Re: [PATCH v2 0/2] Emulated AMD IOMMU cleanup and fixes

[Vasant Hegde]

Hi Michael,


On 2/25/2025 2:17 PM, Michael Tokarev wrote:
> 07.02.2025 07:53, Sairaj Kodilkar wrote:
>> This series provides few bug fixes for emulated AMD IOMMU. The series is 
>> based
>> on top of qemu upstream master commit d922088eb4ba.
>>
>> Patch 1: The code was using wrong DTE field to determine interrupt 
>> passthrough.
>>           Hence replaced it with correct field according to [1].
>>
>> Patch 2: Current code sets the PCI capability BAR low and high to the
>>           lower and upper 16 bits of AMDVI_BASE_ADDR respectively, which is
>>           wrong. Instead use 32 bit mask to set the PCI capability BAR low 
>> and
>>           high.
>>           The guest IOMMU driver works with current qemu code because it uses
>>           base address from the IVRS table and not the one provided by
>>           PCI capability.
>>
>> Sairaj Kodilkar (2):
>>    amd_iommu: Use correct DTE field for interrupt passthrough
>>    amd_iommu: Use correct bitmask to set capability BAR
>>
>>   hw/i386/amd_iommu.c | 10 +++++-----
>>   hw/i386/amd_iommu.h |  2 +-
>>   2 files changed, 6 insertions(+), 6 deletions(-)
> 
> Is this qemu-stable material (current series: 7.2, 8.2, 9.2)?

Linux kernel doesn't use these changes. So its fine. But I believe we care for
other OS as well? if yes then better to backport.

> 
> 3684717b74 "amd_iommu: Use correct bitmask to set capability BAR" does
> not apply to 7.2, since v8.0.0-10-g6291a28645 "hw/i386/amd_iommu: Explicit
> use of AMDVI_BASE_ADDR in amdvi_init" in not in 7.2, but the change can be
> adjusted for 7.2 easily, or 6291a28645 can be picked up too.

How is this works? You will pick it up -OR- you want us to backport and send it
to stable mailing list?

-Vasant