Re: [PATCH] iommu/amd: Do not reallocate GA log buffers on resume

[Vasant Hegde <vasant.hegde@amd.com>]

On 8/19/2026 8:53 AM, Karl Mehltretter wrote:
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> 
> Commit c5e1a1eb9279 ("iommu/amd: Simplify and Consolidate Virtual APIC
> (AVIC) Enablement") moved the GA log allocation from iommu_init_pci()
> to enable_iommus_vapic(), which is called on every resume.
> 
> iommu_init_ga_log() assigns iommu->ga_log and iommu->ga_log_tail
> unconditionally. Each resume therefore replaces the boot-time pointers
> and leaks both old allocations. The function also uses GFP_KERNEL from a
> syscore resume callback, where interrupts are disabled and the non-boot
> CPUs are offline.
> 
> Return early if both buffers are already allocated. Clear the pointers
> in free_ga_log() so a partial allocation failure cannot leave ga_log
> dangling.
> 
> Fixes: c5e1a1eb9279 ("iommu/amd: Simplify and Consolidate Virtual APIC (AVIC) Enablement")
> Assisted-by: Claude:claude-opus-5
> Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>

Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>

@Joerg, I think we should pick this for -rc.

-Vasant