Re: [PATCH 0/2] iommu/amd: Use MAX buffer size when SNP is enabled on Family 0x19

[Usama Arif <usama.arif@linux.dev>]

On 13/08/2026 14:35, Jason Gunthorpe wrote:
> On Thu, Aug 13, 2026 at 06:18:30AM -0700, Usama Arif wrote:
>> On Mon, 20 Apr 2026 08:42:02 +0000 Vasant Hegde <vasant.hegde@amd.com> wrote:
>>
>>> This series addresses CVE-2023-20585 [1] by increasing the AMD IOMMU
>>> Event log and PPR log buffer sizes to the maximum supported value (512K)
>>> on affected CPU families when SNP is enabled.
>>>
>>> Use MAX buffer size when SNP is enabled on Milan/Genoa. Impacted buffers:
>>>   - Milan : Event log (PPR/GALog is not supported when SNP is enabled)
>>>   - Genoa : Event and PPR log (GALog is not supported when SNP is enabled)
>>>
>>
>> Hi,
>>
>> This series seems to break kexec in our production on Milan hosts with SEV enabled.
>> This is on the 6.18.43 stable kernel backport.
>>
>> If on top of 6.18.43 release, we revert the 2 commits, i.e.
>> Revert "iommu/amd: Use maximum PPR log buffer size when SNP is enabled on Family 0x19"
>> Revert "iommu/amd: Use maximum Event log buffer size when SNP is enabled on Family 0x19"
>>
>> kexec starts working again.
> 
> This sounds like the same issue Nicolin is facing on SMMUv3, these
> larger allocations OOM the kexec kernel
> 
> Jason

Thanks Jason!

Was there any solution for this issue. Could you point to a lore link for this?