1. 26 Jan, 2021 2 commits
    • Pavel Begunkov's avatar
      io_uring: fix cancellation taking mutex while TASK_UNINTERRUPTIBLE · ca70f00b
      Pavel Begunkov authored
      do not call blocking ops when !TASK_RUNNING; state=2 set at
      	[<00000000ced9dbfc>] prepare_to_wait+0x1f4/0x3b0
      	kernel/sched/wait.c:262
      WARNING: CPU: 1 PID: 19888 at kernel/sched/core.c:7853
      	__might_sleep+0xed/0x100 kernel/sched/core.c:7848
      RIP: 0010:__might_sleep+0xed/0x100 kernel/sched/core.c:7848
      Call Trace:
       __mutex_lock_common+0xc4/0x2ef0 kernel/locking/mutex.c:935
       __mutex_lock kernel/locking/mutex.c:1103 [inline]
       mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1118
       io_wq_submit_work+0x39a/0x720 fs/io_uring.c:6411
       io_run_cancel fs/io-wq.c:856 [inline]
       io_wqe_cancel_pending_work fs/io-wq.c:990 [inline]
       io_wq_cancel_cb+0x614/0xcb0 fs/io-wq.c:1027
       io_uring_cancel_files fs/io_uring.c:8874 [inline]
       io_uring_cancel_task_requests fs/io_uring.c:8952 [inline]
       __io_uring_files_cancel+0x115d/0x19e0 fs/io_uring.c:9038
       io_uring_files_cancel include/linux/io_uring.h:51 [inline]
       do_exit+0x2e6/0x2490 kernel/exit.c:780
       do_group_exit+0x168/0x2d0 kernel/exit.c:922
       get_signal+0x16b5/0x2030 kernel/signal.c:2770
       arch_do_signal_or_restart+0x8e/0x6a0 arch/x86/kernel/signal.c:811
       handle_signal_work kernel/entry/common.c:147 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
       exit_to_user_mode_prepare+0xac/0x1e0 kernel/entry/common.c:201
       __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
       syscall_exit_to_user_mode+0x48/0x190 kernel/entry/common.c:302
       entry_SYSCALL_64_after_hwframe+0x44/0xa9
      
      Rewrite io_uring_cancel_files() to mimic __io_uring_task_cancel()'s
      counting scheme, so it does all the heavy work before setting
      TASK_UNINTERRUPTIBLE.
      
      Cc: stable@vger.kernel.org # 5.9+
      Reported-by: syzbot+f655445043a26a7cfab8@syzkaller.appspotmail.com
      Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
      [axboe: fix inverted task check]
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      ca70f00b
    • Pavel Begunkov's avatar
      io_uring: fix __io_uring_files_cancel() with TASK_UNINTERRUPTIBLE · a1bb3cd5
      Pavel Begunkov authored
      If the tctx inflight number haven't changed because of cancellation,
      __io_uring_task_cancel() will continue leaving the task in
      TASK_UNINTERRUPTIBLE state, that's not expected by
      __io_uring_files_cancel(). Ensure we always call finish_wait() before
      retrying.
      
      Cc: stable@vger.kernel.org # 5.9+
      Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
      Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      a1bb3cd5
  2. 25 Jan, 2021 3 commits
  3. 24 Jan, 2021 35 commits