linux-kernel - [PATCH 6/9] KVM: VMX: simplify invpcid handling in vmx_cpuid

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: <1440132611-26052-7-git-send-email-guangrong.xiao@linux.intel.com>
Date:	Fri, 21 Aug 2015 12:50:08 +0800
From:	Xiao Guangrong <guangrong.xiao@...ux.intel.com>
To:	pbonzini@...hat.com
Cc:	gleb@...nel.org, mtosatti@...hat.com, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Xiao Guangrong <guangrong.xiao@...ux.intel.com>
Subject: [PATCH 6/9] KVM: VMX: simplify invpcid handling in vmx_cpuid_update()

If vmx_invpcid_supported() is true, second execution control
filed must be supported and SECONDARY_EXEC_ENABLE_INVPCID
must have already been set in current vmcs by
vmx_secondary_exec_control()

If vmx_invpcid_supported() is false, no need to clear
SECONDARY_EXEC_ENABLE_INVPCID

Signed-off-by: Xiao Guangrong <guangrong.xiao@...ux.intel.com>
---
 arch/x86/kvm/vmx.c | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 99f638e..0d68140 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8684,20 +8684,13 @@ static void vmx_cpuid_update(struct kvm_vcpu *vcpu)
 
 	/* Exposing INVPCID only when PCID is exposed */
 	best = kvm_find_cpuid_entry(vcpu, 0x7, 0);
-	if (vmx_invpcid_supported() &&
-	    best && (best->ebx & bit(X86_FEATURE_INVPCID)) &&
-	    guest_cpuid_has_pcid(vcpu)) {
+	if (vmx_invpcid_supported() && (!best ||
+	    !(best->ebx & bit(X86_FEATURE_INVPCID)) ||
+	    !guest_cpuid_has_pcid(vcpu))) {
 		exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL);
-		exec_control |= SECONDARY_EXEC_ENABLE_INVPCID;
-		vmcs_write32(SECONDARY_VM_EXEC_CONTROL,
-			     exec_control);
-	} else {
-		if (cpu_has_secondary_exec_ctrls()) {
-			exec_control = vmcs_read32(SECONDARY_VM_EXEC_CONTROL);
-			exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID;
-			vmcs_write32(SECONDARY_VM_EXEC_CONTROL,
-				     exec_control);
-		}
+		exec_control &= ~SECONDARY_EXEC_ENABLE_INVPCID;
+		vmcs_write32(SECONDARY_VM_EXEC_CONTROL, exec_control);
+
 		if (best)
 			best->ebx &= ~bit(X86_FEATURE_INVPCID);
 	}
-- 
2.4.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/