TX: Handle 256 flags 0x00 dlen 18               MiCode#28
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#29
        Num handles: 1
        Handle: 256
        Count: 1
> ACL Data RX: Handle 256 flags 0x02 dlen 14               MiCode#30
      L2CAP: Configure Response (0x05) ident 2 len 6
        Source CID: 64
        Flags: 0x0000
        Result: Success (0x0000)
> ACL Data RX: Handle 256 flags 0x02 dlen 20               MiCode#31
      L2CAP: Configure Request (0x04) ident 3 len 12
        Destination CID: 64
        Flags: 0x0000
        Option: Unknown (0x10) [hint]
        01 00 91 02 11 11                                .....
< ACL Data TX: Handle 256 flags 0x00 dlen 18               MiCode#32
      L2CAP: Configure Response (0x05) ident 3 len 10
        Source CID: 65
        Flags: 0x0000
        Result: Success (0x0000)
        Option: Maximum Transmission Unit (0x01) [mandatory]
          MTU: 672
< ACL Data TX: Handle 256 flags 0x00 dlen 12               MiCode#33
      L2CAP: Configure Request (0x04) ident 3 len 4
        Destination CID: 65
        Flags: 0x0000
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#34
        Num handles: 1
        Handle: 256
        Count: 1
> HCI Event: Number of Completed Packets (0x13) plen 5     MiCode#35
        Num handles: 1
        Handle: 256
        Count: 1
...

Signed-off-by: Howard Chung <howardchung@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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