mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Sean Christopherson <seanjc@google.com>
To: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	x86@kernel.org, Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>,
	linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Subject: [PATCH 3/3] KVM: VMX: Drop manual checks on X86_FEATURE_MSR_IA32_FEAT_CTL
Date: Sat,  3 Dec 2022 00:37:45 +0000	[thread overview]
Message-ID: <20221203003745.1475584-4-seanjc@google.com> (raw)
In-Reply-To: <20221203003745.1475584-1-seanjc@google.com>

Drop manual checks on X86_FEATURE_MSR_IA32_FEAT_CTL and instead rely
solely on the X86_FEATURE_VMX check to detect VMX support now that VMX is
disabled via apply_cpuid_deps() if X86_FEATURE_MSR_IA32_FEAT_CTL isn't
supported.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kernel/cpu/bugs.c | 3 +--
 arch/x86/kvm/vmx/vmx.c     | 6 ++----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 9e84b685328f..3071e2a97f0d 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -2222,8 +2222,7 @@ static ssize_t l1tf_show_state(char *buf)
 
 static ssize_t itlb_multihit_show_state(char *buf)
 {
-	if (!boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
-	    !boot_cpu_has(X86_FEATURE_VMX))
+	if (!boot_cpu_has(X86_FEATURE_VMX))
 		return sysfs_emit(buf, "KVM: Mitigation: VMX unsupported\n");
 	else if (!(cr4_read_shadow() & X86_CR4_VMXE))
 		return sysfs_emit(buf, "KVM: Mitigation: VMX disabled\n");
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 9dba04b6b019..de3fe3932ee8 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2423,8 +2423,7 @@ static __init int cpu_has_kvm_support(void)
 
 static __init int vmx_disabled_by_bios(void)
 {
-	return !boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
-	       !boot_cpu_has(X86_FEATURE_VMX);
+	return !boot_cpu_has(X86_FEATURE_VMX);
 }
 
 static int kvm_cpu_vmxon(u64 vmxon_pointer)
@@ -7413,8 +7412,7 @@ static int __init vmx_check_processor_compat(void)
 	struct vmcs_config vmcs_conf;
 	struct vmx_capability vmx_cap;
 
-	if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
-	    !this_cpu_has(X86_FEATURE_VMX)) {
+	if (!this_cpu_has(X86_FEATURE_VMX)) {
 		pr_err("kvm: VMX is disabled on CPU %d\n", smp_processor_id());
 		return -EIO;
 	}
-- 
2.39.0.rc0.267.gcb52ba06e7-goog


      parent reply	other threads:[~2022-12-03  0:40 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-03  0:37 [PATCH 0/3] x86/cpu: KVM: Make SGX and VMX depend on FEAT_CTL Sean Christopherson
2022-12-03  0:37 ` [PATCH 1/3] x86/cpu: Process all CPUID dependencies after identifying CPU info Sean Christopherson
2022-12-08 16:14   ` Borislav Petkov
2022-12-08 16:26     ` Sean Christopherson
2022-12-08 16:45       ` Borislav Petkov
2023-01-04 21:02         ` Sean Christopherson
2023-01-04 22:55           ` Borislav Petkov
2023-01-04 23:18             ` Sean Christopherson
2023-01-05 10:15               ` Borislav Petkov
2022-12-03  0:37 ` [PATCH 2/3] x86/cpu: Mark SGX and VMX as being dependent on MSR_IA32_FEAT_CTL Sean Christopherson
2022-12-03  0:37 ` Sean Christopherson [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20221203003745.1475584-4-seanjc@google.com \
    --to=seanjc@google.com \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®