poll->canceled may be set from different contexts, even async, so
io_poll_rewait() should be prepared that it can change and not read it
twice.
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
---
fs/io_uring.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index de5822350345..376d9c875dc2 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4897,15 +4897,16 @@ static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
__acquires(&req->ctx->completion_lock)
{
struct io_ring_ctx *ctx = req->ctx;
+ bool canceled = READ_ONCE(poll->canceled);
- if (!req->result && !READ_ONCE(poll->canceled)) {
+ if (!req->result && !canceled) {
struct poll_table_struct pt = { ._key = poll->events };
req->result = vfs_poll(req->file, &pt) & poll->events;
}
spin_lock_irq(&ctx->completion_lock);
- if (!req->result && !READ_ONCE(poll->canceled)) {
+ if (!req->result && !canceled) {
add_wait_queue(poll->head, &poll->wait);
return true;
}
--
2.24.0
