Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fib6_walk_continue: Unable to handle kernel paging request at virtual address 12005456 #11

Open
legoater opened this issue Jul 7, 2017 · 0 comments

Comments

@legoater
Copy link

legoater commented Jul 7, 2017

I've seen this panic with 6d93f62 a number of times under qemu's palmetto-bmc machine. Unsure at this stage whether it's the kernel or something qemu is doing wrong and I admit my qemu build is a bit of a mashup, but here's the panic output:

Unable to handle kernel paging request at virtual address 12005456
pgd = c0004000
[12005456] *pgd=00000000
Internal error: Oops: 5 [#1] ARM
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 4.7.1-00053-g6d93f625315a-dirty #579
Hardware name: ASpeed SoC
task: c040c700 ti: c0408000 task.ti: c0408000
PC is at fib6_walk_continue+0x74/0x168
LR is at fib6_clean_node+0xb8/0x160
pc : [<c02991d0>]    lr : [<c029af0c>]    psr: 80000113
sp : c0409d90  ip : 00000001  fp : c8c0f280
r10: c029ae54  r9 : c02992dc  r8 : 00000000
r7 : c0409e34  r6 : 00000633  r5 : 00000002  r4 : c0409dc8
r3 : 12005452  r2 : 00000000  r1 : c8e31b60  r0 : 00000000
Flags: Nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 00093177  Table: 48da0000  DAC: 00000051
Process swapper (pid: 0, stack limit = 0xc0408190)
Stack: (0xc0409d90 to 0xc040a000)
9d80:                                     c0409dc8 c0422908 c0422d28 c02998b8
9da0: 00000000 c040a028 c0422908 c0299c40 00000000 00000000 c0299b9c 60000193
9dc0: c040ca88 c8c0f28c c0422cd4 c0422cd4 c8c0f2a8 12005452 c8fafaa0 00000000
9de0: c040ca00 00000000 00000004 c029ae54 c0426e50 c0422908 c02992dc 00000000
9e00: c0409e34 dc8ba501 c029785c c0422908 00000bb8 c040a028 c0422ca0 c0422d38
9e20: c0414200 c0422908 00000200 c029b040 00000001 00000bb8 00000000 dc8ba501
9e40: 00000000 c0409e74 ffffe000 c040a028 00000100 00000001 c029b0a8 c004e9c8
9e60: 00000001 00000000 c004e954 60000193 c040ca88 c09b11b4 c0577c10 00000000
9e80: c039fceb dc8ba501 c04139c0 c0414200 c0413dfc c0422ca0 c04139c0 c029b0a8
9ea0: c0422908 c004f150 c040a028 00000000 00000000 dc8ba501 00000000 c0408000
9ec0: 40000001 00200000 00000002 c042d8e0 0000000a c042d904 00000100 c0019b90
9ee0: c040c700 df407100 df40715c ffff9f29 00000002 c0414200 c042d900 00000001
9f00: c041ad24 00000000 c041ad24 00000000 df402200 00000001 dfffce80 c03f9a48
9f20: 00000000 c0019f18 00000000 c0045b10 df405020 00000001 c0409f60 00000000
9f40: 00000020 c00094a8 c000ad14 60000013 ffffffff c0409f94 c040a020 c000de30
9f60: 00000000 00093177 00092177 60000013 c0408000 00000001 ffffffff c040a028
9f80: c040a020 dfffce80 c03f9a48 00000000 600000d3 c0409fb0 c000ad08 c000ad14
9fa0: 60000013 ffffffff 00000053 c005e3e0 c0408000 c003ae58 c042d20c c03dbc4c
9fc0: ffffffff ffffffff 00000000 c03db6a8 c03f9a48 00000000 c042d334 c040a03c
9fe0: c03f9a44 c040dd24 40004000 41069265 403f7c2c 40008048 00000000 00000000
[<c02991d0>] (fib6_walk_continue) from [<c02998b8>] (fib6_walk+0x4c/0x68)
[<c02998b8>] (fib6_walk) from [<c0299c40>] (__fib6_clean_all+0xa4/0xfc)
[<c0299c40>] (__fib6_clean_all) from [<c029b040>] (fib6_run_gc+0x80/0xe8)
[<c029b040>] (fib6_run_gc) from [<c004e9c8>] (call_timer_fn+0x74/0x118)
[<c004e9c8>] (call_timer_fn) from [<c004f150>] (run_timer_softirq+0x1ac/0x1fc)
[<c004f150>] (run_timer_softirq) from [<c0019b90>] (__do_softirq+0xc0/0x1f0)
[<c0019b90>] (__do_softirq) from [<c0019f18>] (irq_exit+0x84/0xe8)
[<c0019f18>] (irq_exit) from [<c0045b10>] (__handle_domain_irq+0x84/0xa0)
[<c0045b10>] (__handle_domain_irq) from [<c00094a8>] (avic_handle_irq+0x68/0x70)
[<c00094a8>] (avic_handle_irq) from [<c000de30>] (__irq_svc+0x50/0x64)
Exception stack(0xc0409f60 to 0xc0409fa8)
9f60: 00000000 00093177 00092177 60000013 c0408000 00000001 ffffffff c040a028
9f80: c040a020 dfffce80 c03f9a48 00000000 600000d3 c0409fb0 c000ad08 c000ad14
9fa0: 60000013 ffffffff
[<c000de30>] (__irq_svc) from [<c000ad14>] (arch_cpu_idle+0x2c/0x34)
[<c000ad14>] (arch_cpu_idle) from [<c003ae58>] (cpu_startup_entry+0x7c/0xd8)
[<c003ae58>] (cpu_startup_entry) from [<c03dbc4c>] (start_kernel+0x354/0x3e0)
Code: c02991d0 c02991e4 c0299208 c0299260 (e5932004) 
---[ end trace 50fcc4bab94a343d ]---
Kernel panic - not syncing: Fatal exception in interrupt
---[ end Kernel panic - not syncing: Fatal exception in interrupt
amboar pushed a commit that referenced this issue Oct 23, 2018
if qio_channel_rdma_readv return QIO_CHANNEL_ERR_BLOCK, the destination qemu
crash.

The backtrace is:
(gdb) bt
    #0  0x0000000000000000 in ?? ()
    #1  0x00000000008db50e in qio_channel_set_aio_fd_handler (ioc=0x38111e0, ctx=0x3726080,
        io_read=0x8db841 <qio_channel_restart_read>, io_write=0x0, opaque=0x38111e0) at io/channel.c:
    #2  0x00000000008db952 in qio_channel_set_aio_fd_handlers (ioc=0x38111e0) at io/channel.c:438
    #3  0x00000000008dbab4 in qio_channel_yield (ioc=0x38111e0, condition=G_IO_IN) at io/channel.c:47
    #4  0x00000000007a870b in channel_get_buffer (opaque=0x38111e0, buf=0x440c038 "", pos=0, size=327
        at migration/qemu-file-channel.c:83
    #5  0x00000000007a70f6 in qemu_fill_buffer (f=0x440c000) at migration/qemu-file.c:299
    #6  0x00000000007a79d0 in qemu_peek_byte (f=0x440c000, offset=0) at migration/qemu-file.c:562
    #7  0x00000000007a7a22 in qemu_get_byte (f=0x440c000) at migration/qemu-file.c:575
    #8  0x00000000007a7c78 in qemu_get_be32 (f=0x440c000) at migration/qemu-file.c:655
    #9  0x00000000007a0508 in qemu_loadvm_state (f=0x440c000) at migration/savevm.c:2126
    #10 0x0000000000794141 in process_incoming_migration_co (opaque=0x0) at migration/migration.c:366
    #11 0x000000000095c598 in coroutine_trampoline (i0=84033984, i1=0) at util/coroutine-ucontext.c:1
    #12 0x00007f9c0db56d40 in ?? () from /lib64/libc.so.6
    #13 0x00007f96fe858760 in ?? ()
    #14 0x0000000000000000 in ?? ()

RDMA QIOChannel not implement io_set_aio_fd_handler. so
qio_channel_set_aio_fd_handler will access NULL pointer.

Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
when qio_channel_read return QIO_CHANNEL_ERR_BLOCK, the source qemu crash.

