Re: [PATCH v2] block/vhdx: Support vhdx image only with 512 bytes logical sector size

[Max Reitz]

On 07.08.20 12:03, Swapnil Ingle wrote:
> block/vhdx uses qemu block layer where sector size is always 512 bytes.
> This may have issues  with 4K logical sector sized vhdx image.
> 
> For e.g qemu-img convert on such images fails with following assert:
> 
> $qemu-img convert -f vhdx -O raw 4KTest1.vhdx test.raw
> qemu-img: util/iov.c:388: qiov_slice: Assertion `offset + len <=
> qiov->size' failed.
> Aborted
> 
> This patch adds an check to return ENOTSUP for vhdx images which
> have logical sector size other than 512 bytes.
> 
> Signed-off-by: Swapnil Ingle <swapnil.ingle@nutanix.com>
> ---
> v2: Fixed commit message, suggested by Philippe Mathieu-Daude
> ---
>  block/vhdx.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

Oh, sorry, yes.  Thanks!

Applied to my block branch:

https://git.xanclic.moe/XanClic/qemu/commits/branch/block

Max


(Further information for others: The vhdx code assumes all over the
place that the vhdx sectors have the same size as “block layer sectors”.
 Fixing this seems by no means trivial.  I assume images with 4k sectors
have never worked, so this commit doesn’t remove support, it just makes
the vhdx driver safely exit before it can do something wrong.)