summaryrefslogtreecommitdiff
path: root/io_uring
diff options
context:
space:
mode:
authorJens Axboe <axboe@kernel.dk>2023-06-17 19:50:24 -0600
committerJens Axboe <axboe@kernel.dk>2023-06-17 20:21:52 -0600
commitef7dfac51d8ed961b742218f526bd589f3900a59 (patch)
tree4c7daa6f4d2b65aef33d3e115bf8775aa4163fde /io_uring
parentadeaa3f290ecf7f6a6a5c53219a4686cbdff5fbd (diff)
downloadlwn-ef7dfac51d8ed961b742218f526bd589f3900a59.tar.gz
lwn-ef7dfac51d8ed961b742218f526bd589f3900a59.zip
io_uring/poll: serialize poll linked timer start with poll removal
We selectively grab the ctx->uring_lock for poll update/removal, but we really should grab it from the start to fully synchronize with linked timeouts. Normally this is indeed the case, but if requests are forced async by the application, we don't fully cover removal and timer disarm within the uring_lock. Make this simpler by having consistent locking state for poll removal. Cc: stable@vger.kernel.org # 6.1+ Reported-by: Querijn Voet <querijnqyn@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
-rw-r--r--io_uring/poll.c9
1 files changed, 4 insertions, 5 deletions
diff --git a/io_uring/poll.c b/io_uring/poll.c
index c90e47dc1e29..a78b8af7d9ab 100644
--- a/io_uring/poll.c
+++ b/io_uring/poll.c
@@ -977,8 +977,9 @@ int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
struct io_hash_bucket *bucket;
struct io_kiocb *preq;
int ret2, ret = 0;
- struct io_tw_state ts = {};
+ struct io_tw_state ts = { .locked = true };
+ io_ring_submit_lock(ctx, issue_flags);
preq = io_poll_find(ctx, true, &cd, &ctx->cancel_table, &bucket);
ret2 = io_poll_disarm(preq);
if (bucket)
@@ -990,12 +991,10 @@ int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
goto out;
}
- io_ring_submit_lock(ctx, issue_flags);
preq = io_poll_find(ctx, true, &cd, &ctx->cancel_table_locked, &bucket);
ret2 = io_poll_disarm(preq);
if (bucket)
spin_unlock(&bucket->lock);
- io_ring_submit_unlock(ctx, issue_flags);
if (ret2) {
ret = ret2;
goto out;
@@ -1019,7 +1018,7 @@ found:
if (poll_update->update_user_data)
preq->cqe.user_data = poll_update->new_user_data;
- ret2 = io_poll_add(preq, issue_flags);
+ ret2 = io_poll_add(preq, issue_flags & ~IO_URING_F_UNLOCKED);
/* successfully updated, don't complete poll request */
if (!ret2 || ret2 == -EIOCBQUEUED)
goto out;
@@ -1027,9 +1026,9 @@ found:
req_set_fail(preq);
io_req_set_res(preq, -ECANCELED, 0);
- ts.locked = !(issue_flags & IO_URING_F_UNLOCKED);
io_req_task_complete(preq, &ts);
out:
+ io_ring_submit_unlock(ctx, issue_flags);
if (ret < 0) {
req_set_fail(req);
return ret;