linux-kernel - [PATCH 2/2] KVM: nVMX: remove unnecessary CR4_READ

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]

Date: Tue, 16 Apr 2024 14:35:57 +0200
From: Julian Stecklina <julian.stecklina@...erus-technology.de>
To: Sean Christopherson <seanjc@...gle.com>,
	Paolo Bonzini <pbonzini@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	x86@...nel.org,
	"H. Peter Anvin" <hpa@...or.com>
Cc: Thomas Prescher <thomas.prescher@...erus-technology.de>,
	Julian Stecklina <julian.stecklina@...erus-technology.de>,
	kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] KVM: nVMX: remove unnecessary CR4_READ_SHADOW write

From: Thomas Prescher <thomas.prescher@...erus-technology.de>

This explicit change of CR4_READ_SHADOW is no longer necessary because
it is now handled in vmx_set_cr4.

Signed-off-by: Julian Stecklina <julian.stecklina@...erus-technology.de>
Signed-off-by: Thomas Prescher <thomas.prescher@...erus-technology.de>
---
 arch/x86/kvm/vmx/nested.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index d05ddf751491..e191bf5d4831 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -2639,7 +2639,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
 	vmcs_writel(CR0_READ_SHADOW, nested_read_cr0(vmcs12));
 
 	vmx_set_cr4(vcpu, vmcs12->guest_cr4);
-	vmcs_writel(CR4_READ_SHADOW, nested_read_cr4(vmcs12));
 
 	vcpu->arch.efer = nested_vmx_calc_efer(vmx, vmcs12);
 	/* Note: may modify VM_ENTRY/EXIT_CONTROLS and GUEST/HOST_IA32_EFER */
-- 
2.43.2