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> + if (WARN_ON_ONCE(!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))) + return -EINVAL; > > iommu->ga_log = iommu_alloc_pages(GFP_KERNEL, get_order(GA_LOG_SIZE)); > if (!iommu->ga_log) > @@ -2863,8 +2863,10 @@ static void enable_iommus_vapic(void) > return; > } > > - if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) && > - !check_feature(FEATURE_GAM_VAPIC)) { > + if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir)) > + return; > + We should move this down after SNP check. Otherwise we may hit WARN_ON_ONCE in iommu_init_ga_log(). -Vasant > + if (!check_feature(FEATURE_GAM_VAPIC)) { > amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA; > return; > } > > base-commit: ea9bd29a9c0d757b3384ae3e633e6bbaddf00725