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Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > On Mon, 20 Apr 2026 08:42:02 +0000 Vasant Hegde 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. Do you have dmesg? > > 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. > > Could you help in fixing this issue? Sure. We will try to reproduce it internally and get back to you. -Vasant