Re: [PATCH 0/3] target/i386/cpu: Misc Cleanup on host-cache-info

[Zhao Liu]

Hi Igor,

Just a friendly ping :-)

May I ask if you are satisfied with the clarification in this series?

Thanks,
Zhao

On Mon, Jul 08, 2024 at 10:23:26AM +0800, Zhao Liu wrote:
> Date: Mon, 8 Jul 2024 10:23:26 +0800
> From: Zhao Liu <zhao1.liu@intel.com>
> Subject: Re: [PATCH 0/3] target/i386/cpu: Misc Cleanup on host-cache-info
> 
> Hi Igor,
> 
> Just a gentle poke and what do you think about this minor series?
> 
> Thanks,
> Zhao
> 
> On Wed, Jun 19, 2024 at 10:42:12PM +0800, Zhao Liu wrote:
> > Date: Wed, 19 Jun 2024 22:42:12 +0800
> > From: Zhao Liu <zhao1.liu@intel.com>
> > Subject: [PATCH 0/3] target/i386/cpu: Misc Cleanup on host-cache-info
> > X-Mailer: git-send-email 2.34.1
> > 
> > Hi,
> > 
> > This series is mainly to addresss Igor's comment about if one check in
> > host-cache-info could be removed [1], i.e., whether Guest's cache
> > topology should be self-consistent (able to correspond to Guest's CPU
> > topology level, as we currently do with the Guest cache topo).
> > 
> > I originally thought (in the mail thread with Igor) that host-cache-info
> > should allow Guest and Host to have the same topology level information,
> > e.g. if Host shares cache on core level, then via host-cache-info, Guest
> > should also share on core level.
> > 
> > But in practice, I gave up on this idea, because in the cache info
> > passthrough case, it should be possible for Guest to get the original
> > Host cache info (including the original threads sharing cache) without
> > further modifying the info to Guest.
> > 
> > Therefore, I simply added the comment in PATCH 3 to hopefully illustrate
> > the need for such a check.
> > 
> > Hope my explanation is clear enough so that my poor English doesn't
> > bother you!
> > 
> > [1]: 
> > https://lore.kernel.org/qemu-devel/20240527170317.14520a2f@imammedo.users.ipa.redhat.com/
> > 
> > Thanks and Best Regards,
> > Zhao
> > ---
> > Zhao Liu (3):
> >   target/i386/cpu: Use hex mask to check for valid cache CPUID leaf
> >   target/i386/cpu: Check guest_thread_ids_per_pkg for host-cache-info
> >     case
> >   target/i386/cpu: Add comment about adjusting the Guest cache topo for
> >     host-cache-info
> > 
> >  target/i386/cpu.c | 24 +++++++++++++++++++-----
> >  1 file changed, 19 insertions(+), 5 deletions(-)
> > 
> > -- 
> > 2.34.1
> > 
> > 
>