[v4,0/2] vpc: Read images exported from Azure correctly

Message

Vitaly Kuznetsov Dec. 12, 2024, 1:45 p.m. UTC

Changes since v3:
- Split the change into two patches [Philippe Mathieu-Daude].

It was found that 'qemu-nbd' is not able to work with some disk images
exported from Azure as it uses a currently unknown 'wa\0\0' 'creator app'
signature. QEMU currently supports two methods for determining the image
size: CHS and 'current_size' and the list of known 'creator app's is used
to decide between the two. Invert the logic in QEMU and make 'current_size'
the default as it seems that VPC and old QEMU are the only two legacy apps
where preferring CHS makes sense.

Vitaly Kuznetsov (2):
  vpc: Split off vpc_ignore_current_size() helper
  vpc: Read images exported from Azure correctly

 block/vpc.c | 65 ++++++++++++++++++++++++++++-------------------------
 1 file changed, 35 insertions(+), 30 deletions(-)

Comments

Vitaly Kuznetsov Jan. 8, 2025, 4:03 p.m. UTC | #1

Vitaly Kuznetsov <[e-mail]> writes:

> Changes since v3:
> - Split the change into two patches [Philippe Mathieu-Daude].
>
> It was found that 'qemu-nbd' is not able to work with some disk images
> exported from Azure as it uses a currently unknown 'wa\0\0' 'creator app'
> signature. QEMU currently supports two methods for determining the image
> size: CHS and 'current_size' and the list of known 'creator app's is used
> to decide between the two. Invert the logic in QEMU and make 'current_size'
> the default as it seems that VPC and old QEMU are the only two legacy apps
> where preferring CHS makes sense.
>
> Vitaly Kuznetsov (2):
>   vpc: Split off vpc_ignore_current_size() helper
>   vpc: Read images exported from Azure correctly

Ping?

Kevin Wolf Jan. 16, 2025, 2:03 p.m. UTC | #2

Am 12.12.2024 um 14:45 hat Vitaly Kuznetsov geschrieben:
> Changes since v3:
> - Split the change into two patches [Philippe Mathieu-Daude].
> 
> It was found that 'qemu-nbd' is not able to work with some disk images
> exported from Azure as it uses a currently unknown 'wa\0\0' 'creator app'
> signature. QEMU currently supports two methods for determining the image
> size: CHS and 'current_size' and the list of known 'creator app's is used
> to decide between the two. Invert the logic in QEMU and make 'current_size'
> the default as it seems that VPC and old QEMU are the only two legacy apps
> where preferring CHS makes sense.
> 
> Vitaly Kuznetsov (2):
>   vpc: Split off vpc_ignore_current_size() helper
>   vpc: Read images exported from Azure correctly

Thanks, applied to the block branch.

Kevin