3.16.49-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jim Mattson <jmattson@xxxxxxxxxx> commit 4531662d1abf6c1f0e5c2b86ddb60e61509786c8 upstream. Bits 11:2 must be zero and the linear addess in bits 63:12 must be canonical. Otherwise, WRMSR(BNDCFGS) should raise #GP. Fixes: 0dd376e709975779 ("KVM: x86: add MSR_IA32_BNDCFGS to msrs_to_save") Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx> Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx> [bwh: Backported to 3.16: adjust filename, context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- arch/x86/include/uapi/asm/msr-index.h | 2 ++ arch/x86/kvm/vmx.c | 3 +++ 2 files changed, 5 insertions(+) --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -298,6 +298,8 @@ #define MSR_IA32_TSC_ADJUST 0x0000003b #define MSR_IA32_BNDCFGS 0x00000d90 +#define MSR_IA32_BNDCFGS_RSVD 0x00000ffc + #define FEATURE_CONTROL_LOCKED (1<<0) #define FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX (1<<1) #define FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX (1<<2) --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2589,6 +2589,9 @@ static int vmx_set_msr(struct kvm_vcpu * case MSR_IA32_BNDCFGS: if (!vmx_mpx_supported() || !guest_cpuid_has_mpx(vcpu)) return 1; + if (is_noncanonical_address(data & PAGE_MASK) || + (data & MSR_IA32_BNDCFGS_RSVD)) + return 1; vmcs_write64(GUEST_BNDCFGS, data); break; case MSR_IA32_TSC: