On 1/13/25 16:03, Bui Quang Minh wrote:
In io_uring_try_cancel_requests, we check whether sq_data->thread == current to determine if the function is called by the SQPOLL thread to do iopoll when IORING_SETUP_SQPOLL is set. This check can race with the SQPOLL thread termination. io_uring_cancel_generic is used in 2 places: io_uring_cancel_generic and io_ring_exit_work. In io_uring_cancel_generic, we have the information whether the current is SQPOLL thread already. And the SQPOLL thread never reaches io_ring_exit_work. So to avoid the racy check, this commit adds a boolean flag to io_uring_try_cancel_requests to determine if the caller is SQPOLL thread.
I think the comment is excessive, but let's leave it at that if you don't want to respin it. Reviewed-by: Pavel Begunkov <asml.silence@xxxxxxxxx> -- Pavel Begunkov