bdrv_replace_child() calls bdrv_check_perm() with error_abort on
loosening permissions. However file-locking operations may fail even
in this case, for example on NFS. And this leads to Qemu crash.
Let's ignore such errors, as we do already on permission update commit
and abort.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
---
v2: - simplify expression [Eric]
- fix bug s/new_perm/new_shared
block/file-posix.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/block/file-posix.c b/block/file-posix.c
index db4cccbe51..736b4851e3 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -815,6 +815,20 @@ static int raw_handle_perm_lock(BlockDriverState *bs,
switch (op) {
case RAW_PL_PREPARE:
+ if ((s->perm | new_perm) == s->perm &&
+ (s->shared_perm & new_shared) == s->shared_perm)
+ {
+ /*
+ * We are going to unlock bytes, it should not fail. If fail,
+ * just report it and ignore, like we do for ABORT and COMMIT
+ * anyway.
+ */
+ ret = raw_check_lock_bytes(s->fd, new_perm, new_shared,
&local_err);
+ if (local_err) {
+ error_report_err(local_err);
+ }
+ return 0;
+ }
ret = raw_apply_lock_bytes(s, s->fd, s->perm | new_perm,
~s->shared_perm | ~new_shared,
false, errp);
--
2.18.0
