On 06/24/2015 01:05 AM, Jindřich Makovička wrote: > Fixes a crash during image compression > > Signed-off-by: Jindřich Makovička <makov...@gmail.com> > --- > block/qcow2-refcount.c | 22 ++++++++++++---------- > 1 file changed, 12 insertions(+), 10 deletions(-) >
Rich Jones already confirmed that this patch fixes a bug he can reliably reproduce: https://bugzilla.redhat.com/show_bug.cgi?id=1214855 - Cole > diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c > index 0632fc3..b0ee42d 100644 > --- a/block/qcow2-refcount.c > +++ b/block/qcow2-refcount.c > @@ -940,19 +940,21 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int > size) > } > > free_in_cluster = s->cluster_size - offset_into_cluster(s, offset); > - if (!offset || free_in_cluster < size) { > - int64_t new_cluster = alloc_clusters_noref(bs, s->cluster_size); > - if (new_cluster < 0) { > - return new_cluster; > - } > + do { > + if (!offset || free_in_cluster < size) { > + int64_t new_cluster = alloc_clusters_noref(bs, s->cluster_size); > + if (new_cluster < 0) { > + return new_cluster; > + } > > - if (!offset || ROUND_UP(offset, s->cluster_size) != new_cluster) { > - offset = new_cluster; > + if (!offset || ROUND_UP(offset, s->cluster_size) != new_cluster) > { > + offset = new_cluster; > + } > } > - } > > - assert(offset); > - ret = update_refcount(bs, offset, size, 1, false, QCOW2_DISCARD_NEVER); > + assert(offset); > + ret = update_refcount(bs, offset, size, 1, false, > QCOW2_DISCARD_NEVER); > + } while (ret == -EAGAIN); > if (ret < 0) { > return ret; > } >
