================================================================== BUG: KCSAN: data-race in exit_signals / kthread_unpark write to 0xffff888047f7c02c of 4 bytes by task 17307 on cpu 0: exit_signals+0x118/0x550 kernel/signal.c:2869 do_exit+0x197/0x15e0 kernel/exit.c:781 kthread+0x213/0x230 kernel/kthread.c:294 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 read to 0xffff888047f7c02c of 4 bytes by task 17300 on cpu 1: to_kthread kernel/kthread.c:83 [inline] kthread_unpark+0x1f/0x150 kernel/kthread.c:536 kthread_stop+0xa6/0x2c0 kernel/kthread.c:619 sdr_cap_stop_streaming+0x16e/0x190 drivers/media/test-drivers/vivid/vivid-sdr-cap.c:312 __vb2_queue_cancel+0x72/0x6f0 drivers/media/common/videobuf2/videobuf2-core.c:1937 vb2_core_streamoff drivers/media/common/videobuf2/videobuf2-core.c:2094 [inline] __vb2_cleanup_fileio drivers/media/common/videobuf2/videobuf2-core.c:2642 [inline] vb2_core_queue_release+0x37/0x1a0 drivers/media/common/videobuf2/videobuf2-core.c:2362 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:938 [inline] _vb2_fop_release drivers/media/common/videobuf2/videobuf2-v4l2.c:1111 [inline] vb2_fop_release+0xee/0x150 drivers/media/common/videobuf2/videobuf2-v4l2.c:1125 vivid_fop_release+0x292/0x790 drivers/media/test-drivers/vivid/vivid-core.c:634 v4l2_release+0xfa/0x1f0 drivers/media/v4l2-core/v4l2-dev.c:457 __fput+0x263/0x4f0 fs/file_table.c:280 ____fput+0x11/0x20 fs/file_table.c:313 task_work_run+0x8e/0x110 kernel/task_work.c:140 get_signal+0x149f/0x14e0 kernel/signal.c:2558 arch_do_signal_or_restart+0x2a/0x270 arch/x86/kernel/signal.c:789 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+0x11a/0x1b0 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 17300 Comm: syz-executor.1 Tainted: G W 5.12.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================