Re: [Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors
On Wed, Mar 27, 2013 at 09:17:30AM -0400, Luiz Capitulino wrote: On Wed, 27 Mar 2013 10:10:42 +0100 Stefan Hajnoczi stefa...@redhat.com 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:foo 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 mpriv...@redhat.com 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(-)
Re: [Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors
On Wed, 3 Apr 2013 11:24:38 -0400 Luiz Capitulino lcapitul...@redhat.com wrote: On Wed, 3 Apr 2013 10:05:40 -0500 mdroth mdr...@linux.vnet.ibm.com wrote: On Wed, Mar 27, 2013 at 09:17:30AM -0400, Luiz Capitulino wrote: On Wed, 27 Mar 2013 10:10:42 +0100 Stefan Hajnoczi stefa...@redhat.com 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? Sure, I can do that. And thanks to remind me. Actually, I can't cherry-pick it cleanly. Stefan, would you mind to backport this series to v1.4.1 yourself?
Re: [Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors
On Wed, 3 Apr 2013 10:05:40 -0500 mdroth mdr...@linux.vnet.ibm.com wrote: On Wed, Mar 27, 2013 at 09:17:30AM -0400, Luiz Capitulino wrote: On Wed, 27 Mar 2013 10:10:42 +0100 Stefan Hajnoczi stefa...@redhat.com 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? Sure, I can do that. And thanks to remind me.
[Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors
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: 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:foo 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 mpriv...@redhat.com 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(-) -- 1.8.1.4
Re: [Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors
On 03/27/2013 03:10 AM, 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: 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. Description is now off after rebase, but the cover letter isn't committed, so no big deal. 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. Series: Reviewed-by: Eric Blake ebl...@redhat.com 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 -- Eric Blake eblake redhat com+1-919-301-3266 Libvirt virtualization library http://libvirt.org signature.asc Description: OpenPGP digital signature
Re: [Qemu-devel] [PATCH v2 0/4] monitor: do not rely on O_NONBLOCK for passed file descriptors
On Wed, 27 Mar 2013 10:10:42 +0100 Stefan Hajnoczi stefa...@redhat.com 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. 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:foo 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 mpriv...@redhat.com 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(-)
