When creating a logical volume with virStorageVolCreateXMLFrom, "qemu-img convert" is called internally if clonevol is a file volume. Then, vol->target.format is used as output_fmt parameter but the target.format of logical volumes is always 0 because logical volumes haven't the volume format type element. Fortunately, 0 was treated as RAW file format before commit f772b3d9, so there was no problem. But now, 0 is treated as the type of none, qemu-img fails with "Unknown file format 'none'". This patch fixes this issue by treating output block devices as RAW file format like for input block devices. Signed-off-by: Atsushi Kumagai <kumagai-atsushi(a)mxc.nes.nec.co.jp&gt; diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c index bb58d4a..2551f1f 100644 --- a/src/storage/storage_backend.c +++ b/src/storage/storage_backend.c @@ -652,7 +652,12 @@ virStorageBackendCreateQemuImgCmd(virConnectPtr conn, unsigned long long int size_arg; bool preallocate = false; - const char *type = virStorageFileFormatTypeToString(vol->target.format); + /* Treat output block devices as 'raw' format */ + const char *type = + virStorageFileFormatTypeToString(vol->type == VIR_STORAGE_VOL_BLOCK ? + VIR_STORAGE_FILE_RAW : + vol->target.format); + const char *backingType = vol->backingStore.path ? virStorageFileFormatTypeToString(vol->backingStore.format) : NULL; -- 1.7.1