KVM: PPC: Emulate trap SRR1 flags properly

Book3S needs some flags in SRR1 to get to know details about an interrupt.

One such example is the trap instruction. It tells the guest kernel that
a program interrupt is due to a trap using a bit in SRR1.

This patch implements above behavior, making WARN_ON behave like WARN_ON.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/powerpc/include/asm/kvm_book3s.h

@@ -91,6 +91,7 @@ struct kvmppc_vcpu_book3s {
 	u64 vsid_next;
 	u64 vsid_max;
 	int context_id;
+	ulong prog_flags; /* flags to inject when giving a 700 trap */
 };
 
 #define CONTEXT_HOST		0

arch/powerpc/include/asm/kvm_ppc.h

@@ -80,7 +80,7 @@ extern void kvmppc_core_vcpu_put(struct kvm_vcpu *vcpu);
 
 extern void kvmppc_core_deliver_interrupts(struct kvm_vcpu *vcpu);
 extern int kvmppc_core_pending_dec(struct kvm_vcpu *vcpu);
-extern void kvmppc_core_queue_program(struct kvm_vcpu *vcpu);
+extern void kvmppc_core_queue_program(struct kvm_vcpu *vcpu, ulong flags);
 extern void kvmppc_core_queue_dec(struct kvm_vcpu *vcpu);
 extern void kvmppc_core_dequeue_dec(struct kvm_vcpu *vcpu);
 extern void kvmppc_core_queue_external(struct kvm_vcpu *vcpu,

arch/powerpc/include/asm/reg.h

@@ -426,6 +426,10 @@
 #define   SRR1_WAKEMT		0x00280000 /* mtctrl */
 #define   SRR1_WAKEDEC		0x00180000 /* Decrementer interrupt */
 #define   SRR1_WAKETHERM	0x00100000 /* Thermal management interrupt */
+#define   SRR1_PROGFPE		0x00100000 /* Floating Point Enabled */
+#define   SRR1_PROGPRIV		0x00040000 /* Privileged instruction */
+#define   SRR1_PROGTRAP		0x00020000 /* Trap */
+#define   SRR1_PROGADDR		0x00010000 /* SRR0 contains subsequent addr */
 #define SPRN_HSRR0	0x13A	/* Save/Restore Register 0 */
 #define SPRN_HSRR1	0x13B	/* Save/Restore Register 1 */
 

arch/powerpc/kvm/book3s.c

@@ -168,8 +168,9 @@ void kvmppc_book3s_queue_irqprio(struct kvm_vcpu *vcpu, unsigned int vec)
 }
 
 
-void kvmppc_core_queue_program(struct kvm_vcpu *vcpu)
+void kvmppc_core_queue_program(struct kvm_vcpu *vcpu, ulong flags)
 {
+	to_book3s(vcpu)->prog_flags = flags;
 	kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_PROGRAM);
 }
 
@@ -198,6 +199,7 @@ int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu, unsigned int priority)
 {
 	int deliver = 1;
 	int vec = 0;
+	ulong flags = 0ULL;
 
 	switch (priority) {
 	case BOOK3S_IRQPRIO_DECREMENTER:
@@ -231,6 +233,7 @@ int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu, unsigned int priority)
 		break;
 	case BOOK3S_IRQPRIO_PROGRAM:
 		vec = BOOK3S_INTERRUPT_PROGRAM;
+		flags = to_book3s(vcpu)->prog_flags;
 		break;
 	case BOOK3S_IRQPRIO_VSX:
 		vec = BOOK3S_INTERRUPT_VSX;
@@ -261,7 +264,7 @@ int kvmppc_book3s_irqprio_deliver(struct kvm_vcpu *vcpu, unsigned int priority)
 #endif
 
 	if (deliver)
-		kvmppc_inject_interrupt(vcpu, vec, 0ULL);
+		kvmppc_inject_interrupt(vcpu, vec, flags);
 
 	return deliver;
 }

arch/powerpc/kvm/booke.c

@@ -82,8 +82,9 @@ static void kvmppc_booke_queue_irqprio(struct kvm_vcpu *vcpu,
 	set_bit(priority, &vcpu->arch.pending_exceptions);
 }
 
-void kvmppc_core_queue_program(struct kvm_vcpu *vcpu)
+void kvmppc_core_queue_program(struct kvm_vcpu *vcpu, ulong flags)
 {
+	/* BookE does flags in ESR, so ignore those we get here */
 	kvmppc_booke_queue_irqprio(vcpu, BOOKE_IRQPRIO_PROGRAM);
 }
 

arch/powerpc/kvm/emulate.c

@@ -154,7 +154,7 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
 #else
 		vcpu->arch.esr |= ESR_PTR;
 #endif
-		kvmppc_core_queue_program(vcpu);
+		kvmppc_core_queue_program(vcpu, SRR1_PROGTRAP);
 		advance = 0;
 		break;