From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:35824) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UNPKX-0005B1-HE for qemu-devel@nongnu.org; Wed, 03 Apr 2013 11:10:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UNPKT-0005RN-Gk for qemu-devel@nongnu.org; Wed, 03 Apr 2013 11:10:29 -0400 Received: from mail-ia0-x231.google.com ([2607:f8b0:4001:c02::231]:45069) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UNPKT-0005R3-D8 for qemu-devel@nongnu.org; Wed, 03 Apr 2013 11:10:25 -0400 Received: by mail-ia0-f177.google.com with SMTP id w33so1325852iag.8 for ; Wed, 03 Apr 2013 08:10:24 -0700 (PDT) Sender: fluxion Date: Wed, 3 Apr 2013 10:05:40 -0500 From: mdroth Message-ID: <20130403150540.GA26115@vm> References: <1364375446-24180-1-git-send-email-stefanha@redhat.com> <20130327091730.0c1bfe09@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130327091730.0c1bfe09@redhat.com> Subject: Re: [Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Luiz Capitulino Cc: Anthony Liguori , Juan Quintela , mprivozn@redhat.com, coreyb@linux.vnet.ibm.com, mjt@tls.msk.ru, david.pravec@nethost.cz, qemu-devel@nongnu.org, Stefan Hajnoczi On Wed, Mar 27, 2013 at 09:17:30AM -0400, Luiz Capitulino wrote: > On Wed, 27 Mar 2013 10:10:42 +0100 > Stefan Hajnoczi wrote: > > > There are several places where QEMU accidentally relies on the O_NONBLOCK state > > of passed file descriptors. Exposing O_NONBLOCK state makes it part of the QMP > > API whenever getfd or fdset_add_fd are used! > > > > Whether or not QEMU will use O_NONBLOCK is an implementation detail and should > > be hidden from QMP clients. > > > > This patch series addresses this in 3 steps: > > Nice series: > > Applied to the qmp branch, thanks. Hi Luiz, Eric/mjt have noted that this series fixes a number of issues in 1.4.0 and have requested it for 1.4.1 http://thread.gmane.org/gmane.comp.emulators.qemu/203851 The cut-off for 1.4.1 is Tuesday. Do you plan to send a pull for these soon? > > > > > 1. Fix callers of monitor_handle_fd_param(), monitor_fdset_get_fd(), and > > monitor_get_fd() that depend on O_NONBLOCK being set. Luckily there are > > only two instances and they are fixed in Patches 1 & 2. > > > > 2. Rename socket_set_nonblock() to qemu_set_nonblock() just like > > qemu_set_cloexec(). This makes code cleaner when working with arbitrary > > file descriptors that may not be sockets. See Patch 3. > > > > 3. Clear O_NONBLOCK when a chardev receives file descriptors. From now on QEMU > > can assume that passed file descriptors are in blocking mode. Simply use > > qemu_set_nonblock(fd) if you want to enable O_NONBLOCK. See Patch 4. > > > > This fixes live migration with recent libvirt. Libvirt checks if QEMU supports > > file descriptor passing and, if yes, hands QEMU a socket with O_NONBLOCK set. > > The migrate fd: code assumes the socket is in blocking mode. The result > > is a corrupted migration stream. For more info on this bug, see: > > > > https://bugzilla.redhat.com/show_bug.cgi?id=923124 > > > > Note that Michal Privoznik also sent a libvirt patch so > > that old QEMUs work with new libvirts: > > > > https://www.redhat.com/archives/libvir-list/2013-March/msg01486.html > > > > My patch series fixes the QMP API and allows old libvirts to work again with > > new QEMUs. > > > > v2: > > * Rename socket_set_nonblock() in Patch 1 to avoid code churn [eblake] > > * Avoid qemu_set_block(-1) calls that clobber errno [quintela] > > > > Stefan Hajnoczi (4): > > oslib-posix: rename socket_set_nonblock() to qemu_set_nonblock() > > net: ensure "socket" backend uses non-blocking fds > > qemu-socket: set passed fd non-blocking in socket_connect() > > chardev: clear O_NONBLOCK on SCM_RIGHTS file descriptors > > > > block/nbd.c | 2 +- > > block/sheepdog.c | 2 +- > > include/qemu/sockets.h | 4 ++-- > > migration.c | 2 +- > > nbd.c | 8 ++++---- > > net/socket.c | 13 +++++++++---- > > qemu-char.c | 11 +++++++---- > > savevm.c | 2 +- > > slirp/misc.c | 2 +- > > slirp/tcp_subr.c | 4 ++-- > > ui/vnc.c | 2 +- > > util/oslib-posix.c | 4 ++-- > > util/oslib-win32.c | 4 ++-- > > util/qemu-sockets.c | 5 +++-- > > 14 files changed, 37 insertions(+), 28 deletions(-) > > > >