Quoting Tomoki Sekiyama (2013-10-01 16:09:53) > Currently, fsfreeze-freeze may cause deadlock if a guest has loopback mounts > of image files in its disk; e.g.: > > # mount | grep ^/ > /dev/vda1 / type ext4 (rw,noatime,seclabel,data=ordered) > /tmp/disk.img on /mnt type ext4 (rw,relatime,seclabel) > > To avoid the deadlock, this freeze filesystems in reverse order of mounts. > > Signed-off-by: Tomoki Sekiyama <tomoki.sekiy...@hds.com>
Thanks, applied to qga tree: https://github.com/mdroth/qemu/commits/qga > --- > qga/commands-posix.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/qga/commands-posix.c b/qga/commands-posix.c > index e199738..f453132 100644 > --- a/qga/commands-posix.c > +++ b/qga/commands-posix.c > @@ -566,7 +566,7 @@ typedef struct FsMount { > QTAILQ_ENTRY(FsMount) next; > } FsMount; > > -typedef QTAILQ_HEAD(, FsMount) FsMountList; > +typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList; > > static void free_fs_mount_list(FsMountList *mounts) > { > @@ -728,7 +728,7 @@ int64_t qmp_guest_fsfreeze_freeze(Error **err) > /* cannot risk guest agent blocking itself on a write in this state */ > ga_set_frozen(ga_state); > > - QTAILQ_FOREACH(mount, &mounts, next) { > + QTAILQ_FOREACH_REVERSE(mount, &mounts, FsMountList, next) { > fd = qemu_open(mount->dirname, O_RDONLY); > if (fd == -1) { > error_setg_errno(err, errno, "failed to open %s", > mount->dirname);
