On Thu, Oct 26, 2017 at 13:09:25 +0100, Daniel Berrange wrote:
On Thu, Oct 26, 2017 at 03:04:08PM +0300, Nikolay Shirokovskiy
wrote:
> if image format probing is on and image format of iso file
> is not specified qemu fail to start a domain or change disk
> media giving errors like [1]. The problem is format is being
> detected as 'iso' and qemu expect format to be raw for iso
> images.
>
> It makes sense to me because iso refers to filesystem format
> in image not image format itself. Thus let's just convert
> iso to raw in case of qemu.
>
> There is a similar patch for storage pools - 0e5db762.
>
> [1] Unknown driver 'iso'
>
> ---
>
> ISO as image format was added right at the beginning by e266ded2f
> without any further comments. Maybe we just can drop ISO from image
> formats entirely as it is not image format or some hypervisors
> treat it in a special way?
Yeah, I'm inclined to say we can drop it. I don't recall either Xen or
QEMU caring about an 'iso' disk format
The hypervisors probably don't care about this but the storage driver
may care (At least for display purposes).
> src/qemu/qemu_domain.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
> index c7c9e94..3da9271 100644
> --- a/src/qemu/qemu_domain.c
> +++ b/src/qemu/qemu_domain.c
> @@ -6023,8 +6023,13 @@ qemuDomainDetermineDiskChain(virQEMUDriverPtr driver,
> if (virStorageFileGetMetadata(disk->src,
> uid, gid,
> cfg->allowDiskFormatProbing,
> - report_broken) < 0)
> + report_broken) < 0) {
> ret = -1;
> + goto cleanup;
> + }
> +
> + if (virDomainDiskGetFormat(disk) == VIR_STORAGE_FILE_ISO)
> + virDomainDiskSetFormat(disk, VIR_STORAGE_FILE_RAW);
This is not the right place and also not the correct way. We should
reject using ISO as a format if qemu will not support it as an invalid
configuration rather than silently turn it into raw.
The only acceptable place to turn ISO -> RAW is when it's comming from
the storage driver via <disk type=volume>