XCOMP_BV[63] field indicates that the save area is in the compacted
format and XCOMP_BV[62:0] indicates the states that have space allocated
in the save area, including both XCR0 and XSS bits enabled by the host
kernel. Use xfeatures_mask_all for calculating xcomp_bv and reuse
XCOMP_BV_COMPACTED_FORMAT defined by kernel.

Signed-off-by: Jing Liu <jing2....@linux.intel.com>
---
 arch/x86/kvm/x86.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1b404e4d7dd8..f115493f577d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4435,8 +4435,6 @@ static int kvm_vcpu_ioctl_x86_set_debugregs(struct 
kvm_vcpu *vcpu,
        return 0;
 }
 
-#define XSTATE_COMPACTION_ENABLED (1ULL << 63)
-
 static void fill_xsave(u8 *dest, struct kvm_vcpu *vcpu)
 {
        struct xregs_state *xsave = &vcpu->arch.guest_fpu->state.xsave;
@@ -4494,7 +4492,8 @@ static void load_xsave(struct kvm_vcpu *vcpu, u8 *src)
        /* Set XSTATE_BV and possibly XCOMP_BV.  */
        xsave->header.xfeatures = xstate_bv;
        if (boot_cpu_has(X86_FEATURE_XSAVES))
-               xsave->header.xcomp_bv = host_xcr0 | XSTATE_COMPACTION_ENABLED;
+               xsave->header.xcomp_bv = XCOMP_BV_COMPACTED_FORMAT |
+                                        xfeatures_mask_all;
 
        /*
         * Copy each region from the non-compacted offset to the
@@ -9912,9 +9911,6 @@ static void fx_init(struct kvm_vcpu *vcpu)
                return;
 
        fpstate_init(&vcpu->arch.guest_fpu->state);
-       if (boot_cpu_has(X86_FEATURE_XSAVES))
-               vcpu->arch.guest_fpu->state.xsave.header.xcomp_bv =
-                       host_xcr0 | XSTATE_COMPACTION_ENABLED;
 
        /*
         * Ensure guest xcr0 is valid for loading
-- 
2.18.4

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