The backtrace is:
    (gdb) bt
    #0  0x00007fb20aba91d7 in raise () from /lib64/libc.so.6
    #1  0x00007fb20abaa8c8 in abort () from /lib64/libc.so.6
    #2  0x00007fb20aba2146 in __assert_fail_base () from /lib64/libc.so.6
    #3  0x00007fb20aba21f2 in __assert_fail () from /lib64/libc.so.6
    #4  0x00000000008dba2d in qio_channel_yield (ioc=0x22f9e20, condition=G_IO_IN) at io/channel.c:460
    #5  0x00000000007a870b in channel_get_buffer (opaque=0x22f9e20, buf=0x3d54038 "", pos=0, size=32768)
        at migration/qemu-file-channel.c:83
    #6  0x00000000007a70f6 in qemu_fill_buffer (f=0x3d54000) at migration/qemu-file.c:299
    #7  0x00000000007a79d0 in qemu_peek_byte (f=0x3d54000, offset=0) at migration/qemu-file.c:562
    #8  0x00000000007a7a22 in qemu_get_byte (f=0x3d54000) at migration/qemu-file.c:575
    #9  0x00000000007a7c46 in qemu_get_be16 (f=0x3d54000) at migration/qemu-file.c:647
    #10 0x0000000000796db7 in source_return_path_thread (opaque=0x2242280) at migration/migration.c:1794
    #11 0x00000000009428fa in qemu_thread_start (args=0x3e58420) at util/qemu-thread-posix.c:504
    #12 0x00007fb20af3ddc5 in start_thread () from /lib64/libpthread.so.0
    #13 0x00007fb20ac6b74d in clone () from /lib64/libc.so.6

This patch fixed by invoke qio_channel_yield only when qemu_in_coroutine().

Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
Because RDMA QIOChannel not implement shutdown function,
If the to_dst_file was set error, the return path thread
will wait forever. and the migration thread will wait
return path thread exit.

the backtrace of return path thread is:

(gdb) bt
    #0  0x00007f372a76bb0f in ppoll () from /lib64/libc.so.6
    #1  0x000000000071dc24 in qemu_poll_ns (fds=0x7ef7091d0580, nfds=2, timeout=100000000)
        at qemu-timer.c:325
    #2  0x00000000006b2fba in qemu_rdma_wait_comp_channel (rdma=0xd424000)
        at migration/rdma.c:1501
    #3  0x00000000006b3191 in qemu_rdma_block_for_wrid (rdma=0xd424000, wrid_requested=4000,
        byte_len=0x7ef7091d0640) at migration/rdma.c:1580
    #4  0x00000000006b3638 in qemu_rdma_exchange_get_response (rdma=0xd424000,
        head=0x7ef7091d0720, expecting=3, idx=0) at migration/rdma.c:1726
    #5  0x00000000006b3ad6 in qemu_rdma_exchange_recv (rdma=0xd424000, head=0x7ef7091d0720,
        expecting=3) at migration/rdma.c:1903
    #6  0x00000000006b5d03 in qemu_rdma_get_buffer (opaque=0x6a57dc0, buf=0x5c80030 "", pos=8,
        size=32768) at migration/rdma.c:2714
    #7  0x00000000006a9635 in qemu_fill_buffer (f=0x5c80000) at migration/qemu-file.c:232
    #8  0x00000000006a9ecd in qemu_peek_byte (f=0x5c80000, offset=0)
        at migration/qemu-file.c:502
    #9  0x00000000006a9f1f in qemu_get_byte (f=0x5c80000) at migration/qemu-file.c:515
    #10 0x00000000006aa162 in qemu_get_be16 (f=0x5c80000) at migration/qemu-file.c:591
    #11 0x00000000006a46d3 in source_return_path_thread (
        opaque=0xd826a0 <current_migration.37100>) at migration/migration.c:1331
    #12 0x00007f372aa49e25 in start_thread () from /lib64/libpthread.so.0
    #13 0x00007f372a77635d in clone () from /lib64/libc.so.6

the backtrace of migration thread is:

(gdb) bt
    #0  0x00007f372aa4af57 in pthread_join () from /lib64/libpthread.so.0
    #1  0x00000000007d5711 in qemu_thread_join (thread=0xd826f8 <current_migration.37100+88>)
        at util/qemu-thread-posix.c:504
    #2  0x00000000006a4bc5 in await_return_path_close_on_source (
        ms=0xd826a0 <current_migration.37100>) at migration/migration.c:1460
    #3  0x00000000006a53e4 in migration_completion (s=0xd826a0 <current_migration.37100>,
        current_active_state=4, old_vm_running=0x7ef7089cf976, start_time=0x7ef7089cf980)
        at migration/migration.c:1695
    #4  0x00000000006a5c54 in migration_thread (opaque=0xd826a0 <current_migration.37100>)
        at migration/migration.c:1837
    #5  0x00007f372aa49e25 in start_thread () from /lib64/libpthread.so.0
    #6  0x00007f372a77635d in clone () from /lib64/libc.so.6

Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
tests/cdrom-test -p /x86_64/cdrom/boot/megasas

Produces the following ASAN leak.

==25700==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 16 byte(s) in 1 object(s) allocated from:
    #0 0x7f06f8faac48 in malloc (/lib64/libasan.so.5+0xeec48)
    #1 0x7f06f87a73c5 in g_malloc (/lib64/libglib-2.0.so.0+0x523c5)
    #2 0x55a729f17738 in pci_dma_sglist_init /home/elmarco/src/qq/include/hw/pci/pci.h:818
    #3 0x55a729f2a706 in megasas_map_dcmd /home/elmarco/src/qq/hw/scsi/megasas.c:698
    #4 0x55a729f39421 in megasas_handle_dcmd /home/elmarco/src/qq/hw/scsi/megasas.c:1574
    #5 0x55a729f3f70d in megasas_handle_frame /home/elmarco/src/qq/hw/scsi/megasas.c:1955
    #6 0x55a729f40939 in megasas_mmio_write /home/elmarco/src/qq/hw/scsi/megasas.c:2119
    #7 0x55a729f41102 in megasas_port_write /home/elmarco/src/qq/hw/scsi/megasas.c:2170
    #8 0x55a729220e60 in memory_region_write_accessor /home/elmarco/src/qq/memory.c:527
    #9 0x55a7292212b3 in access_with_adjusted_size /home/elmarco/src/qq/memory.c:594
    #10 0x55a72922cf70 in memory_region_dispatch_write /home/elmarco/src/qq/memory.c:1473
    #11 0x55a7290f5907 in flatview_write_continue /home/elmarco/src/qq/exec.c:3255
    #12 0x55a7290f5ceb in flatview_write /home/elmarco/src/qq/exec.c:3294
    #13 0x55a7290f6457 in address_space_write /home/elmarco/src/qq/exec.c:3384
    #14 0x55a7290f64a8 in address_space_rw /home/elmarco/src/qq/exec.c:3395
    #15 0x55a72929ecb0 in kvm_handle_io /home/elmarco/src/qq/accel/kvm/kvm-all.c:1729
    #16 0x55a7292a0db5 in kvm_cpu_exec /home/elmarco/src/qq/accel/kvm/kvm-all.c:1969
    #17 0x55a7291c4212 in qemu_kvm_cpu_thread_fn /home/elmarco/src/qq/cpus.c:1215
    #18 0x55a72a966a6c in qemu_thread_start /home/elmarco/src/qq/util/qemu-thread-posix.c:504
    #19 0x7f06ed486593 in start_thread (/lib64/libpthread.so.0+0x7593)

Move the qemu_sglist_destroy() from megasas_complete_command() to
megasas_unmap_frame(), so map/unmap are balanced.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180814141247.32336-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
Spotted by ASAN doing some manual testing:

Direct leak of 48 byte(s) in 1 object(s) allocated from:
    #0 0x7f5fcdc75e50 in calloc (/lib64/libasan.so.5+0xeee50)
    #1 0x7f5fcd47241d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5241d)
    #2 0x55f989be92ce in timer_new /home/elmarco/src/qq/include/qemu/timer.h:561
    #3 0x55f989be92ff in timer_new_ms /home/elmarco/src/qq/include/qemu/timer.h:630
    #4 0x55f989c0219d in hmp_migrate /home/elmarco/src/qq/hmp.c:2038
    #5 0x55f98955927b in handle_hmp_command /home/elmarco/src/qq/monitor.c:3498
    #6 0x55f98955fb8c in monitor_command_cb /home/elmarco/src/qq/monitor.c:4371
    #7 0x55f98ad40f11 in readline_handle_byte /home/elmarco/src/qq/util/readline.c:393
    #8 0x55f98955fa4f in monitor_read /home/elmarco/src/qq/monitor.c:4354
    #9 0x55f98aae30d7 in qemu_chr_be_write_impl /home/elmarco/src/qq/chardev/char.c:175
    #10 0x55f98aae317a in qemu_chr_be_write /home/elmarco/src/qq/chardev/char.c:187
    #11 0x55f98aae940c in fd_chr_read /home/elmarco/src/qq/chardev/char-fd.c:66
    #12 0x55f98ab63018 in qio_channel_fd_source_dispatch /home/elmarco/src/qq/io/channel-watch.c:84
    #13 0x7f5fcd46c8ac in g_main_dispatch gmain.c:3177

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180901134652.25884-1-marcandre.lureau@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
In qemu_laio_process_completions_and_submit, the AioContext is acquired
before the ioq_submit iteration and after qemu_laio_process_completions,
but the latter is not thread safe either.

