linux-kernel - [PATCH v2 3/3] x86/virt: Fold __cpu_emergency

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Date:   Wed, 18 May 2022 00:16:47 +0000
From:   Sean Christopherson <seanjc@...gle.com>
To:     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
Cc:     "H. Peter Anvin" <hpa@...or.com>, linux-kernel@...r.kernel.org,
        "Guilherme G . Piccoli" <gpiccoli@...lia.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <seanjc@...gle.com>
Subject: [PATCH v2 3/3] x86/virt: Fold __cpu_emergency_vmxoff() into its sole caller

Fold __cpu_emergency_vmxoff() into cpu_emergency_vmxoff(), its sole
remaining caller, to discourage crash/emergency code from handling VMX
but not SVM.  The behavior of VMX and SVM is so similar that it's highly
unlikely that there will be a scenario where VMX needs to be disabled,
but SVM can be left enabled.  In other words, during a crash and/or
emergency reboot, funnel all virtualization teardown sequences through
cpu_crash_disable_virtualization().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/include/asm/virtext.h | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h
index 8757078d4442..a9414ef5269e 100644
--- a/arch/x86/include/asm/virtext.h
+++ b/arch/x86/include/asm/virtext.h
@@ -60,22 +60,12 @@ static inline int cpu_vmx_enabled(void)
 	return __read_cr4() & X86_CR4_VMXE;
 }
 
-/** Disable VMX if it is enabled on the current CPU
- *
- * You shouldn't call this if cpu_has_vmx() returns 0.
- */
-static inline void __cpu_emergency_vmxoff(void)
-{
-	if (cpu_vmx_enabled())
-		cpu_vmxoff();
-}
-
 /** Disable VMX if it is supported and enabled on the current CPU
  */
 static inline void cpu_emergency_vmxoff(void)
 {
-	if (cpu_has_vmx())
-		__cpu_emergency_vmxoff();
+	if (cpu_has_vmx() && cpu_vmx_enabled())
+		cpu_vmxoff();
 }
 
 
-- 
2.36.0.550.gb090851708-goog