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authorPaolo Bonzini <pbonzini@redhat.com>2014-02-24 12:15:16 +0100
committerPaolo Bonzini <pbonzini@redhat.com>2014-03-17 12:21:38 +0100
commit4ff417320c2dfc984ec1939a7da888976441a881 (patch)
tree3448c4e65aecd71260c9bbe4e99c70533c6055e9 /arch/x86/kvm/x86.h
parent94b3ffcd41a90d2cb0b32ca23aa58a01111d5dc0 (diff)
downloadlinux-4ff417320c2dfc984ec1939a7da888976441a881.tar.bz2
KVM: x86: introduce kvm_supported_xcr0()
XSAVE support for KVM is already using host_xcr0 & KVM_SUPPORTED_XCR0 as a "dynamic" version of KVM_SUPPORTED_XCR0. However, this is not enough because the MPX bits should not be presented to the guest unless kvm_x86_ops confirms the support. So, replace all instances of host_xcr0 & KVM_SUPPORTED_XCR0 with a new function kvm_supported_xcr0() that also has this check. Note that here: if (xstate_bv & ~KVM_SUPPORTED_XCR0) return -EINVAL; if (xstate_bv & ~host_cr0) return -EINVAL; the code is equivalent to if ((xstate_bv & ~KVM_SUPPORTED_XCR0) || (xstate_bv & ~host_cr0) return -EINVAL; i.e. "xstate_bv & (~KVM_SUPPORTED_XCR0 | ~host_cr0)" which is in turn equal to "xstate_bv & ~(KVM_SUPPORTED_XCR0 & host_cr0)". So we should also use the new function there. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/x86.h')
-rw-r--r--arch/x86/kvm/x86.h2
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 392ecbff0030..8c97bac9a895 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -126,6 +126,8 @@ int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt,
| XSTATE_BNDREGS | XSTATE_BNDCSR)
extern u64 host_xcr0;
+extern u64 kvm_supported_xcr0(void);
+
extern unsigned int min_timer_period_us;
extern struct static_key kvm_no_apic_vcpu;