This change avoids a number of random crashes when the Main Thread and
an IO Thread collide processing completions for the same AioContext.
This is an example of such crash:

 - The IO Thread is trying to acquire the AioContext at aio_co_enter,
   which evidences that it didn't lock it before:

Thread 3 (Thread 0x7fdfd8bd8700 (LWP 36743)):
 #0  0x00007fdfe0dd542d in __lll_lock_wait () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135
 #1  0x00007fdfe0dd0de6 in _L_lock_870 () at /lib64/libpthread.so.0
 #2  0x00007fdfe0dd0cdf in __GI___pthread_mutex_lock (mutex=mutex@entry=0x5631fde0e6c0)
    at ../nptl/pthread_mutex_lock.c:114
 #3  0x00005631fc0603a7 in qemu_mutex_lock_impl (mutex=0x5631fde0e6c0, file=0x5631fc23520f "util/async.c", line=511) at util/qemu-thread-posix.c:66
 #4  0x00005631fc05b558 in aio_co_enter (ctx=0x5631fde0e660, co=0x7fdfcc0c2b40) at util/async.c:493
 #5  0x00005631fc05b5ac in aio_co_wake (co=<optimized out>) at util/async.c:478
 #6  0x00005631fbfc51ad in qemu_laio_process_completion (laiocb=<optimized out>) at block/linux-aio.c:104
 #7  0x00005631fbfc523c in qemu_laio_process_completions (s=s@entry=0x7fdfc0297670)
    at block/linux-aio.c:222
 #8  0x00005631fbfc5499 in qemu_laio_process_completions_and_submit (s=0x7fdfc0297670)
    at block/linux-aio.c:237
 #9  0x00005631fc05d978 in aio_dispatch_handlers (ctx=ctx@entry=0x5631fde0e660) at util/aio-posix.c:406
 #10 0x00005631fc05e3ea in aio_poll (ctx=0x5631fde0e660, blocking=blocking@entry=true)
    at util/aio-posix.c:693
 #11 0x00005631fbd7ad96 in iothread_run (opaque=0x5631fde0e1c0) at iothread.c:64
 #12 0x00007fdfe0dcee25 in start_thread (arg=0x7fdfd8bd8700) at pthread_create.c:308
 #13 0x00007fdfe0afc34d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:113

 - The Main Thread is also processing completions from the same
   AioContext, and crashes due to failed assertion at util/iov.c:78:

Thread 1 (Thread 0x7fdfeb5eac80 (LWP 36740)):
 #0  0x00007fdfe0a391f7 in __GI_raise (sig=sig@entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
 #1  0x00007fdfe0a3a8e8 in __GI_abort () at abort.c:90
 #2  0x00007fdfe0a32266 in __assert_fail_base (fmt=0x7fdfe0b84e68 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x5631fc238ccb "offset == 0", file=file@entry=0x5631fc23698e "util/iov.c", line=line@entry=78, function=function@entry=0x5631fc236adc <__PRETTY_FUNCTION__.15220> "iov_memset")
    at assert.c:92
 #3  0x00007fdfe0a32312 in __GI___assert_fail (assertion=assertion@entry=0x5631fc238ccb "offset == 0", file=file@entry=0x5631fc23698e "util/iov.c", line=line@entry=78, function=function@entry=0x5631fc236adc <__PRETTY_FUNCTION__.15220> "iov_memset") at assert.c:101
 #4  0x00005631fc065287 in iov_memset (iov=<optimized out>, iov_cnt=<optimized out>, offset=<optimized out>, offset@entry=65536, fillc=fillc@entry=0, bytes=15515191315812405248) at util/iov.c:78
 #5  0x00005631fc065a63 in qemu_iovec_memset (qiov=<optimized out>, offset=offset@entry=65536, fillc=fillc@entry=0, bytes=<optimized out>) at util/iov.c:410
 #6  0x00005631fbfc5178 in qemu_laio_process_completion (laiocb=0x7fdd920df630) at block/linux-aio.c:88
 #7  0x00005631fbfc523c in qemu_laio_process_completions (s=s@entry=0x7fdfc0297670)
    at block/linux-aio.c:222
 #8  0x00005631fbfc5499 in qemu_laio_process_completions_and_submit (s=0x7fdfc0297670)
    at block/linux-aio.c:237
 #9  0x00005631fbfc54ed in qemu_laio_poll_cb (opaque=<optimized out>) at block/linux-aio.c:272
 #10 0x00005631fc05d85e in run_poll_handlers_once (ctx=ctx@entry=0x5631fde0e660) at util/aio-posix.c:497
 #11 0x00005631fc05e2ca in aio_poll (blocking=false, ctx=0x5631fde0e660) at util/aio-posix.c:574
 #12 0x00005631fc05e2ca in aio_poll (ctx=0x5631fde0e660, blocking=blocking@entry=false)
    at util/aio-posix.c:604
 #13 0x00005631fbfcb8a3 in bdrv_do_drained_begin (ignore_parent=<optimized out>, recursive=<optimized out>, bs=<optimized out>) at block/io.c:273
 #14 0x00005631fbfcb8a3 in bdrv_do_drained_begin (bs=0x5631fe8b6200, recursive=<optimized out>, parent=0x0, ignore_bds_parents=<optimized out>, poll=<optimized out>) at block/io.c:390
 #15 0x00005631fbfbcd2e in blk_drain (blk=0x5631fe83ac80) at block/block-backend.c:1590
 #16 0x00005631fbfbe138 in blk_remove_bs (blk=blk@entry=0x5631fe83ac80) at block/block-backend.c:774
 #17 0x00005631fbfbe3d6 in blk_unref (blk=0x5631fe83ac80) at block/block-backend.c:401
 #18 0x00005631fbfbe3d6 in blk_unref (blk=0x5631fe83ac80) at block/block-backend.c:449
 #19 0x00005631fbfc9a69 in commit_complete (job=0x5631fe8b94b0, opaque=0x7fdfcc1bb080)
    at block/commit.c:92
 #20 0x00005631fbf7d662 in job_defer_to_main_loop_bh (opaque=0x7fdfcc1b4560) at job.c:973
 #21 0x00005631fc05ad41 in aio_bh_poll (bh=0x7fdfcc01ad90) at util/async.c:90
 #22 0x00005631fc05ad41 in aio_bh_poll (ctx=ctx@entry=0x5631fddffdb0) at util/async.c:118
 #23 0x00005631fc05e210 in aio_dispatch (ctx=0x5631fddffdb0) at util/aio-posix.c:436
 #24 0x00005631fc05ac1e in aio_ctx_dispatch (source=<optimized out>, callback=<optimized out>, user_data=<optimized out>) at util/async.c:261
 #25 0x00007fdfeaae44c9 in g_main_context_dispatch (context=0x5631fde00140) at gmain.c:3201
 #26 0x00007fdfeaae44c9 in g_main_context_dispatch (context=context@entry=0x5631fde00140) at gmain.c:3854
 #27 0x00005631fc05d503 in main_loop_wait () at util/main-loop.c:215
 #28 0x00005631fc05d503 in main_loop_wait (timeout=<optimized out>) at util/main-loop.c:238
 #29 0x00005631fc05d503 in main_loop_wait (nonblocking=nonblocking@entry=0) at util/main-loop.c:497
 #30 0x00005631fbd81412 in main_loop () at vl.c:1866
 #31 0x00005631fbc18ff3 in main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>)
    at vl.c:4647

 - A closer examination shows that s->io_q.in_flight appears to have
   gone backwards:

