diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-02-04 17:24:57 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-02-09 08:17:05 -0500 |
| commit | 16d5163f338753fb93b1809e067da5d27d540fbc (patch) | |
| tree | 0b9deb681e2c29c6265dea3fd77f69f376fca411 /arch/x86/kvm/emulate.c | |
| parent | 448841f0b7b50f1b8d7a40138dfb0d882435c8bd (diff) | |
KVM: x86: Remove misleading DR6/DR7 adjustments from RSM emulation
Drop the DR6/7 volatile+fixed bits adjustments in RSM emulation, which
are redundant and misleading. The necessary adjustments are made by
kvm_set_dr(), which properly sets the fixed bits that are conditional
on the vCPU model.
Note, KVM incorrectly reads only bits 31:0 of the DR6/7 fields when
emulating RSM on x86-64. On the plus side for this change, that bug
makes removing "& DRx_VOLATILE" a nop.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210205012458.3872687-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/emulate.c')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 612ee691065f..b5f433d01caa 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2506,12 +2506,12 @@ static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt, val = GET_SMSTATE(u32, smstate, 0x7fcc); - if (ctxt->ops->set_dr(ctxt, 6, (val & DR6_VOLATILE) | DR6_FIXED_1)) + if (ctxt->ops->set_dr(ctxt, 6, val)) return X86EMUL_UNHANDLEABLE; val = GET_SMSTATE(u32, smstate, 0x7fc8); - if (ctxt->ops->set_dr(ctxt, 7, (val & DR7_VOLATILE) | DR7_FIXED_1)) + if (ctxt->ops->set_dr(ctxt, 7, val)) return X86EMUL_UNHANDLEABLE; selector = GET_SMSTATE(u32, smstate, 0x7fc4); @@ -2566,12 +2566,12 @@ static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt, val = GET_SMSTATE(u32, smstate, 0x7f68); - if (ctxt->ops->set_dr(ctxt, 6, (val & DR6_VOLATILE) | DR6_FIXED_1)) + if (ctxt->ops->set_dr(ctxt, 6, val)) return X86EMUL_UNHANDLEABLE; val = GET_SMSTATE(u32, smstate, 0x7f60); - if (ctxt->ops->set_dr(ctxt, 7, (val & DR7_VOLATILE) | DR7_FIXED_1)) + if (ctxt->ops->set_dr(ctxt, 7, val)) return X86EMUL_UNHANDLEABLE; cr0 = GET_SMSTATE(u64, smstate, 0x7f58); |