Hello Jens Axboe,
Commit 313314db5bcb ("io_uring/poll: get rid of unlocked cancel
hash") from Sep 30, 2024 (linux-next), leads to the following Smatch
static checker warning:
io_uring/poll.c:932 io_poll_remove()
warn: duplicate check 'ret2' (previous on line 930)
io_uring/poll.c
919 int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
920 {
921 struct io_poll_update *poll_update = io_kiocb_to_cmd(req, struct io_poll_update);
922 struct io_ring_ctx *ctx = req->ctx;
923 struct io_cancel_data cd = { .ctx = ctx, .data = poll_update->old_user_data, };
924 struct io_kiocb *preq;
925 int ret2, ret = 0;
926
927 io_ring_submit_lock(ctx, issue_flags);
928 preq = io_poll_find(ctx, true, &cd);
929 ret2 = io_poll_disarm(preq);
930 if (!ret2)
931 goto found;
--> 932 if (ret2) {
933 ret = ret2;
934 goto out;
935 }
A lot of the function is dead code now. ;)
936 found:
937 if (WARN_ON_ONCE(preq->opcode != IORING_OP_POLL_ADD)) {
938 ret = -EFAULT;
939 goto out;
940 }
941
942 if (poll_update->update_events || poll_update->update_user_data) {
943 /* only mask one event flags, keep behavior flags */
944 if (poll_update->update_events) {
945 struct io_poll *poll = io_kiocb_to_cmd(preq, struct io_poll);
946
947 poll->events &= ~0xffff;
948 poll->events |= poll_update->events & 0xffff;
949 poll->events |= IO_POLL_UNMASK;
950 }
951 if (poll_update->update_user_data)
952 preq->cqe.user_data = poll_update->new_user_data;
953
954 ret2 = io_poll_add(preq, issue_flags & ~IO_URING_F_UNLOCKED);
955 /* successfully updated, don't complete poll request */
956 if (!ret2 || ret2 == -EIOCBQUEUED)
957 goto out;
958 }
959
960 req_set_fail(preq);
961 io_req_set_res(preq, -ECANCELED, 0);
962 preq->io_task_work.func = io_req_task_complete;
963 io_req_task_work_add(preq);
964 out:
965 io_ring_submit_unlock(ctx, issue_flags);
966 if (ret < 0) {
967 req_set_fail(req);
968 return ret;
969 }
970 /* complete update request, we're done with it */
971 io_req_set_res(req, ret, 0);
972 return IOU_OK;
973 }
regards,
dan carpenter
