[ Upstream commit 74cdc836919bf34684ef66f995273f35e2189daf ]
Make use of the kvm_read_cr{0,4}_bits() helper functions when we only want to know the state of certain bits instead of the whole register.
This not only makes the intent cleaner, it also avoids a potential VMREAD in case the tested bits aren't guest owned.
Signed-off-by: Mathias Krause minipli@grsecurity.net Link: https://lore.kernel.org/r/20230322013731.102955-5-minipli@grsecurity.net Signed-off-by: Sean Christopherson seanjc@google.com Signed-off-by: Mathias Krause minipli@grsecurity.net # backport to v5.15.x --- arch/x86/kvm/pmu.c | 4 ++-- arch/x86/kvm/vmx/vmx.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index 62333f9756a3..5c2b9ff8e014 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -366,9 +366,9 @@ int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned idx, u64 *data) if (!pmc) return 1;
- if (!(kvm_read_cr4(vcpu) & X86_CR4_PCE) && + if (!(kvm_read_cr4_bits(vcpu, X86_CR4_PCE)) && (static_call(kvm_x86_get_cpl)(vcpu) != 0) && - (kvm_read_cr0(vcpu) & X86_CR0_PE)) + (kvm_read_cr0_bits(vcpu, X86_CR0_PE))) return 1;
*data = pmc_read_counter(pmc) & mask; diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index c95c3675e8d5..566367409598 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5128,7 +5128,7 @@ static int handle_cr(struct kvm_vcpu *vcpu) break; case 3: /* lmsw */ val = (exit_qualification >> LMSW_SOURCE_DATA_SHIFT) & 0x0f; - trace_kvm_cr_write(0, (kvm_read_cr0(vcpu) & ~0xful) | val); + trace_kvm_cr_write(0, (kvm_read_cr0_bits(vcpu, ~0xful) | val)); kvm_lmsw(vcpu, val);
return kvm_skip_emulated_instruction(vcpu); @@ -7149,7 +7149,7 @@ static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) goto exit; }
- if (kvm_read_cr0(vcpu) & X86_CR0_CD) { + if (kvm_read_cr0_bits(vcpu, X86_CR0_CD)) { ipat = VMX_EPT_IPAT_BIT; if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED)) cache = MTRR_TYPE_WRBACK;