diff options
Diffstat (limited to 'block/io.c')
| -rw-r--r-- | block/io.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/block/io.c b/block/io.c index bb0a254def..4e4cb556c5 100644 --- a/block/io.c +++ b/block/io.c @@ -2497,8 +2497,12 @@ static int coroutine_fn bdrv_co_block_status(BlockDriverState *bs, * non-protocol nodes, and then it is never used. However, filling * the cache requires an RCU update, so double check here to avoid * such an update if possible. + * + * Check want_zero, because we only want to update the cache when we + * have accurate information about what is zero and what is data. */ - if (ret == (BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID) && + if (want_zero && + ret == (BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID) && QLIST_EMPTY(&bs->children)) { /* |