Re: [PATCH] iommu: amd: Fix IOMMU perf counter clobbering during init

[Suravee Suthikulpanit]

On 1/17/2020 5:08 PM, Joerg Roedel wrote:
> Adding Suravee, who wrote the IOMMU Perf Counter code.
>
> On Tue, Jan 14, 2020 at 08:12:20AM -0700, Shuah Khan wrote:
> > init_iommu_perf_ctr() clobbers the register when it checks write access
> > to IOMMU perf counters and fails to restore when they are writable.
> >
> > Add save and restore to fix it.
> >
> > Signed-off-by: Shuah Khan<skhan@xxxxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/iommu/amd_iommu_init.c | 22 ++++++++++++++++------
> >   1 file changed, 16 insertions(+), 6 deletions(-)
> Suravee, can you please review this patch?

This looks ok. Does this fix certain issues? Or is this just for sanity.

Reviewed-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>

Thanks,
Suravee