(gdb) frame 7
 #7  0x00005631fbfc523c in qemu_laio_process_completions (s=s@entry=0x7fdfc0297670)
    at block/linux-aio.c:222
222	            qemu_laio_process_completion(laiocb);
(gdb) p s
$2 = (LinuxAioState *) 0x7fdfc0297670
(gdb) p *s
$3 = {aio_context = 0x5631fde0e660, ctx = 0x7fdfeb43b000, e = {rfd = 33, wfd = 33}, io_q = {plugged = 0,
    in_queue = 0, in_flight = 4294967280, blocked = false, pending = {sqh_first = 0x0,
      sqh_last = 0x7fdfc0297698}}, completion_bh = 0x7fdfc0280ef0, event_idx = 21, event_max = 241}
(gdb) p/x s->io_q.in_flight
$4 = 0xfffffff0

Signed-off-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
Spotted by ASAN while running:

$ tests/migration-test -p /x86_64/migration/postcopy/recovery

=================================================================
==18034==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 33864 byte(s) in 1 object(s) allocated from:
    #0 0x7f3da7f31e50 in calloc (/lib64/libasan.so.5+0xeee50)
    #1 0x7f3da644441d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5241d)
    #2 0x55af9db15440 in qemu_fopen_channel_input /home/elmarco/src/qemu/migration/qemu-file-channel.c:183
    #3 0x55af9db15413 in channel_get_output_return_path /home/elmarco/src/qemu/migration/qemu-file-channel.c:159
    #4 0x55af9db0d4ac in qemu_file_get_return_path /home/elmarco/src/qemu/migration/qemu-file.c:78
    #5 0x55af9dad5e4f in open_return_path_on_source /home/elmarco/src/qemu/migration/migration.c:2295
    #6 0x55af9dadb3bf in migrate_fd_connect /home/elmarco/src/qemu/migration/migration.c:3111
    #7 0x55af9dae1bf3 in migration_channel_connect /home/elmarco/src/qemu/migration/channel.c:91
    #8 0x55af9daddeca in socket_outgoing_migration /home/elmarco/src/qemu/migration/socket.c:108
    #9 0x55af9e13d3db in qio_task_complete /home/elmarco/src/qemu/io/task.c:158
    #10 0x55af9e13ca03 in qio_task_thread_result /home/elmarco/src/qemu/io/task.c:89
    #11 0x7f3da643b1ca in g_idle_dispatch gmain.c:5535

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180925092245.29565-1-marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
Recently, the test case has started failing because some job related
functions want to drop the AioContext lock even though it hasn't been
taken:

    (gdb) bt
    #0  0x00007f51c067c9fb in raise () from /lib64/libc.so.6
    #1  0x00007f51c067e77d in abort () from /lib64/libc.so.6
    #2  0x0000558c9d5dde7b in error_exit (err=<optimized out>, msg=msg@entry=0x558c9d6fe120 <__func__.18373> "qemu_mutex_unlock_impl") at util/qemu-thread-posix.c:36
    #3  0x0000558c9d6b5263 in qemu_mutex_unlock_impl (mutex=mutex@entry=0x558c9f3999a0, file=file@entry=0x558c9d6fd36f "util/async.c", line=line@entry=516) at util/qemu-thread-posix.c:96
    #4  0x0000558c9d6b0565 in aio_context_release (ctx=ctx@entry=0x558c9f399940) at util/async.c:516
    #5  0x0000558c9d5eb3da in job_completed_txn_abort (job=0x558c9f68e640) at job.c:738
    #6  0x0000558c9d5eb227 in job_finish_sync (job=0x558c9f68e640, finish=finish@entry=0x558c9d5eb8d0 <job_cancel_err>, errp=errp@entry=0x0) at job.c:986
    #7  0x0000558c9d5eb8ee in job_cancel_sync (job=<optimized out>) at job.c:941
    #8  0x0000558c9d64d853 in replication_close (bs=<optimized out>) at block/replication.c:148
    #9  0x0000558c9d5e5c9f in bdrv_close (bs=0x558c9f41b020) at block.c:3420
    #10 bdrv_delete (bs=0x558c9f41b020) at block.c:3629
    #11 bdrv_unref (bs=0x558c9f41b020) at block.c:4685
    #12 0x0000558c9d62a3f3 in blk_remove_bs (blk=blk@entry=0x558c9f42a7c0) at block/block-backend.c:783
    #13 0x0000558c9d62a667 in blk_delete (blk=0x558c9f42a7c0) at block/block-backend.c:402
    #14 blk_unref (blk=0x558c9f42a7c0) at block/block-backend.c:457
    #15 0x0000558c9d5dfcea in test_secondary_stop () at tests/test-replication.c:478
    #16 0x00007f51c1f13178 in g_test_run_suite_internal () from /lib64/libglib-2.0.so.0
    #17 0x00007f51c1f1337b in g_test_run_suite_internal () from /lib64/libglib-2.0.so.0
    #18 0x00007f51c1f1337b in g_test_run_suite_internal () from /lib64/libglib-2.0.so.0
    #19 0x00007f51c1f13552 in g_test_run_suite () from /lib64/libglib-2.0.so.0
    #20 0x00007f51c1f13571 in g_test_run () from /lib64/libglib-2.0.so.0
    #21 0x0000558c9d5de31f in main (argc=<optimized out>, argv=<optimized out>) at tests/test-replication.c:581

It is yet unclear whether this should really be considered a bug in the
test case or whether blk_unref() should work for callers that haven't
taken the AioContext lock, but in order to fix the build tests quickly,
just take the AioContext lock around blk_unref().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
amboar pushed a commit that referenced this issue Oct 23, 2018
Spotted by ASAN:
=================================================================
==11893==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 1120 byte(s) in 28 object(s) allocated from:
    #0 0x7fd0515b0c48 in malloc (/lib64/libasan.so.5+0xeec48)
    #1 0x7fd050ffa3c5 in g_malloc (/lib64/libglib-2.0.so.0+0x523c5)
    #2 0x559e708b56a4 in qstring_from_str /home/elmarco/src/qq/qobject/qstring.c:66
    #3 0x559e708b4fe0 in qstring_new /home/elmarco/src/qq/qobject/qstring.c:23
    #4 0x559e708bda7d in parse_string /home/elmarco/src/qq/qobject/json-parser.c:143
    #5 0x559e708c1009 in parse_literal /home/elmarco/src/qq/qobject/json-parser.c:484
    #6 0x559e708c1627 in parse_value /home/elmarco/src/qq/qobject/json-parser.c:547
    #7 0x559e708c1c67 in json_parser_parse /home/elmarco/src/qq/qobject/json-parser.c:573
    #8 0x559e708bc0ff in json_message_process_token /home/elmarco/src/qq/qobject/json-streamer.c:92
    #9 0x559e708d1655 in json_lexer_feed_char /home/elmarco/src/qq/qobject/json-lexer.c:292
    #10 0x559e708d1fe1 in json_lexer_feed /home/elmarco/src/qq/qobject/json-lexer.c:339
    #11 0x559e708bc856 in json_message_parser_feed /home/elmarco/src/qq/qobject/json-streamer.c:121
    #12 0x559e708b8b4b in qobject_from_jsonv /home/elmarco/src/qq/qobject/qjson.c:69
    #13 0x559e708b8d02 in qobject_from_json /home/elmarco/src/qq/qobject/qjson.c:83
    #14 0x559e708a74ae in from_json_str /home/elmarco/src/qq/tests/check-qjson.c:30
    #15 0x559e708a9f83 in utf8_string /home/elmarco/src/qq/tests/check-qjson.c:781
    #16 0x7fd05101bc49 in test_case_run gtestutils.c:2255
    #17 0x7fd05101bc49 in g_test_run_suite_internal gtestutils.c:2339

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180901211917.10372-1-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
amboar pushed a commit that referenced this issue Jan 14, 2019
Let start from the beginning:

Commit b9e413d (in 2.9)
"block: explicitly acquire aiocontext in aio callbacks that need it"
added pairs of aio_context_acquire/release to mirror_write_complete and
mirror_read_complete, when they were aio callbacks for blk_aio_* calls.

