[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 4/4] chardev: clear O_NONBLOCK on SCM_RIGHTS fil
|
From: |
Juan Quintela |
|
Subject: |
Re: [Qemu-devel] [PATCH 4/4] chardev: clear O_NONBLOCK on SCM_RIGHTS file descriptors |
|
Date: |
Tue, 26 Mar 2013 17:38:55 +0100 |
|
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/24.2 (gnu/linux) |
Stefan Hajnoczi <address@hidden> wrote:
> When we receive a file descriptor over a UNIX domain socket the
> O_NONBLOCK flag is preserved. Clear the O_NONBLOCK flag and rely on
> QEMU file descriptor users like migration, SPICE, VNC, block layer, and
> others to set non-blocking only when necessary.
>
> This change ensures we don't accidentally expose O_NONBLOCK in the QMP
> API. QMP clients should not need to get the non-blocking state
> "correct".
>
> A recent real-world example was when libvirt passed a non-blocking TCP
> socket for migration where we expected a blocking socket. The source
> QEMU produced a corrupted migration stream since its code did not cope
> with non-blocking sockets.
>
> Signed-off-by: Stefan Hajnoczi <address@hidden>
Acked-by: Juan Quintela <address@hidden>
- [Qemu-devel] [PATCH 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors, Stefan Hajnoczi, 2013/03/26
- [Qemu-devel] [PATCH 2/4] qemu-socket: set passed fd non-blocking in socket_connect(), Stefan Hajnoczi, 2013/03/26
- [Qemu-devel] [PATCH 4/4] chardev: clear O_NONBLOCK on SCM_RIGHTS file descriptors, Stefan Hajnoczi, 2013/03/26
- [Qemu-devel] [PATCH 1/4] net: ensure "socket" backend uses non-blocking fds, Stefan Hajnoczi, 2013/03/26
- [Qemu-devel] [PATCH 3/4] oslib-posix: rename socket_set_nonblock() to qemu_set_nonblock(), Stefan Hajnoczi, 2013/03/26
- Re: [Qemu-devel] [PATCH 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors, liu ping fan, 2013/03/27