[PATCH v2 3/6] KVM: x86: introduce kvm_register_clear_available

From: Maxim Levitsky
Date: Mon Apr 26 2021 - 07:14:41 EST


Small refactoring that will be used in the next patch.

Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
arch/x86/kvm/kvm_cache_regs.h | 7 +++++++
arch/x86/kvm/svm/svm.c | 6 ++----
2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 3db5c42c9ecd..b8559b83c4ca 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -55,6 +55,13 @@ static inline void kvm_register_mark_available(struct kvm_vcpu *vcpu,
__set_bit(reg, (unsigned long *)&vcpu->arch.regs_avail);
}

+static inline void kvm_register_clear_available(struct kvm_vcpu *vcpu,
+ enum kvm_reg reg)
+{
+ __clear_bit(reg, (unsigned long *)&vcpu->arch.regs_avail);
+ __clear_bit(reg, (unsigned long *)&vcpu->arch.regs_dirty);
+}
+
static inline void kvm_register_mark_dirty(struct kvm_vcpu *vcpu,
enum kvm_reg reg)
{
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 14ff7f0963e9..c596bf1a4ae8 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3868,10 +3868,8 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
vcpu->arch.apf.host_apf_flags =
kvm_read_and_reset_apf_flags();

- if (npt_enabled) {
- vcpu->arch.regs_avail &= ~(1 << VCPU_EXREG_PDPTR);
- vcpu->arch.regs_dirty &= ~(1 << VCPU_EXREG_PDPTR);
- }
+ if (npt_enabled)
+ kvm_register_clear_available(vcpu, VCPU_EXREG_PDPTR);

/*
* We need to handle MC intercepts here before the vcpu has a chance to
--
2.26.2