| Message ID | 1460040754-108375-1-git-send-email-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
Am 07.04.2016 um 16:52 hat Paolo Bonzini geschrieben: > bdrv_pwrite_sync used to return zero or negative error, while blk_pwrite returns > the number of written bytes when successful. This caused VPC image creation > to fail spectacularly: it wrote the first 512 bytes, and then exited immediately > because of the non-zero answer from blk_pwrite. But the truly spectacular part > is that it returns a positive value (the 512 that blk_pwrite returned) causing > everyone to believe that it succeeded. > > This fixes qemu-iotests with vpc format. > > Fixes: b8f45cdf7827e39f9a1e6cc446f5972cc6144237 > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Thanks, applied to the block branch. Kevin
diff --git a/block/vpc.c b/block/vpc.c index 8830b5b..3713ec3 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -775,7 +775,7 @@ static int create_dynamic_disk(BlockBackend *blk, uint8_t *buf, num_bat_entries = (total_sectors + block_size / 512) / (block_size / 512); ret = blk_pwrite(blk, offset, buf, HEADER_SIZE); - if (ret) { + if (ret < 0) { goto fail; }
bdrv_pwrite_sync used to return zero or negative error, while blk_pwrite returns the number of written bytes when successful. This caused VPC image creation to fail spectacularly: it wrote the first 512 bytes, and then exited immediately because of the non-zero answer from blk_pwrite. But the truly spectacular part is that it returns a positive value (the 512 that blk_pwrite returned) causing everyone to believe that it succeeded. This fixes qemu-iotests with vpc format. Fixes: b8f45cdf7827e39f9a1e6cc446f5972cc6144237 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- block/vpc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)