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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2025 15:20:31.6942 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: a7a02269-8e61-4e23-a718-08dde3eaee5c X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN3PEPF0000B06B.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5963 When HvInUseWrAllowed (CPUID 8000001F EAX[30]) is supported, the CPU allows hypervisor writes to in-use pages without RMP violations, making the 2MB alignment workaround unnecessary. Check for this capability to avoid the allocation overhead when it's not needed. Suggested-by: Tom Lendacky Signed-off-by: Nikunj A Dadhania --- arch/x86/kvm/svm/sev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 2fbdebf79fbb..c5477efc90b9 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -4666,7 +4666,8 @@ struct page *snp_safe_alloc_page_node(int node, gfp_t gfp) unsigned long pfn; struct page *p; - if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP)) + if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP) || + cpu_feature_enabled(X86_FEATURE_HV_INUSE_WR_ALLOWED)) return alloc_pages_node(node, gfp | __GFP_ZERO, 0); /* -- 2.43.0