Re: [PATCH 1/2] iommu/vt-d: Fix missing PASID in dev TLB flush with cache_tag_flush_all

[Ethan MILON <ethan.milon@eviden.com>]

Hi Baolu,

Thanks for the review.

On 7/10/25 10:59, Baolu Lu wrote:
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> 
> 
> On 7/9/2025 5:48 AM, Ethan MILON wrote:
>> The function cache_tag_flush_all() was originally implemented with
>> incorrect device TLB invalidation logic that does not handle PASID, in
>> commit c4d27ffaa8eb ("iommu/vt-d: Add cache tag invalidation helpers")
>>
>> This causes regressions where full address space TLB invalidations occur
>> with a PASID attached, such as during transparent hugepage unmapping in
>> SVA configurations or when calling iommu_flush_iotlb_all(). In these
>> cases, the device receives a TLB invalidation that lacks PASID.
>>
>> This incorrect logic was later extracted into
>> cache_tag_flush_devtlb_all(), in commit 3297d047cd7f ("iommu/vt-d:
>> Refactor IOTLB and Dev-IOTLB flush for batching")
>>
>> The fix replaces the call to cache_tag_flush_devtlb_all() with
>> cache_tag_flush_devtlb_psi(), which properly handles PASID.
>>
>> Fixes: 4f609dbff51b ("iommu/vt-d: Use cache helpers in arch_invalidate_secondary_tlbs")
>> Fixes: 4e589a53685c ("iommu/vt-d: Use cache_tag_flush_all() in flush_iotlb_all")
>>
> 
> Remove above blank line.

Noted.

> 
>> Signed-off-by: Ethan Milon<ethan.milon@eviden.com>
> 
> checkpatch.pl complains:
> 
> WARNING: From:/Signed-off-by: email name mismatch: 'From: Ethan MILON
> <ethan.milon@eviden.com>' != 'Signed-off-by: Ethan Milon
> <ethan.milon@eviden.com>'

Understood. Our email server seems to overwrite our last names. I’ll
look into correcting that.

> 
>> ---
>>   drivers/iommu/intel/cache.c | 18 +-----------------
>>   1 file changed, 1 insertion(+), 17 deletions(-)
> 
> Other looks good to me.

Should I send a v2 with the fixes?

Thanks,
Ethan

> 
> Thanks,
> baolu