https://github.com/torvalds/linux
Revision a185f1db59f13de73aa470559030e90e50b34d93 authored by Pavel Begunkov on 23 March 2021, 10:52:38 UTC, committed by Jens Axboe on 24 March 2021, 12:55:11 UTC
WARNING: CPU: 1 PID: 27907 at fs/io_uring.c:7147 io_sq_thread_park+0xb5/0xd0 fs/io_uring.c:7147
CPU: 1 PID: 27907 Comm: iou-sqp-27905 Not tainted 5.12.0-rc4-syzkaller #0
RIP: 0010:io_sq_thread_park+0xb5/0xd0 fs/io_uring.c:7147
Call Trace:
io_ring_ctx_wait_and_kill+0x214/0x700 fs/io_uring.c:8619
io_uring_release+0x3e/0x50 fs/io_uring.c:8646
__fput+0x288/0x920 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:140
io_run_task_work fs/io_uring.c:2238 [inline]
io_run_task_work fs/io_uring.c:2228 [inline]
io_uring_try_cancel_requests+0x8ec/0xc60 fs/io_uring.c:8770
io_uring_cancel_sqpoll+0x1cf/0x290 fs/io_uring.c:8974
io_sqpoll_cancel_cb+0x87/0xb0 fs/io_uring.c:8907
io_run_task_work_head+0x58/0xb0 fs/io_uring.c:1961
io_sq_thread+0x3e2/0x18d0 fs/io_uring.c:6763
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
May happen that last ctx ref is killed in io_uring_cancel_sqpoll(), so
fput callback (i.e. io_uring_release()) is enqueued through task_work,
and run by same cancellation. As it's deeply nested we can't do parking
or taking sqd->lock there, because its state is unclear. So avoid
ctx ejection from sqd list from io_ring_ctx_wait_and_kill() and do it
in a clear context in io_ring_exit_work().
Fixes: f6d54255f423 ("io_uring: halt SQO submission on ctx exit")
Reported-by: syzbot+e3a3f84f5cecf61f0583@syzkaller.appspotmail.com
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e90df88b8ff2cabb14a7534601d35d62ab4cb8c7.1616496707.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 parent d81269f
Tip revision: a185f1db59f13de73aa470559030e90e50b34d93 authored by Pavel Begunkov on 23 March 2021, 10:52:38 UTC
io_uring: do ctx sqd ejection in a clear context
io_uring: do ctx sqd ejection in a clear context
Tip revision: a185f1d
| File | Mode | Size |
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | -rw-r--r-- | 16.4 KB |
| .cocciconfig | -rw-r--r-- | 59 bytes |
| .get_maintainer.ignore | -rw-r--r-- | 71 bytes |
| .gitattributes | -rw-r--r-- | 62 bytes |
| .gitignore | -rw-r--r-- | 1.9 KB |
| .mailmap | -rw-r--r-- | 18.5 KB |
| COPYING | -rw-r--r-- | 496 bytes |
| CREDITS | -rw-r--r-- | 98.3 KB |
| Kbuild | -rw-r--r-- | 1.3 KB |
| Kconfig | -rw-r--r-- | 555 bytes |
| MAINTAINERS | -rw-r--r-- | 577.0 KB |
| Makefile | -rw-r--r-- | 64.6 KB |
| README | -rw-r--r-- | 727 bytes |
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