diff options
author | Tomoki Sekiyama <tomoki.sekiyama@hds.com> | 2013-10-01 17:09:53 -0400 |
---|---|---|
committer | Michael Roth <mdroth@linux.vnet.ibm.com> | 2013-12-09 14:45:41 -0600 |
commit | 9388fdb603e69d1c251f9bdfaac575ad3258583a (patch) | |
tree | 61feb46c31d6aad44f05528f17c84fafa5e8621c | |
parent | 68a1ac19a1a24bc47c8c6db1bca7026e2199cc32 (diff) |
qemu-ga: execute fsfreeze-freeze in reverse order of mounts
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 freezes filesystems in reverse order of mounts.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
*fix up commit msg
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
(cherry picked from commit e5d9adbdab972a2172815c1174aed3fabcc448f1)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
-rw-r--r-- | qga/commands-posix.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/qga/commands-posix.c b/qga/commands-posix.c index e199738c71..f453132b92 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); |