While a zero allocation in safezero should be fine it isn't when we use posix_fallocate which returns EINVAL on a zero allocation. While we could skip the zero allocation in safezero_posix_fallocate it's an optimization to do it for all allocations. This fixes vm installation via virtinst for me which otherwise aborts like: Starting install... Retrieving file linux... | 5.9 MB 00:01 ... Retrieving file initrd.gz... | 29 MB 00:07 ... ERROR Couldn't create storage volume 'virtinst-linux.sBgds4': 'cannot fill file '/var/lib/libvirt/boot/virtinst-linux.sBgds4': Invalid argument' --- No idea while this didn't show up earlier though. src/storage/storage_backend.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c index db49739..0418473 100644 --- a/src/storage/storage_backend.c +++ b/src/storage/storage_backend.c @@ -455,7 +455,7 @@ createRawFile(int fd, virStorageVolDefPtr vol, pos = inputvol->target.capacity - remain; } - if (need_alloc) { + if (need_alloc && (vol->target.allocation - pos > 0)) { if (safezero(fd, pos, vol->target.allocation - pos) < 0) { ret = -errno; virReportSystemError(errno, _("cannot fill file '%s'"), -- 2.1.4