From 97ec8c067d322d32effdc1701760d3babbc5595f Mon Sep 17 00:00:00 2001 From: Feng Wu Date: Tue, 1 Apr 2014 17:46:34 +0800 Subject: KVM: Add SMAP support when setting CR4 This patch adds SMAP handling logic when setting CR4 for guests Thanks a lot to Paolo Bonzini for his suggestion to use the branchless way to detect SMAP violation. Signed-off-by: Feng Wu Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/x86.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d1c55f8722c6..41693787cd66 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -652,6 +652,9 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) if (!guest_cpuid_has_smep(vcpu) && (cr4 & X86_CR4_SMEP)) return 1; + if (!guest_cpuid_has_smap(vcpu) && (cr4 & X86_CR4_SMAP)) + return 1; + if (!guest_cpuid_has_fsgsbase(vcpu) && (cr4 & X86_CR4_FSGSBASE)) return 1; @@ -680,6 +683,9 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) (!(cr4 & X86_CR4_PCIDE) && (old_cr4 & X86_CR4_PCIDE))) kvm_mmu_reset_context(vcpu); + if ((cr4 ^ old_cr4) & X86_CR4_SMAP) + update_permission_bitmask(vcpu, vcpu->arch.walk_mmu, false); + if ((cr4 ^ old_cr4) & X86_CR4_OSXSAVE) kvm_update_cpuid(vcpu); @@ -4164,7 +4170,8 @@ static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva, | (write ? PFERR_WRITE_MASK : 0); if (vcpu_match_mmio_gva(vcpu, gva) - && !permission_fault(vcpu->arch.walk_mmu, vcpu->arch.access, access)) { + && !permission_fault(vcpu, vcpu->arch.walk_mmu, + vcpu->arch.access, access)) { *gpa = vcpu->arch.mmio_gfn << PAGE_SHIFT | (gva & (PAGE_SIZE - 1)); trace_vcpu_match_mmio(gva, *gpa, write, false); -- cgit From b351c39cc9e0151cee9b8d52a1e714928faabb38 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Thu, 10 Apr 2014 18:19:12 -0300 Subject: KVM: x86: remove WARN_ON from get_kernel_ns() Function and callers can be preempted. https://bugzilla.kernel.org/show_bug.cgi?id=73721 Signed-off-by: Marcelo Tosatti Reviewed-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 41693787cd66..757d40871b30 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1123,7 +1123,6 @@ static inline u64 get_kernel_ns(void) { struct timespec ts; - WARN_ON(preemptible()); ktime_get_ts(&ts); monotonic_to_bootbased(&ts); return timespec_to_ns(&ts); -- cgit