Re: [PATCH 0/2] block-backend: Retain permissions after migration

[Peng Liang]

On 11/25/2021 9:53 PM, Hanna Reitz wrote:
> Hi,
> 
> Peng Liang has reported an issue regarding migration of raw images here:
> https://lists.nongnu.org/archive/html/qemu-block/2021-11/msg00673.html
> 
> It turns out that after migrating, all permissions are shared when they
> weren’t before.  The cause of the problem is that we deliberately delay
> restricting the shared permissions until migration is really done (until
> the runstate is no longer INMIGRATE) and first share all permissions;
> but this causes us to lose the original shared permission mask and
> overwrites it with BLK_PERM_ALL, so once we do try to restrict the
> shared permissions, we only again share them all.
> 
> Fix this by saving the set of shared permissions through the first
> blk_perm_set() call that shares all; and add a regression test.
> 
> 
> I don’t believe we have to fix this in 6.2, because I think this bug has
> existed for four years now.  (I.e. it isn’t critical, and it’s no
> regression.)
> 
> 
> Hanna Reitz (2):
>   block-backend: Retain permissions after migration
>   iotests/migration-permissions: New test
> 
>  block/block-backend.c                         |  11 ++
>  .../qemu-iotests/tests/migration-permissions  | 101 ++++++++++++++++++
>  .../tests/migration-permissions.out           |   5 +
>  3 files changed, 117 insertions(+)
>  create mode 100755 tests/qemu-iotests/tests/migration-permissions
>  create mode 100644 tests/qemu-iotests/tests/migration-permissions.out
> 

Hi Hanna,
QEMU 6.3 development tree has been opened.  Will this fix be merged in 6.3?

Thanks,
Peng