Re: [PATCH v3 0/2] Fix persistent grants negotiation with a behavior change

[SeongJae Park]

Hi all,

On Fri, 15 Jul 2022 17:55:19 +0000 SeongJae Park <sj@xxxxxxxxxx> wrote:

> The first patch of this patchset fixes 'feature_persistent' parameter
> handling in 'blkback' to respect the frontend's persistent grants
> support always.  The fix makes a behavioral change, so the second patch
> makes the counterpart of 'blkfront' to consistently follow the behavior
> change.

I made the behavior change as requested by Andrii[1].  I therefore made similar
behavior change to blkfront and Cc-ed stable for the second change, too.

To make the change history clear and reduce the stable side overhead, however,
it might be better to apply the v2, which don't make behavior change but only
fix the issue, Cc stable@ for it, make the behavior change commits for both
blkback and blkfront, update the documents, and don't Cc stable@ for the
behavior change and documents update commits.

One downside of that would be that it will make a behavioral difference in
pre-5.19.x and post-5.19.x.

I think both downsides are not critical, so posted this patchset in this shape.
If anyone prefer some changes, please let me know, though.

[1] https://lore.kernel.org/xen-devel/CAJwUmVB6H3iTs-C+U=v-pwJB7-_ZRHPxHzKRJZ22xEPW7z8a=g@xxxxxxxxxxxxxx/


Thanks,
SJ

> 
> Changes from v2
> (https://lore.kernel.org/xen-devel/20220714224410.51147-1-sj@xxxxxxxxxx/)
> - Keep the behavioral change of v1
> - Update blkfront's counterpart to follow the changed behavior
> - Update documents for the changed behavior
> 
> Changes from v1
> (https://lore.kernel.org/xen-devel/20220106091013.126076-1-mheyne@xxxxxxxxx/)
> - Avoid the behavioral change
>   (https://lore.kernel.org/xen-devel/20220121102309.27802-1-sj@xxxxxxxxxx/)
> - Rebase on latest xen/tip/linux-next
> - Re-work by SeongJae Park <sj@xxxxxxxxxx>
> - Cc stable@
> 
> 
> 
> Maximilian Heyne (1):
>   xen, blkback: fix persistent grants negotiation
> 
> SeongJae Park (1):
>   xen-blkfront: Apply 'feature_persistent' parameter when connect
> 
>  Documentation/ABI/testing/sysfs-driver-xen-blkback  | 2 +-
>  Documentation/ABI/testing/sysfs-driver-xen-blkfront | 2 +-
>  drivers/block/xen-blkback/xenbus.c                  | 9 +++------
>  drivers/block/xen-blkfront.c                        | 4 +---
>  4 files changed, 6 insertions(+), 11 deletions(-)
> 
> -- 
> 2.25.1