Then, commit 2e1990b (in 3.0) "block/mirror: Convert to coroutines"
dropped these blk_aio_* calls, than mirror_write_complete and
mirror_read_complete are not callbacks more, and don't need additional
aiocontext acquiring. Furthermore, mirror_read_complete calls
blk_co_pwritev inside these pair of aio_context_acquire/release, which
leads to the following dead-lock with mirror:

 (gdb) info thr
   Id   Target Id         Frame
   3    Thread (LWP 145412) "qemu-system-x86" syscall ()
   2    Thread (LWP 145416) "qemu-system-x86" __lll_lock_wait ()
 * 1    Thread (LWP 145411) "qemu-system-x86" __lll_lock_wait ()

 (gdb) bt
 #0  __lll_lock_wait ()
 #1  _L_lock_812 ()
 #2  __GI___pthread_mutex_lock
 #3  qemu_mutex_lock_impl (mutex=0x561032dce420 <qemu_global_mutex>,
     file=0x5610327d8654 "util/main-loop.c", line=236) at
     util/qemu-thread-posix.c:66
 #4  qemu_mutex_lock_iothread_impl
 #5  os_host_main_loop_wait (timeout=480116000) at util/main-loop.c:236
 #6  main_loop_wait (nonblocking=0) at util/main-loop.c:497
 #7  main_loop () at vl.c:1892
 #8  main

Printing contents of qemu_global_mutex, I see that "__owner = 145416",
so, thr1 is main loop, and now it wants BQL, which is owned by thr2.

 (gdb) thr 2
 (gdb) bt
 #0  __lll_lock_wait ()
 #1  _L_lock_870 ()
 #2  __GI___pthread_mutex_lock
 #3  qemu_mutex_lock_impl (mutex=0x561034d25dc0, ...
 #4  aio_context_acquire (ctx=0x561034d25d60)
 #5  dma_blk_cb
 #6  dma_blk_io
 #7  dma_blk_read
 #8  ide_dma_cb
 #9  bmdma_cmd_writeb
 #10 bmdma_write
 #11 memory_region_write_accessor
 #12 access_with_adjusted_size
 #15 flatview_write
 #16 address_space_write
 #17 address_space_rw
 #18 kvm_handle_io
 #19 kvm_cpu_exec
 #20 qemu_kvm_cpu_thread_fn
 #21 qemu_thread_start
 #22 start_thread
 #23 clone ()

Printing mutex in fr 2, I see "__owner = 145411", so thr2 wants aio
context mutex, which is owned by thr1. Classic dead-lock.

Then, let's check that aio context is hold by mirror coroutine: just
print coroutine stack of first tracked request in mirror job target:

 (gdb) [...]
 (gdb) qemu coroutine 0x561035dd0860
 #0  qemu_coroutine_switch
 #1  qemu_coroutine_yield
 #2  qemu_co_mutex_lock_slowpath
 #3  qemu_co_mutex_lock
 #4  qcow2_co_pwritev
 #5  bdrv_driver_pwritev
 #6  bdrv_aligned_pwritev
 #7  bdrv_co_pwritev
 #8  blk_co_pwritev
 #9  mirror_read_complete () at block/mirror.c:232
 #10 mirror_co_read () at block/mirror.c:370
 #11 coroutine_trampoline
 #12 __start_context

Yes it is mirror_read_complete calling blk_co_pwritev after acquiring
aio context.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
amboar pushed a commit that referenced this issue Oct 21, 2024
Allow overlapping request by removing the assert that made it
impossible. There are only two callers:

1. block_copy_task_create()

It already asserts the very same condition before calling
reqlist_init_req().

2. cbw_snapshot_read_lock()

There is no need to have read requests be non-overlapping in
copy-before-write when used for snapshot-access. In fact, there was no
protection against two callers of cbw_snapshot_read_lock() calling
reqlist_init_req() with overlapping ranges and this could lead to an
assertion failure [1].

In particular, with the reproducer script below [0], two
cbw_co_snapshot_block_status() callers could race, with the second
calling reqlist_init_req() before the first one finishes and removes
its conflicting request.

[0]:

> #!/bin/bash -e
> dd if=/dev/urandom of=/tmp/disk.raw bs=1M count=1024
> ./qemu-img create /tmp/fleecing.raw -f raw 1G
> (
> ./qemu-system-x86_64 --qmp stdio \
> --blockdev raw,node-name=node0,file.driver=file,file.filename=/tmp/disk.raw \
> --blockdev raw,node-name=node1,file.driver=file,file.filename=/tmp/fleecing.raw \
> <<EOF
> {"execute": "qmp_capabilities"}
> {"execute": "blockdev-add", "arguments": { "driver": "copy-before-write", "file": "node0", "target": "node1", "node-name": "node3" } }
> {"execute": "blockdev-add", "arguments": { "driver": "snapshot-access", "file": "node3", "node-name": "snap0" } }
> {"execute": "nbd-server-start", "arguments": {"addr": { "type": "unix", "data": { "path": "/tmp/nbd.socket" } } } }
> {"execute": "block-export-add", "arguments": {"id": "exp0", "node-name": "snap0", "type": "nbd", "name": "exp0"}}
> EOF
> ) &
> sleep 5
> while true; do
> ./qemu-nbd -d /dev/nbd0
> ./qemu-nbd -c /dev/nbd0 nbd:unix:/tmp/nbd.socket:exportname=exp0 -f raw -r
> nbdinfo --map 'nbd+unix:///exp0?socket=/tmp/nbd.socket'
> done

[1]:

> #5  0x000071e5f0088eb2 in __GI___assert_fail (...) at ./assert/assert.c:101
> #6  0x0000615285438017 in reqlist_init_req (...) at ../block/reqlist.c:23
> #7  0x00006152853e2d98 in cbw_snapshot_read_lock (...) at ../block/copy-before-write.c:237
> #8  0x00006152853e3068 in cbw_co_snapshot_block_status (...) at ../block/copy-before-write.c:304
> #9  0x00006152853f4d22 in bdrv_co_snapshot_block_status (...) at ../block/io.c:3726
> #10 0x000061528543a63e in snapshot_access_co_block_status (...) at ../block/snapshot-access.c:48
> #11 0x00006152853f1a0a in bdrv_co_do_block_status (...) at ../block/io.c:2474
> #12 0x00006152853f2016 in bdrv_co_common_block_status_above (...) at ../block/io.c:2652
> #13 0x00006152853f22cf in bdrv_co_block_status_above (...) at ../block/io.c:2732
> #14 0x00006152853d9a86 in blk_co_block_status_above (...) at ../block/block-backend.c:1473
> #15 0x000061528538da6c in blockstatus_to_extents (...) at ../nbd/server.c:2374
> #16 0x000061528538deb1 in nbd_co_send_block_status (...) at ../nbd/server.c:2481
> #17 0x000061528538f424 in nbd_handle_request (...) at ../nbd/server.c:2978
> #18 0x000061528538f906 in nbd_trip (...) at ../nbd/server.c:3121
> #19 0x00006152855a7caf in coroutine_trampoline (...) at ../util/coroutine-ucontext.c:175

Cc: qemu-stable@nongnu.org
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-Id: <20240712140716.517911-1-f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
(cherry picked from commit 6475155)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
amboar pushed a commit that referenced this issue Nov 20, 2024
In regime_is_user() we assert if we're passed an ARMMMUIdx_E10_*
mmuidx value. This used to make sense because we only used this
function in ptw.c and would never use it on this kind of stage 1+2
mmuidx, only for an individual stage 1 or stage 2 mmuidx.

However, when we implemented FEAT_E0PD we added a callsite in
aa64_va_parameters(), which means this can now be called for
stage 1+2 mmuidx values if the guest sets the TCG_ELX.{E0PD0,E0PD1}
bits to enable use of the feature. This will then result in
an assertion failure later, for instance on a TLBI operation:

#6  0x00007ffff6d0e70f in g_assertion_message_expr
    (domain=0x0, file=0x55555676eeba "../../target/arm/internals.h", line=978, func=0x555556771d48 <__func__.5> "regime_is_user", expr=<optimised out>)
    at ../../../glib/gtestutils.c:3279
#7  0x0000555555f286d2 in regime_is_user (env=0x555557f2fe00, mmu_idx=ARMMMUIdx_E10_0) at ../../target/arm/internals.h:978
#8  0x0000555555f3e31c in aa64_va_parameters (env=0x555557f2fe00, va=18446744073709551615, mmu_idx=ARMMMUIdx_E10_0, data=true, el1_is_aa32=false)
    at ../../target/arm/helper.c:12048
#9  0x0000555555f3163b in tlbi_aa64_get_range (env=0x555557f2fe00, mmuidx=ARMMMUIdx_E10_0, value=106721347371041) at ../../target/arm/helper.c:5214
#10 0x0000555555f317e8 in do_rvae_write (env=0x555557f2fe00, value=106721347371041, idxmap=21, synced=true) at ../../target/arm/helper.c:5260
#11 0x0000555555f31925 in tlbi_aa64_rvae1is_write (env=0x555557f2fe00, ri=0x555557fbeae0, value=106721347371041) at ../../target/arm/helper.c:5302
#12 0x0000555556036f8f in helper_set_cp_reg64 (env=0x555557f2fe00, rip=0x555557fbeae0, value=106721347371041) at ../../target/arm/tcg/op_helper.c:965

Since we do know whether these mmuidx values are for usermode
or not, we can easily make regime_is_user() handle them:
ARMMMUIdx_E10_0 is user, and the other two are not.

