| Message ID | 1275069692-5756-7-git-send-email-kwolf@redhat.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index fa78e46..465d5d3 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -402,6 +402,10 @@ static int write_refcount_block_entries(BDRVQcowState *s, return 0; } + if (first_index < 0) { + return 0; + } + first_index &= ~(REFCOUNTS_PER_SECTOR - 1); last_index = (last_index + REFCOUNTS_PER_SECTOR) & ~(REFCOUNTS_PER_SECTOR - 1);
After it is done with updating refcounts in the cache, update_refcount writes all changed entries to disk. If a refcount block allocation fails, however, there was no change yet and therefore first_index = last_index = -1. Don't treat -1 as a normal sector index (resulting in a 512 byte write!) but return without updating anything in this case. Signed-off-by: Kevin Wolf <kwolf@redhat.com> (cherry picked from commit 86fa8da83771238de55dc44819a1a27bafef5353) --- block/qcow2-refcount.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)