public inbox for [email protected]
 help / color / mirror / Atom feed
From: Pavel Begunkov <[email protected]>
To: [email protected]
Cc: Jens Axboe <[email protected]>, [email protected]
Subject: [PATCH 2/3] io_uring: fix poll file assign deadlock
Date: Wed, 13 Apr 2022 16:10:34 +0100	[thread overview]
Message-ID: <2476d4ae46554324b599ee4055447b105f20a75a.1649862516.git.asml.silence@gmail.com> (raw)
In-Reply-To: <[email protected]>

We pass "unlocked" into io_assign_file() in io_poll_check_events(),
which can lead to double locking.

Fixes: 6bf9c47a3989 ("io_uring: defer file assignment")
Signed-off-by: Pavel Begunkov <[email protected]>
---
 fs/io_uring.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 3d6cbf77c89d..d06f1952fdfa 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5858,8 +5858,9 @@ static int io_poll_check_events(struct io_kiocb *req, bool locked)
 
 		if (!req->result) {
 			struct poll_table_struct pt = { ._key = req->apoll_events };
+			unsigned flags = locked ? 0 : IO_URING_F_UNLOCKED;
 
-			if (unlikely(!io_assign_file(req, IO_URING_F_UNLOCKED)))
+			if (unlikely(!io_assign_file(req, flags)))
 				req->result = -EBADF;
 			else
 				req->result = vfs_poll(req->file, &pt) & req->apoll_events;
-- 
2.35.1


  parent reply	other threads:[~2022-04-13 15:11 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-13 15:10 [PATCH 5.18 0/3] file assignment issues Pavel Begunkov
2022-04-13 15:10 ` [PATCH 1/3] io_uring: use right issue_flags for splice/tee Pavel Begunkov
2022-04-13 15:10 ` Pavel Begunkov [this message]
2022-04-13 15:10 ` [PATCH 3/3] io_uring: fix poll error reporting Pavel Begunkov
2022-04-13 16:26 ` [PATCH 5.18 0/3] file assignment issues Jens Axboe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=2476d4ae46554324b599ee4055447b105f20a75a.1649862516.git.asml.silence@gmail.com \
    [email protected] \
    [email protected] \
    [email protected] \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox