[PATCH v2 16/18] x86/virt: KVM: Move "disable SVM" helper into KVM SVM

From: Sean Christopherson
Date: Fri Mar 10 2023 - 16:45:11 EST


Move cpu_svm_disable() into KVM proper now that all hardware
virtualization management is routed through KVM. Remove the now-empty
virtext.h.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/include/asm/virtext.h | 50 ----------------------------------
arch/x86/kvm/svm/svm.c | 28 +++++++++++++++++--
2 files changed, 25 insertions(+), 53 deletions(-)
delete mode 100644 arch/x86/include/asm/virtext.h

diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h
deleted file mode 100644
index 632575e257d8..000000000000
--- a/arch/x86/include/asm/virtext.h
+++ /dev/null
@@ -1,50 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/* CPU virtualization extensions handling
- *
- * This should carry the code for handling CPU virtualization extensions
- * that needs to live in the kernel core.
- *
- * Author: Eduardo Habkost <ehabkost@xxxxxxxxxx>
- *
- * Copyright (C) 2008, Red Hat Inc.
- *
- * Contains code from KVM, Copyright (C) 2006 Qumranet, Inc.
- */
-#ifndef _ASM_X86_VIRTEX_H
-#define _ASM_X86_VIRTEX_H
-
-#include <asm/processor.h>
-
-#include <asm/vmx.h>
-#include <asm/svm.h>
-#include <asm/tlbflush.h>
-
-/*
- * SVM functions:
- */
-/** Disable SVM on the current CPU
- */
-static inline void cpu_svm_disable(void)
-{
- uint64_t efer;
-
- wrmsrl(MSR_VM_HSAVE_PA, 0);
- rdmsrl(MSR_EFER, efer);
- if (efer & EFER_SVME) {
- /*
- * Force GIF=1 prior to disabling SVM to ensure INIT and NMI
- * aren't blocked, e.g. if a fatal error occurred between CLGI
- * and STGI. Note, STGI may #UD if SVM is disabled from NMI
- * context between reading EFER and executing STGI. In that
- * case, GIF must already be set, otherwise the NMI would have
- * been blocked, so just eat the fault.
- */
- asm_volatile_goto("1: stgi\n\t"
- _ASM_EXTABLE(1b, %l[fault])
- ::: "memory" : fault);
-fault:
- wrmsrl(MSR_EFER, efer & ~EFER_SVME);
- }
-}
-
-#endif /* _ASM_X86_VIRTEX_H */
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index f04b61c3d9d8..2db03991dcdf 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -41,7 +41,6 @@
#include <asm/reboot.h>
#include <asm/fpu/api.h>

-#include <asm/virtext.h>
#include "trace.h"

#include "svm.h"
@@ -584,9 +583,32 @@ void __svm_write_tsc_multiplier(u64 multiplier)
preempt_enable();
}

+static inline void kvm_cpu_svm_disable(void)
+{
+ uint64_t efer;
+
+ wrmsrl(MSR_VM_HSAVE_PA, 0);
+ rdmsrl(MSR_EFER, efer);
+ if (efer & EFER_SVME) {
+ /*
+ * Force GIF=1 prior to disabling SVM to ensure INIT and NMI
+ * aren't blocked, e.g. if a fatal error occurred between CLGI
+ * and STGI. Note, STGI may #UD if SVM is disabled from NMI
+ * context between reading EFER and executing STGI. In that
+ * case, GIF must already be set, otherwise the NMI would have
+ * been blocked, so just eat the fault.
+ */
+ asm_volatile_goto("1: stgi\n\t"
+ _ASM_EXTABLE(1b, %l[fault])
+ ::: "memory" : fault);
+fault:
+ wrmsrl(MSR_EFER, efer & ~EFER_SVME);
+ }
+}
+
static void svm_emergency_disable(void)
{
- cpu_svm_disable();
+ kvm_cpu_svm_disable();
}

static void svm_hardware_disable(void)
@@ -595,7 +617,7 @@ static void svm_hardware_disable(void)
if (tsc_scaling)
__svm_write_tsc_multiplier(SVM_TSC_RATIO_DEFAULT);

- cpu_svm_disable();
+ kvm_cpu_svm_disable();

amd_pmu_disable_virt();
}
--
2.40.0.rc1.284.g88254d51c5-goog