From: David Howells <dhowells@redhat.com>
To: Jann Horn <jannh@google.com>
Cc: dhowells@redhat.com, Alexander Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com
Subject: Re: [PATCH] fs/pipe: Fix lockdep false-positive in watchqueue pipe_write()
Date: Fri, 24 Nov 2023 15:53:47 +0000 [thread overview]
Message-ID: <1210483.1700841227@warthog.procyon.org.uk> (raw)
In-Reply-To: <20231124150822.2121798-1-jannh@google.com>
Jann Horn <jannh@google.com> wrote:
> + /*
> + * Reject writing to watch queue pipes before the point where we lock
> + * the pipe.
> + * Otherwise, lockdep would be unhappy if the caller already has another
> + * pipe locked.
> + * If we had to support locking a normal pipe and a notification pipe at
> + * the same time, we could set up lockdep annotations for that, but
> + * since we don't actually need that, it's simpler to just bail here.
> + */
> + if (pipe_has_watch_queue(pipe))
> + return -EXDEV;
> +
Linus wanted it to be possible for the user to write to a notificaiton pipe.
David
next prev parent reply other threads:[~2023-11-24 15:53 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-24 15:08 [PATCH] fs/pipe: Fix lockdep false-positive in watchqueue pipe_write() Jann Horn
2023-11-24 15:19 ` Christian Brauner
2023-11-24 15:53 ` David Howells [this message]
2023-11-24 16:02 ` Christian Brauner
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=1210483.1700841227@warthog.procyon.org.uk \
--to=dhowells@redhat.com \
--cc=brauner@kernel.org \
--cc=jannh@google.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
--cc=viro@zeniv.linux.org.uk \
/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