KVM: x86: introduce ISA specific SMM entry/exit callbacks
Entering and exiting SMM may require ISA specific handling under certain
circumstances. This commit adds two new callbacks with empty implementations.
Actual functionality will be added in following commits.
* pre_enter_smm() is to be called when injecting an SMM, before any
SMM related vcpu state has been changed
* pre_leave_smm() is to be called when emulating the RSM instruction,
when the vcpu is in real mode and before any SMM related vcpu state
has been restored
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4ac2610..9e85a69 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5281,6 +5281,11 @@ static void emulator_set_hflags(struct x86_emulate_ctxt *ctxt, unsigned emul_fla
kvm_set_hflags(emul_to_vcpu(ctxt), emul_flags);
}
+static int emulator_pre_leave_smm(struct x86_emulate_ctxt *ctxt, u64 smbase)
+{
+ return kvm_x86_ops->pre_leave_smm(emul_to_vcpu(ctxt), smbase);
+}
+
static const struct x86_emulate_ops emulate_ops = {
.read_gpr = emulator_read_gpr,
.write_gpr = emulator_write_gpr,
@@ -5322,6 +5327,7 @@ static const struct x86_emulate_ops emulate_ops = {
.set_nmi_mask = emulator_set_nmi_mask,
.get_hflags = emulator_get_hflags,
.set_hflags = emulator_set_hflags,
+ .pre_leave_smm = emulator_pre_leave_smm,
};
static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask)
@@ -6647,13 +6653,20 @@ static void enter_smm(struct kvm_vcpu *vcpu)
u32 cr0;
trace_kvm_enter_smm(vcpu->vcpu_id, vcpu->arch.smbase, true);
- vcpu->arch.hflags |= HF_SMM_MASK;
memset(buf, 0, 512);
if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
enter_smm_save_state_64(vcpu, buf);
else
enter_smm_save_state_32(vcpu, buf);
+ /*
+ * Give pre_enter_smm() a chance to make ISA-specific changes to the
+ * vCPU state (e.g. leave guest mode) after we've saved the state into
+ * the SMM state-save area.
+ */
+ kvm_x86_ops->pre_enter_smm(vcpu, buf);
+
+ vcpu->arch.hflags |= HF_SMM_MASK;
kvm_vcpu_write_guest(vcpu, vcpu->arch.smbase + 0xfe00, buf, sizeof(buf));
if (kvm_x86_ops->get_nmi_mask(vcpu))