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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?D8k7PuGV99bM0c4oEpqjMkw0Q+r5kiG2Sc31S25omMo/58T1aUDYvelYZT1f?= =?us-ascii?Q?Ex4V1gbB7pqThtI1f956l4OANxFIF2el4oWFSG2Ebk/0lOGb2YJyoH+q3q0d?= =?us-ascii?Q?V+pLO5xQmKGWC78g52SJO0ZluwA9A8/4OW580+I8/VujM1ImpamZQz+LzNJ+?= =?us-ascii?Q?Urca2hkTfuJT8KJnjZ4jhGMKoS7votpv7rDhgbGvf4y9rG5xOF69/wle0wPC?= =?us-ascii?Q?JBZtwdLcbArJI26vswpnOaU65nN1pSD1+FJdVYY4LWdnLTaXiaUCVJ0AXiUF?= =?us-ascii?Q?7blXpd5aQWIg1q2NMK9gqVJdbyn5PD1etm/pL8ac8phLl0bPHFf7zLk6j6uu?= =?us-ascii?Q?kCkO79IElLw4MynRMl3DeOXCpfguE9Ft4+AOmuRUH8H4CoXXYSPI5GDy0FWi?= =?us-ascii?Q?nJ6WeguwAvbGSNGiOhe9jGpenA3FIlcbuCywW9Mdsh3u+UEo5ZqNm6aalC3m?= =?us-ascii?Q?CL3sb8PVSYF8z5uMa5EFmVpUFR2JhxJXZAzI5Coc4Qs0Y847QULA7R8p4RRk?= =?us-ascii?Q?taRZVRRxOovBeXSKhCLP01UTIVUlFPgcJrFdJaVw5sXFCumNjAVOoBJ3565k?= =?us-ascii?Q?lbm0TwGlRs2ljP3wNQAD9qR1nnYC1Y2Rpm3SAqr9gPxfBCD2JTrY/PzzEqpI?= =?us-ascii?Q?xCE7FijCkIdLknR1EaIXmvWOX5312fxorY6o5XMUzXTj08WKbdt0MSJWv1zV?= =?us-ascii?Q?eY3b7nXZ9qMP6caOrUu1q03NlectGXfKNWokKrEfyTk+FcUQHvLG/RrTeUiy?= =?us-ascii?Q?mNE4U6LRQQ3Pr+lWkL3vl1H4P8XVlAqswPZkQY6SjwadlBsorbZzpm8R79nt?= =?us-ascii?Q?lt+USl/CivNaoaYtcRd+16R69ci6RyAAl+ZR7sxpFHb88O6pcuh04Uz1IWRt?= =?us-ascii?Q?JArf04ma8X0eCVth7AZgybX0tUUitwmUmO5ceJPu7SaR2qfnHrmC0MdwQYv+?= =?us-ascii?Q?KaDMQKfKxYHx0IgHuTqhmotBSSuq50dJRlklJwQgoVnz+AQTtS3pMdKyytdf?= =?us-ascii?Q?UuN9BYMs4lmY15zCI2ft/B2U8ZESIoTzLL37qc6lzrrye0Vu8DCTv6D2Dv7T?= =?us-ascii?Q?PPEZwdpWdMR/XqVPwXMULBqQgUzXPJTIzhjyN+5ryBlFinglfwnPjMwngWWB?= =?us-ascii?Q?A6rtmB/324KlVRjgxgIWqCDODZpM5kUoh8WwYYU38mu5nHNycyoqWcoto+ZF?= =?us-ascii?Q?E73QbydYF4KvEMGPjRjKpm75Cwp6OAhPJPwTRVft4TDbah3Yd6j/kEeaqh6U?= =?us-ascii?Q?p0fYJe7PWsD/bhWT5cWyWGwh2VyR+ag7uRgSA2V5yibIjqEK+aFfRpIOlKLk?= =?us-ascii?Q?XIP5opu6/54PeEeUIeLA6qQQ1FNFMj6thlui/sBjOb5GhdvrY1zuCvS3MDkV?= =?us-ascii?Q?9ftonxj7jdNsytKZ3Q0MhB1JGQcKFwncHdC89COT7XfgMxAWB339HS730k9m?= =?us-ascii?Q?VsoLjtPEiQ4hkVbeIWpJ2L3wvhoe+mAd/UTM+inrDoDxlehNF/Uzezusf6NL?= =?us-ascii?Q?YLI2SdhCziroQ18Xbrws7lVcLsz8is3lqTKiZEv6ZwNfMa7jNHIOB6Snye7I?= =?us-ascii?Q?xzTikGIQXI5vwCl4Lam5Qa6tmVuCoXZduGVvHRzq?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3253c606-fbc0-4447-8e06-08ddeb2d1916 X-MS-Exchange-CrossTenant-AuthSource: BL1PR12MB5995.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Sep 2025 21:01:48.6255 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Sw0eXwQIeGCgwzUjmery05REdDUKaYvkNtQKSkH7gslhP1eB1vLXNWcjTVwQIO/lRtRhZRe/8iUFkW/Iz9USgg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB4323 On Mon, Aug 25, 2025 at 09:33:09AM +0800, Chao Gao wrote: > On Wed, Aug 06, 2025 at 08:45:10PM +0000, John Allen wrote: > >Remove the explicit clearing of shadow stack CPU capabilities. > > > >Signed-off-by: John Allen > >--- > >v3: > > - New in v3. > >--- > > arch/x86/kvm/svm/svm.c | 5 ----- > > 1 file changed, 5 deletions(-) > > > >diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > >index 82cde3578c96..b67aa546d8f4 100644 > >--- a/arch/x86/kvm/svm/svm.c > >+++ b/arch/x86/kvm/svm/svm.c > >@@ -5255,11 +5255,6 @@ static __init void svm_set_cpu_caps(void) > > kvm_set_cpu_caps(); > > > > kvm_caps.supported_perf_cap = 0; > >- kvm_caps.supported_xss = 0; > >- > >- /* KVM doesn't yet support CET virtualization for SVM. */ > >- kvm_cpu_cap_clear(X86_FEATURE_SHSTK); > >- kvm_cpu_cap_clear(X86_FEATURE_IBT); > > IIUC, IBT should be cleared because KVM doesn't support IBT for SVM. Yeah, I wondered about this. The reason I chose to not clear this is because we don't explicitly clear other features that are not supported on AMD hardware AFAICT. Is there a reason we should clear this and not other unsupported features? Thanks, John