Cc: qemu-stable@nongnu.org
Fixes: e4c93e4 ("target/arm: Implement FEAT_E0PD")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20241017172331.822587-1-peter.maydell@linaro.org
(cherry picked from commit 1505b65)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
amboar pushed a commit that referenced this issue Nov 20, 2024
qemu-ga on a NetBSD -current VM terminates with a SIGSEGV upon receiving
'guest-set-time' command...

Core was generated by `qemu-ga'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x000000000cd37a40 in ga_pipe_read_str (fd=fd@entry=0xffffff922a20, str=str@entry=0xffffff922a18)
    at ../qga/commands-posix.c:88
88	        *str[len] = '\0';
[Current thread is 1 (process 1112)]
(gdb) bt
#0  0x000000000cd37a40 in ga_pipe_read_str (fd=fd@entry=0xffffff922a20, str=str@entry=0xffffff922a18)
    at ../qga/commands-posix.c:88
#1  0x000000000cd37b60 in ga_run_command (argv=argv@entry=0xffffff922a90,
    action=action@entry=0xcda34b8 "set hardware clock to system time", errp=errp@entry=0xffffff922a70, in_str=0x0)
    at ../qga/commands-posix.c:164
#2  0x000000000cd380c4 in qmp_guest_set_time (has_time=<optimized out>, time_ns=<optimized out>,
    errp=errp@entry=0xffffff922ad0) at ../qga/commands-posix.c:304
#3  0x000000000cd253d8 in qmp_marshal_guest_set_time (args=<optimized out>, ret=<optimized out>, errp=0xffffff922b48)
    at qga/qga-qapi-commands.c:193
#4  0x000000000cd4e71c in qmp_dispatch (cmds=cmds@entry=0xcdf5b18 <ga_commands>, request=request@entry=0xf3c711a4b000,
    allow_oob=allow_oob@entry=false, cur_mon=cur_mon@entry=0x0) at ../qapi/qmp-dispatch.c:220
#5  0x000000000cd36524 in process_event (opaque=0xf3c711a79000, obj=0xf3c711a4b000, err=0x0) at ../qga/main.c:677
#6  0x000000000cd526f0 in json_message_process_token (lexer=lexer@entry=0xf3c711a79018, input=0xf3c712072480,
    type=type@entry=JSON_RCURLY, x=28, y=1) at ../qobject/json-streamer.c:99
#7  0x000000000cd93860 in json_lexer_feed_char (lexer=lexer@entry=0xf3c711a79018, ch=125 '}', flush=flush@entry=false)
    at ../qobject/json-lexer.c:313
#8  0x000000000cd93a00 in json_lexer_feed (lexer=lexer@entry=0xf3c711a79018,
    buffer=buffer@entry=0xffffff922d10 "{\"execute\":\"guest-set-time\"}\n", size=<optimized out>)
    at ../qobject/json-lexer.c:350
#9  0x000000000cd5290c in json_message_parser_feed (parser=parser@entry=0xf3c711a79000,
    buffer=buffer@entry=0xffffff922d10 "{\"execute\":\"guest-set-time\"}\n", size=<optimized out>)
    at ../qobject/json-streamer.c:121
#10 0x000000000cd361fc in channel_event_cb (condition=<optimized out>, data=0xf3c711a79000) at ../qga/main.c:703
#11 0x000000000cd3710c in ga_channel_client_event (channel=<optimized out>, condition=<optimized out>, data=0xf3c711b2d300)
    at ../qga/channel-posix.c:94
#12 0x0000f3c7120d9bec in g_main_dispatch () from /usr/pkg/lib/libglib-2.0.so.0
#13 0x0000f3c7120dd25c in g_main_context_iterate_unlocked.constprop () from /usr/pkg/lib/libglib-2.0.so.0
#14 0x0000f3c7120ddbf0 in g_main_loop_run () from /usr/pkg/lib/libglib-2.0.so.0
#15 0x000000000cda00d8 in run_agent_once (s=0xf3c711a79000) at ../qga/main.c:1522
#16 run_agent (s=0xf3c711a79000) at ../qga/main.c:1559
#17 main (argc=<optimized out>, argv=<optimized out>) at ../qga/main.c:1671
(gdb)

The commandline options used on the host machine...
qemu-system-aarch64 \
   -machine type=virt,pflash0=rom \
   -m 8G \
   -cpu host \
   -smp 8 \
   -accel hvf \
   -device virtio-net-pci,netdev=unet \
   -device virtio-blk-pci,drive=hd \
   -drive file=netbsd.qcow2,if=none,id=hd \
   -netdev user,id=unet,hostfwd=tcp::2223-:22 \
   -object rng-random,filename=/dev/urandom,id=viornd0 \
   -device virtio-rng-pci,rng=viornd0 \
   -serial mon:stdio \
   -display none \
   -blockdev node-name=rom,driver=file,filename=/opt/homebrew/Cellar/qemu/9.0.2/share/qemu/edk2-aarch64-code.fd,read-only=true \
   -chardev socket,path=/tmp/qga_netbsd.sock,server=on,wait=off,id=qga0 \
   -device virtio-serial \
   -device virtconsole,chardev=qga0,name=org.qemu.guest_agent.0

This patch rectifies the operator precedence while assigning the NUL
terminator.

Fixes: c3f32c1

Signed-off-by: Sunil Nimmagadda <sunil@nimmagadda.net>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Link: https://lore.kernel.org/r/m15xppk9qg.fsf@nimmagadda.net
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>
(cherry picked from commit 9cfe110)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
amboar pushed a commit that referenced this issue Dec 11, 2024
…et_end()

In multifd_mapped_ram_fdset_end() we call qtest_qmp() but forgot
to unref the response QDict we get back, which means it is leaked:

Indirect leak of 4120 byte(s) in 1 object(s) allocated from:
    #0 0x55c0c095d318 in __interceptor_calloc (/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/asan/tests/qtest/migration-test+0x22f318) (BuildI
d: 07f667506452d6c467dbc06fd95191966d3e91b4)
    #1 0x7f186f939c50 in g_malloc0 debian/build/deb/../../../glib/gmem.c:161:13
    #2 0x55c0c0ae9b01 in qdict_new qobject/qdict.c:30:13
    #3 0x55c0c0afc16c in parse_object qobject/json-parser.c:317:12
    #4 0x55c0c0afb90f in parse_value qobject/json-parser.c:545:16
    #5 0x55c0c0afb579 in json_parser_parse qobject/json-parser.c:579:14
    #6 0x55c0c0afa21d in json_message_process_token qobject/json-streamer.c:92:12
    #7 0x55c0c0bca2e5 in json_lexer_feed_char qobject/json-lexer.c:313:13
    #8 0x55c0c0bc97ce in json_lexer_feed qobject/json-lexer.c:350:9
    #9 0x55c0c0afabbc in json_message_parser_feed qobject/json-streamer.c:121:5
    #10 0x55c0c09cbd52 in qmp_fd_receive tests/qtest/libqmp.c:86:9
    #11 0x55c0c09be69b in qtest_qmp_receive_dict tests/qtest/libqtest.c:760:12
    #12 0x55c0c09bca77 in qtest_qmp_receive tests/qtest/libqtest.c:741:27
    #13 0x55c0c09bee9d in qtest_vqmp tests/qtest/libqtest.c:812:12
    #14 0x55c0c09bd257 in qtest_qmp tests/qtest/libqtest.c:835:16
    #15 0x55c0c0a87747 in multifd_mapped_ram_fdset_end tests/qtest/migration-test.c:2393:12
    #16 0x55c0c0a85eb3 in test_file_common tests/qtest/migration-test.c:1978:9
    #17 0x55c0c0a746a3 in test_multifd_file_mapped_ram_fdset tests/qtest/migration-test.c:2437:5
    #18 0x55c0c0a93237 in migration_test_wrapper tests/qtest/migration-helpers.c:458:5
    #19 0x7f186f958aed in test_case_run debian/build/deb/../../../glib/gtestutils.c:2930:15
    #20 0x7f186f958aed in g_test_run_suite_internal debian/build/deb/../../../glib/gtestutils.c:3018:16
    #21 0x7f186f95880a in g_test_run_suite_internal debian/build/deb/../../../glib/gtestutils.c:3035:18
    #22 0x7f186f95880a in g_test_run_suite_internal debian/build/deb/../../../glib/gtestutils.c:3035:18
    #23 0x7f186f95880a in g_test_run_suite_internal debian/build/deb/../../../glib/gtestutils.c:3035:18
    #24 0x7f186f95880a in g_test_run_suite_internal debian/build/deb/../../../glib/gtestutils.c:3035:18
    #25 0x7f186f95880a in g_test_run_suite_internal debian/build/deb/../../../glib/gtestutils.c:3035:18
    #26 0x7f186f958faa in g_test_run_suite debian/build/deb/../../../glib/gtestutils.c:3109:18
    #27 0x7f186f959055 in g_test_run debian/build/deb/../../../glib/gtestutils.c:2231:7
    #28 0x7f186f959055 in g_test_run debian/build/deb/../../../glib/gtestutils.c:2218:1
    #29 0x55c0c0a6e427 in main tests/qtest/migration-test.c:4033:11

