From: Jim Mattson <jmattson@google.com>
Date: Fri, 11 Oct 2024 21:43:52 +0000 (-0700)
Subject: KVM: x86: Advertise AMD_IBPB_RET to userspace
X-Git-Tag: v6.13-rc1~97^2~10^2~28
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=71dd5d5300d228fbfd816a620250a62bfacdd902;p=thirdparty%2Flinux.git

KVM: x86: Advertise AMD_IBPB_RET to userspace

This is an inherent feature of IA32_PRED_CMD[0], so it is trivially
virtualizable (as long as IA32_PRED_CMD[0] is virtualized).

Suggested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20241011214353.1625057-4-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
---

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 41786b834b163..53112669be002 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -755,7 +755,7 @@ void kvm_set_cpu_caps(void)
 		F(CLZERO) | F(XSAVEERPTR) |
 		F(WBNOINVD) | F(AMD_IBPB) | F(AMD_IBRS) | F(AMD_SSBD) | F(VIRT_SSBD) |
 		F(AMD_SSB_NO) | F(AMD_STIBP) | F(AMD_STIBP_ALWAYS_ON) |
-		F(AMD_PSFD)
+		F(AMD_PSFD) | F(AMD_IBPB_RET)
 	);
 
 	/*