6.6-stable review patch. If anyone has any objections, please let me know.
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From: Jens Axboe axboe@kernel.dk
Parts of commit b6f58a3f4aa8dba424356c7a69388a81f4459300 upstream.
Backport io_should_terminate_tw() helper to judge whether task_work should be run or terminated.
Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/io_uring.c | 3 +-- io_uring/io_uring.h | 13 +++++++++++++ io_uring/poll.c | 3 +-- io_uring/timeout.c | 2 +- 4 files changed, 16 insertions(+), 5 deletions(-)
--- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -1460,8 +1460,7 @@ static void io_req_task_cancel(struct io void io_req_task_submit(struct io_kiocb *req, struct io_tw_state *ts) { io_tw_lock(req->ctx, ts); - /* req->task == current here, checking PF_EXITING is safe */ - if (unlikely(req->task->flags & PF_EXITING)) + if (unlikely(io_should_terminate_tw())) io_req_defer_failed(req, -EFAULT); else if (req->flags & REQ_F_FORCE_ASYNC) io_queue_iowq(req); --- a/io_uring/io_uring.h +++ b/io_uring/io_uring.h @@ -394,6 +394,19 @@ static inline bool io_allowed_run_tw(str ctx->submitter_task == current); }
+/* + * Terminate the request if either of these conditions are true: + * + * 1) It's being executed by the original task, but that task is marked + * with PF_EXITING as it's exiting. + * 2) PF_KTHREAD is set, in which case the invoker of the task_work is + * our fallback task_work. + */ +static inline bool io_should_terminate_tw(void) +{ + return current->flags & (PF_KTHREAD | PF_EXITING); +} + static inline void io_req_queue_tw_complete(struct io_kiocb *req, s32 res) { io_req_set_res(req, res, 0); --- a/io_uring/poll.c +++ b/io_uring/poll.c @@ -258,8 +258,7 @@ static int io_poll_check_events(struct i { int v;
- /* req->task == current here, checking PF_EXITING is safe */ - if (unlikely(req->task->flags & PF_EXITING)) + if (unlikely(io_should_terminate_tw())) return -ECANCELED;
do { --- a/io_uring/timeout.c +++ b/io_uring/timeout.c @@ -307,7 +307,7 @@ static void io_req_task_link_timeout(str int ret = -ENOENT;
if (prev) { - if (!(req->task->flags & PF_EXITING)) { + if (!io_should_terminate_tw()) { struct io_cancel_data cd = { .ctx = req->ctx, .data = prev->cqe.user_data,