Unref the object after we've confirmed that it is what we expect.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
amboar pushed a commit that referenced this issue Dec 11, 2024
We create a gnutls_x509_privkey_t in test_tls_init(), but forget
to deinit it in test_tls_cleanup(), resulting in leaks
reported in hte migration test such as:

Indirect leak of 8 byte(s) in 1 object(s) allocated from:
    #0 0x55fa6d11c12e in malloc (/mnt/nvmedisk/linaro/qemu-from-laptop/qemu/build/asan/tests/qtest/migration-test+0x22f12e) (BuildId: 852a267993587f557f50e5715f352f43720077ba)
    #1 0x7f073982685d in __gmp_default_allocate (/lib/x86_64-linux-gnu/libgmp.so.10+0xa85d) (BuildId: f110719303ddbea25a5e89ff730fec520eed67b0)
    #2 0x7f0739836193 in __gmpz_realloc (/lib/x86_64-linux-gnu/libgmp.so.10+0x1a193) (BuildId: f110719303ddbea25a5e89ff730fec520eed67b0)
    #3 0x7f0739836594 in __gmpz_import (/lib/x86_64-linux-gnu/libgmp.so.10+0x1a594) (BuildId: f110719303ddbea25a5e89ff730fec520eed67b0)
    #4 0x7f07398a91ed in nettle_mpz_set_str_256_u (/lib/x86_64-linux-gnu/libhogweed.so.6+0xb1ed) (BuildId: 3cc4a3474de72db89e9dcc93bfb95fe377f48c37)
    #5 0x7f073a146a5a  (/lib/x86_64-linux-gnu/libgnutls.so.30+0x131a5a) (BuildId: 97b8f99f392f1fd37b969a7164bcea884e23649b)
    #6 0x7f073a07192c  (/lib/x86_64-linux-gnu/libgnutls.so.30+0x5c92c) (BuildId: 97b8f99f392f1fd37b969a7164bcea884e23649b)
    #7 0x7f073a078333  (/lib/x86_64-linux-gnu/libgnutls.so.30+0x63333) (BuildId: 97b8f99f392f1fd37b969a7164bcea884e23649b)
    #8 0x7f073a0e8353  (/lib/x86_64-linux-gnu/libgnutls.so.30+0xd3353) (BuildId: 97b8f99f392f1fd37b969a7164bcea884e23649b)
    #9 0x7f073a0ef0ac in gnutls_x509_privkey_import (/lib/x86_64-linux-gnu/libgnutls.so.30+0xda0ac) (BuildId: 97b8f99f392f1fd37b969a7164bcea884e23649b)
    #10 0x55fa6d2547e3 in test_tls_load_key tests/unit/crypto-tls-x509-helpers.c:99:11
    #11 0x55fa6d25460c in test_tls_init tests/unit/crypto-tls-x509-helpers.c:128:15
    #12 0x55fa6d2495c4 in test_migrate_tls_x509_start_common tests/qtest/migration-test.c:1044:5
    #13 0x55fa6d24c23a in test_migrate_tls_x509_start_reject_anon_client tests/qtest/migration-test.c:1216:12
    #14 0x55fa6d23fb40 in test_precopy_common tests/qtest/migration-test.c:1789:21
    #15 0x55fa6d236b7c in test_precopy_tcp_tls_x509_reject_anon_client tests/qtest/migration-test.c:2614:5

(Oddly, there is no reported leak in the x509 unit tests, even though
those also use test_tls_init() and test_tls_cleanup().)

Deinit the privkey in test_tls_cleanup().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
amboar pushed a commit that referenced this issue Dec 11, 2024
Allow overlapping request by removing the assert that made it
impossible. There are only two callers:

1. block_copy_task_create()

It already asserts the very same condition before calling
reqlist_init_req().

2. cbw_snapshot_read_lock()

There is no need to have read requests be non-overlapping in
copy-before-write when used for snapshot-access. In fact, there was no
protection against two callers of cbw_snapshot_read_lock() calling
reqlist_init_req() with overlapping ranges and this could lead to an
assertion failure [1].

In particular, with the reproducer script below [0], two
cbw_co_snapshot_block_status() callers could race, with the second
calling reqlist_init_req() before the first one finishes and removes
its conflicting request.

[0]:

> #!/bin/bash -e
> dd if=/dev/urandom of=/tmp/disk.raw bs=1M count=1024
> ./qemu-img create /tmp/fleecing.raw -f raw 1G
> (
> ./qemu-system-x86_64 --qmp stdio \
> --blockdev raw,node-name=node0,file.driver=file,file.filename=/tmp/disk.raw \
> --blockdev raw,node-name=node1,file.driver=file,file.filename=/tmp/fleecing.raw \
> <<EOF
> {"execute": "qmp_capabilities"}
> {"execute": "blockdev-add", "arguments": { "driver": "copy-before-write", "file": "node0", "target": "node1", "node-name": "node3" } }
> {"execute": "blockdev-add", "arguments": { "driver": "snapshot-access", "file": "node3", "node-name": "snap0" } }
> {"execute": "nbd-server-start", "arguments": {"addr": { "type": "unix", "data": { "path": "/tmp/nbd.socket" } } } }
> {"execute": "block-export-add", "arguments": {"id": "exp0", "node-name": "snap0", "type": "nbd", "name": "exp0"}}
> EOF
> ) &
> sleep 5
> while true; do
> ./qemu-nbd -d /dev/nbd0
> ./qemu-nbd -c /dev/nbd0 nbd:unix:/tmp/nbd.socket:exportname=exp0 -f raw -r
> nbdinfo --map 'nbd+unix:///exp0?socket=/tmp/nbd.socket'
> done

[1]:

> #5  0x000071e5f0088eb2 in __GI___assert_fail (...) at ./assert/assert.c:101
> #6  0x0000615285438017 in reqlist_init_req (...) at ../block/reqlist.c:23
> #7  0x00006152853e2d98 in cbw_snapshot_read_lock (...) at ../block/copy-before-write.c:237
> #8  0x00006152853e3068 in cbw_co_snapshot_block_status (...) at ../block/copy-before-write.c:304
> #9  0x00006152853f4d22 in bdrv_co_snapshot_block_status (...) at ../block/io.c:3726
> #10 0x000061528543a63e in snapshot_access_co_block_status (...) at ../block/snapshot-access.c:48
> #11 0x00006152853f1a0a in bdrv_co_do_block_status (...) at ../block/io.c:2474
> #12 0x00006152853f2016 in bdrv_co_common_block_status_above (...) at ../block/io.c:2652
> #13 0x00006152853f22cf in bdrv_co_block_status_above (...) at ../block/io.c:2732
> #14 0x00006152853d9a86 in blk_co_block_status_above (...) at ../block/block-backend.c:1473
> #15 0x000061528538da6c in blockstatus_to_extents (...) at ../nbd/server.c:2374
> #16 0x000061528538deb1 in nbd_co_send_block_status (...) at ../nbd/server.c:2481
> #17 0x000061528538f424 in nbd_handle_request (...) at ../nbd/server.c:2978
> #18 0x000061528538f906 in nbd_trip (...) at ../nbd/server.c:3121
> #19 0x00006152855a7caf in coroutine_trampoline (...) at ../util/coroutine-ucontext.c:175

Cc: qemu-stable@nongnu.org
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-Id: <20240712140716.517911-1-f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
amboar pushed a commit that referenced this issue Dec 11, 2024
In regime_is_user() we assert if we're passed an ARMMMUIdx_E10_*
mmuidx value. This used to make sense because we only used this
function in ptw.c and would never use it on this kind of stage 1+2
mmuidx, only for an individual stage 1 or stage 2 mmuidx.

