Commit be479419 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

Merge tag 'kvm-x86-svm-6.7' of https://github.com/kvm-x86/linux into HEAD 

KVM SVM changes for 6.7:

 - Report KVM_EXIT_SHUTDOWN instead of EINVAL if KVM intercepts SHUTDOWN while
   running an SEV-ES guest.

 - Clean up handling "failures" when KVM detects it can't emulate the "skip"
   action for an instruction that has already been partially emulated.  Drop a
   hack in the SVM code that was fudging around the emulator code not giving
   SVM enough information to do the right thing.
parents d5cde2e0 00682995

arch/x86/include/asm/kvm-x86-ops.h

+1 −1
Original line number Diff line number Diff line
@@ -127,7 +127,7 @@ KVM_X86_OP_OPTIONAL(vm_copy_enc_context_from) 
KVM_X86_OP_OPTIONAL(vm_move_enc_context_from)

KVM_X86_OP_OPTIONAL(guest_memory_reclaimed)

KVM_X86_OP(get_msr_feature)

KVM_X86_OP(can_emulate_instruction)

KVM_X86_OP(check_emulate_instruction)

KVM_X86_OP(apic_init_signal_blocked)

KVM_X86_OP_OPTIONAL(enable_l2_tlb_flush)

KVM_X86_OP_OPTIONAL(migrate_timers)

arch/x86/include/asm/kvm_host.h

+2 −2
Original line number Diff line number Diff line
@@ -1745,7 +1745,7 @@ struct kvm_x86_ops { 


	int (*get_msr_feature)(struct kvm_msr_entry *entry);



	bool (*can_emulate_instruction)(struct kvm_vcpu *vcpu, int emul_type,

	int (*check_emulate_instruction)(struct kvm_vcpu *vcpu, int emul_type,

					 void *insn, int insn_len);



	bool (*apic_init_signal_blocked)(struct kvm_vcpu *vcpu);

arch/x86/kvm/svm/svm.c

+21 −29
Original line number Diff line number Diff line
@@ -364,8 +364,6 @@ static void svm_set_interrupt_shadow(struct kvm_vcpu *vcpu, int mask) 
		svm->vmcb->control.int_state |= SVM_INTERRUPT_SHADOW_MASK;



}

static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,

					void *insn, int insn_len);



static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu,

					   bool commit_side_effects)
@@ -386,14 +384,6 @@ static int __svm_skip_emulated_instruction(struct kvm_vcpu *vcpu, 
	}



	if (!svm->next_rip) {

		/*

		 * FIXME: Drop this when kvm_emulate_instruction() does the

		 * right thing and treats "can't emulate" as outright failure

		 * for EMULTYPE_SKIP.

		 */

		if (!svm_can_emulate_instruction(vcpu, EMULTYPE_SKIP, NULL, 0))

			return 0;



		if (unlikely(!commit_side_effects))

			old_rflags = svm->vmcb->save.rflags;
@@ -2202,12 +2192,6 @@ static int shutdown_interception(struct kvm_vcpu *vcpu) 
	struct kvm_run *kvm_run = vcpu->run;

	struct vcpu_svm *svm = to_svm(vcpu);



	/*

	 * The VM save area has already been encrypted so it

	 * cannot be reinitialized - just terminate.

	 */

	if (sev_es_guest(vcpu->kvm))

		return -EINVAL;



	/*

	 * VMCB is undefined after a SHUTDOWN intercept.  INIT the vCPU to put
@@ -2216,9 +2200,14 @@ static int shutdown_interception(struct kvm_vcpu *vcpu) 
	 * userspace.  At a platform view, INIT is acceptable behavior as

	 * there exist bare metal platforms that automatically INIT the CPU

	 * in response to shutdown.

	 *

	 * The VM save area for SEV-ES guests has already been encrypted so it

	 * cannot be reinitialized, i.e. synthesizing INIT is futile.

	 */

	if (!sev_es_guest(vcpu->kvm)) {

		clear_page(svm->vmcb);

		kvm_vcpu_reset(vcpu, true);

	}



	kvm_run->exit_reason = KVM_EXIT_SHUTDOWN;

	return 0;
@@ -4727,7 +4716,7 @@ static void svm_enable_smi_window(struct kvm_vcpu *vcpu) 
}

#endif



static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,

static int svm_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,

					 void *insn, int insn_len)

{

	bool smep, smap, is_user;
@@ -4735,7 +4724,7 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 


	/* Emulation is always possible when KVM has access to all guest state. */

	if (!sev_guest(vcpu->kvm))

		return true;

		return X86EMUL_CONTINUE;



	/* #UD and #GP should never be intercepted for SEV guests. */

	WARN_ON_ONCE(emul_type & (EMULTYPE_TRAP_UD |
@@ -4747,14 +4736,14 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 
	 * to guest register state.

	 */

	if (sev_es_guest(vcpu->kvm))

		return false;

		return X86EMUL_RETRY_INSTR;



	/*

	 * Emulation is possible if the instruction is already decoded, e.g.

	 * when completing I/O after returning from userspace.

	 */

	if (emul_type & EMULTYPE_NO_DECODE)

		return true;

		return X86EMUL_CONTINUE;



	/*

	 * Emulation is possible for SEV guests if and only if a prefilled
@@ -4780,9 +4769,11 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 
	 * success (and in practice it will work the vast majority of the time).

	 */

	if (unlikely(!insn)) {

		if (!(emul_type & EMULTYPE_SKIP))

		if (emul_type & EMULTYPE_SKIP)

			return X86EMUL_UNHANDLEABLE;



		kvm_queue_exception(vcpu, UD_VECTOR);

		return false;

		return X86EMUL_PROPAGATE_FAULT;

	}



	/*
@@ -4793,7 +4784,7 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 
	 * table used to translate CS:RIP resides in emulated MMIO.

	 */

	if (likely(insn_len))

		return true;

		return X86EMUL_CONTINUE;



	/*

	 * Detect and workaround Errata 1096 Fam_17h_00_0Fh.
@@ -4851,6 +4842,7 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 
			kvm_inject_gp(vcpu, 0);

		else

			kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu);

		return X86EMUL_PROPAGATE_FAULT;

	}



resume_guest:
@@ -4868,7 +4860,7 @@ static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 
	 * doesn't explicitly define "ignored", i.e. doing nothing and letting

	 * the guest spin is technically "ignoring" the access.

	 */

	return false;

	return X86EMUL_RETRY_INSTR;

}



static bool svm_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
@@ -5028,7 +5020,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { 
	.vm_copy_enc_context_from = sev_vm_copy_enc_context_from,

	.vm_move_enc_context_from = sev_vm_move_enc_context_from,



	.can_emulate_instruction = svm_can_emulate_instruction,

	.check_emulate_instruction = svm_check_emulate_instruction,



	.apic_init_signal_blocked = svm_apic_init_signal_blocked,

arch/x86/kvm/vmx/vmx.c

+6 −6
Original line number Diff line number Diff line
@@ -1657,7 +1657,7 @@ static int vmx_rtit_ctl_check(struct kvm_vcpu *vcpu, u64 data) 
	return 0;

}



static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,

static int vmx_check_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,

					 void *insn, int insn_len)

{

	/*
@@ -1669,9 +1669,9 @@ static bool vmx_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type, 
	 */

	if (to_vmx(vcpu)->exit_reason.enclave_mode) {

		kvm_queue_exception(vcpu, UD_VECTOR);

		return false;

		return X86EMUL_PROPAGATE_FAULT;

	}

	return true;

	return X86EMUL_CONTINUE;

}



static int skip_emulated_instruction(struct kvm_vcpu *vcpu)
@@ -5792,7 +5792,7 @@ static int handle_ept_misconfig(struct kvm_vcpu *vcpu) 
{

	gpa_t gpa;



	if (!vmx_can_emulate_instruction(vcpu, EMULTYPE_PF, NULL, 0))

	if (vmx_check_emulate_instruction(vcpu, EMULTYPE_PF, NULL, 0))

		return 1;



	/*
@@ -8338,7 +8338,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { 
	.enable_smi_window = vmx_enable_smi_window,

#endif



	.can_emulate_instruction = vmx_can_emulate_instruction,

	.check_emulate_instruction = vmx_check_emulate_instruction,

	.apic_init_signal_blocked = vmx_apic_init_signal_blocked,

	.migrate_timers = vmx_migrate_timers,

arch/x86/kvm/x86.c

+15 −7
Original line number Diff line number Diff line
@@ -7596,10 +7596,10 @@ int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, gva_t addr, void *val, 
}

EXPORT_SYMBOL_GPL(kvm_write_guest_virt_system);



static int kvm_can_emulate_insn(struct kvm_vcpu *vcpu, int emul_type,

static int kvm_check_emulate_insn(struct kvm_vcpu *vcpu, int emul_type,

				  void *insn, int insn_len)

{

	return static_call(kvm_x86_can_emulate_instruction)(vcpu, emul_type,

	return static_call(kvm_x86_check_emulate_instruction)(vcpu, emul_type,

							      insn, insn_len);

}
@@ -7610,8 +7610,10 @@ int handle_ud(struct kvm_vcpu *vcpu) 
	int emul_type = EMULTYPE_TRAP_UD;

	char sig[5]; /* ud2; .ascii "kvm" */

	struct x86_exception e;

	int r;



	if (unlikely(!kvm_can_emulate_insn(vcpu, emul_type, NULL, 0)))

	r = kvm_check_emulate_insn(vcpu, emul_type, NULL, 0);

	if (r != X86EMUL_CONTINUE)

		return 1;



	if (fep_flags &&
@@ -8993,9 +8995,15 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, 
	struct x86_emulate_ctxt *ctxt = vcpu->arch.emulate_ctxt;

	bool writeback = true;



	if (unlikely(!kvm_can_emulate_insn(vcpu, emulation_type, insn, insn_len)))

	r = kvm_check_emulate_insn(vcpu, emulation_type, insn, insn_len);

	if (r != X86EMUL_CONTINUE) {

		if (r == X86EMUL_RETRY_INSTR || r == X86EMUL_PROPAGATE_FAULT)

			return 1;



		WARN_ON_ONCE(r != X86EMUL_UNHANDLEABLE);

		return handle_emulation_failure(vcpu, emulation_type);

	}



	vcpu->arch.l1tf_flush_l1d = true;



	if (!(emulation_type & EMULTYPE_NO_DECODE)) {