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From: Scott Tsai <scottt.tw@gmail.com>
To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] Don't leak file descriptors
Date: Fri, 13 Nov 2009 23:36:05 +0800	[thread overview]
Message-ID: <ef2f888d0911130736u18686ae3u631f9e97d1592357@mail.gmail.com> (raw)
In-Reply-To: <1258125436-23759-1-git-send-email-kwolf@redhat.com>

On Fri, Nov 13, 2009 at 11:17 PM, Kevin Wolf <kwolf@redhat.com> wrote:
> We're leaking file descriptors to child processes. Set FD_CLOEXEC on file
> descriptors that don't need to be passed to children to stop this misbehaviour.

Since qemu is a multi threaded program, how about opening those file
descriptors with the equivalent of O_CLOEXEC set to avoid the race
condition when a fork comes between the 'open/socket/accept' operation
and the 'fcntl'?

We could create helper functions like 'qemu_socket_cloexec'.
The implementation of qemu_socket_cloexec would use the new system
calls and flags listed in:
http://udrepper.livejournal.com/20407.html
if available and fall back to separate 'open' and 'fcnt' operations
when not building with a new enough glibc.

  reply	other threads:[~2009-11-13 15:36 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-11-13 15:17 [Qemu-devel] [PATCH] Don't leak file descriptors Kevin Wolf
2009-11-13 15:36 ` Scott Tsai [this message]
2009-11-16  2:15   ` Jamie Lokier
2009-11-13 15:41 ` Nathan Froyd
2009-11-13 15:44   ` Kevin Wolf
2009-11-13 21:05 ` Blue Swirl
2009-11-16 12:47   ` Kevin Wolf
2009-11-16 16:21     ` Blue Swirl
2009-11-16 16:46       ` Avi Kivity
2009-11-16 23:05       ` Jamie Lokier
2009-11-16 23:10         ` Jamie Lokier
2009-11-17  9:12         ` Kevin Wolf
2009-11-17 20:28           ` Blue Swirl
2009-11-16 23:26 ` Anthony Liguori
2009-11-16 23:44   ` Jamie Lokier
2009-11-17  9:00   ` Kevin Wolf

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