However, when we implemented FEAT_E0PD we added a callsite in
aa64_va_parameters(), which means this can now be called for
stage 1+2 mmuidx values if the guest sets the TCG_ELX.{E0PD0,E0PD1}
bits to enable use of the feature. This will then result in
an assertion failure later, for instance on a TLBI operation:

#6  0x00007ffff6d0e70f in g_assertion_message_expr
    (domain=0x0, file=0x55555676eeba "../../target/arm/internals.h", line=978, func=0x555556771d48 <__func__.5> "regime_is_user", expr=<optimised out>)
    at ../../../glib/gtestutils.c:3279
#7  0x0000555555f286d2 in regime_is_user (env=0x555557f2fe00, mmu_idx=ARMMMUIdx_E10_0) at ../../target/arm/internals.h:978
#8  0x0000555555f3e31c in aa64_va_parameters (env=0x555557f2fe00, va=18446744073709551615, mmu_idx=ARMMMUIdx_E10_0, data=true, el1_is_aa32=false)
    at ../../target/arm/helper.c:12048
#9  0x0000555555f3163b in tlbi_aa64_get_range (env=0x555557f2fe00, mmuidx=ARMMMUIdx_E10_0, value=106721347371041) at ../../target/arm/helper.c:5214
#10 0x0000555555f317e8 in do_rvae_write (env=0x555557f2fe00, value=106721347371041, idxmap=21, synced=true) at ../../target/arm/helper.c:5260
#11 0x0000555555f31925 in tlbi_aa64_rvae1is_write (env=0x555557f2fe00, ri=0x555557fbeae0, value=106721347371041) at ../../target/arm/helper.c:5302
#12 0x0000555556036f8f in helper_set_cp_reg64 (env=0x555557f2fe00, rip=0x555557fbeae0, value=106721347371041) at ../../target/arm/tcg/op_helper.c:965

Since we do know whether these mmuidx values are for usermode
or not, we can easily make regime_is_user() handle them:
ARMMMUIdx_E10_0 is user, and the other two are not.

Cc: qemu-stable@nongnu.org
Fixes: e4c93e4 ("target/arm: Implement FEAT_E0PD")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20241017172331.822587-1-peter.maydell@linaro.org
amboar pushed a commit that referenced this issue Dec 11, 2024
qemu-ga on a NetBSD -current VM terminates with a SIGSEGV upon receiving
'guest-set-time' command...

Core was generated by `qemu-ga'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x000000000cd37a40 in ga_pipe_read_str (fd=fd@entry=0xffffff922a20, str=str@entry=0xffffff922a18)
    at ../qga/commands-posix.c:88
88	        *str[len] = '\0';
[Current thread is 1 (process 1112)]
(gdb) bt
#0  0x000000000cd37a40 in ga_pipe_read_str (fd=fd@entry=0xffffff922a20, str=str@entry=0xffffff922a18)
    at ../qga/commands-posix.c:88
#1  0x000000000cd37b60 in ga_run_command (argv=argv@entry=0xffffff922a90,
    action=action@entry=0xcda34b8 "set hardware clock to system time", errp=errp@entry=0xffffff922a70, in_str=0x0)
    at ../qga/commands-posix.c:164
#2  0x000000000cd380c4 in qmp_guest_set_time (has_time=<optimized out>, time_ns=<optimized out>,
    errp=errp@entry=0xffffff922ad0) at ../qga/commands-posix.c:304
#3  0x000000000cd253d8 in qmp_marshal_guest_set_time (args=<optimized out>, ret=<optimized out>, errp=0xffffff922b48)
    at qga/qga-qapi-commands.c:193
#4  0x000000000cd4e71c in qmp_dispatch (cmds=cmds@entry=0xcdf5b18 <ga_commands>, request=request@entry=0xf3c711a4b000,
    allow_oob=allow_oob@entry=false, cur_mon=cur_mon@entry=0x0) at ../qapi/qmp-dispatch.c:220
#5  0x000000000cd36524 in process_event (opaque=0xf3c711a79000, obj=0xf3c711a4b000, err=0x0) at ../qga/main.c:677
#6  0x000000000cd526f0 in json_message_process_token (lexer=lexer@entry=0xf3c711a79018, input=0xf3c712072480,
    type=type@entry=JSON_RCURLY, x=28, y=1) at ../qobject/json-streamer.c:99
#7  0x000000000cd93860 in json_lexer_feed_char (lexer=lexer@entry=0xf3c711a79018, ch=125 '}', flush=flush@entry=false)
    at ../qobject/json-lexer.c:313
#8  0x000000000cd93a00 in json_lexer_feed (lexer=lexer@entry=0xf3c711a79018,
    buffer=buffer@entry=0xffffff922d10 "{\"execute\":\"guest-set-time\"}\n", size=<optimized out>)
    at ../qobject/json-lexer.c:350
#9  0x000000000cd5290c in json_message_parser_feed (parser=parser@entry=0xf3c711a79000,
    buffer=buffer@entry=0xffffff922d10 "{\"execute\":\"guest-set-time\"}\n", size=<optimized out>)
    at ../qobject/json-streamer.c:121
#10 0x000000000cd361fc in channel_event_cb (condition=<optimized out>, data=0xf3c711a79000) at ../qga/main.c:703
#11 0x000000000cd3710c in ga_channel_client_event (channel=<optimized out>, condition=<optimized out>, data=0xf3c711b2d300)
    at ../qga/channel-posix.c:94
#12 0x0000f3c7120d9bec in g_main_dispatch () from /usr/pkg/lib/libglib-2.0.so.0
#13 0x0000f3c7120dd25c in g_main_context_iterate_unlocked.constprop () from /usr/pkg/lib/libglib-2.0.so.0
#14 0x0000f3c7120ddbf0 in g_main_loop_run () from /usr/pkg/lib/libglib-2.0.so.0
#15 0x000000000cda00d8 in run_agent_once (s=0xf3c711a79000) at ../qga/main.c:1522
#16 run_agent (s=0xf3c711a79000) at ../qga/main.c:1559
#17 main (argc=<optimized out>, argv=<optimized out>) at ../qga/main.c:1671
(gdb)

The commandline options used on the host machine...
qemu-system-aarch64 \
   -machine type=virt,pflash0=rom \
   -m 8G \
   -cpu host \
   -smp 8 \
   -accel hvf \
   -device virtio-net-pci,netdev=unet \
   -device virtio-blk-pci,drive=hd \
   -drive file=netbsd.qcow2,if=none,id=hd \
   -netdev user,id=unet,hostfwd=tcp::2223-:22 \
   -object rng-random,filename=/dev/urandom,id=viornd0 \
   -device virtio-rng-pci,rng=viornd0 \
   -serial mon:stdio \
   -display none \
   -blockdev node-name=rom,driver=file,filename=/opt/homebrew/Cellar/qemu/9.0.2/share/qemu/edk2-aarch64-code.fd,read-only=true \
   -chardev socket,path=/tmp/qga_netbsd.sock,server=on,wait=off,id=qga0 \
   -device virtio-serial \
   -device virtconsole,chardev=qga0,name=org.qemu.guest_agent.0

This patch rectifies the operator precedence while assigning the NUL
terminator.

Fixes: c3f32c1

Signed-off-by: Sunil Nimmagadda <sunil@nimmagadda.net>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Link: https://lore.kernel.org/r/m15xppk9qg.fsf@nimmagadda.net
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

1 participant