linux-kernel - [RFC PATCH 04/18] KVM: VMX: add cpu_has_vmx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250313203702.575156-5-jon@nutanix.com>
Date: Thu, 13 Mar 2025 13:36:43 -0700
From: Jon Kohler <jon@...anix.com>
To: seanjc@...gle.com, pbonzini@...hat.com, tglx@...utronix.de,
        mingo@...hat.com, bp@...en8.de, dave.hansen@...ux.intel.com,
        x86@...nel.org, hpa@...or.com, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc: Mickaël Salaün <mic@...ikod.net>,
        Jon Kohler <jon@...anix.com>
Subject: [RFC PATCH 04/18] KVM: VMX: add cpu_has_vmx_mbec helper

From: Mickaël Salaün <mic@...ikod.net>

Add 'cpu_has_vmx_mbec' helper to determine whether the cpu based VMCS
from hardware has Intel Mode Based Execution Control exposed, which is
secondary execution control bit 22.

Signed-off-by: Mickaël Salaün <mic@...ikod.net>
Co-developed-by: Jon Kohler <jon@...anix.com>
Signed-off-by: Jon Kohler <jon@...anix.com>

---
 arch/x86/kvm/vmx/capabilities.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index cb6588238f46..f83592272920 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -253,6 +253,12 @@ static inline bool cpu_has_vmx_xsaves(void)
 		SECONDARY_EXEC_ENABLE_XSAVES;
 }
 
+static inline bool cpu_has_vmx_mbec(void)
+{
+	return vmcs_config.cpu_based_2nd_exec_ctrl &
+		SECONDARY_EXEC_MODE_BASED_EPT_EXEC;
+}
+
 static inline bool cpu_has_vmx_waitpkg(void)
 {
 	return vmcs_config.cpu_based_2nd_exec_ctrl &
-- 
2.43.0