KVM: arm/arm64: Fixup the kvm_exit tracepoint

The kvm_exit tracepoint strangely always reported exits as being IRQs.
This seems to be because either the __print_symbolic or the tracepoint
macros use a variable named idx.

Take this chance to update the fields in the tracepoint to reflect the
concepts in the arm64 architecture that we pass to the tracepoint and
move the exception type table to the same location and header files as
the exits code.

We also clear out the exception code to 0 for IRQ exits (which
translates to UNKNOWN in text) to make it slighyly less confusing to
parse the trace output.

Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

arch/arm64/include/asm/kvm_arm.h

@@ -320,10 +320,6 @@
 #define PAR_TO_HPFAR(par)		\
 	(((par) & GENMASK_ULL(PHYS_MASK_SHIFT - 1, 12)) >> 8)
 
-#define kvm_arm_exception_type	\
-	{0, "IRQ" }, 		\
-	{1, "TRAP" }
-
 #define ECN(x) { ESR_ELx_EC_##x, #x }
 
 #define kvm_arm_exception_class \

arch/arm64/include/asm/kvm_asm.h

@@ -34,6 +34,12 @@
 /* The hyp-stub will return this for any kvm_call_hyp() call */
 #define ARM_EXCEPTION_HYP_GONE	  HVC_STUB_ERR
 
+#define kvm_arm_exception_type					\
+	{ARM_EXCEPTION_IRQ,		"IRQ"		},	\
+	{ARM_EXCEPTION_EL1_SERROR, 	"SERROR"	},	\
+	{ARM_EXCEPTION_TRAP, 		"TRAP"		},	\
+	{ARM_EXCEPTION_HYP_GONE,	"HYP_GONE"	}
+
 #ifndef __ASSEMBLY__
 
 #include <linux/mm.h>

virt/kvm/arm/trace.h

@@ -26,25 +26,25 @@ TRACE_EVENT(kvm_entry,
 );
 
 TRACE_EVENT(kvm_exit,
-	TP_PROTO(int idx, unsigned int exit_reason, unsigned long vcpu_pc),
-	TP_ARGS(idx, exit_reason, vcpu_pc),
+	TP_PROTO(int ret, unsigned int esr_ec, unsigned long vcpu_pc),
+	TP_ARGS(ret, esr_ec, vcpu_pc),
 
 	TP_STRUCT__entry(
-		__field(	int,		idx		)
-		__field(	unsigned int,	exit_reason	)
+		__field(	int,		ret		)
+		__field(	unsigned int,	esr_ec		)
 		__field(	unsigned long,	vcpu_pc		)
 	),
 
 	TP_fast_assign(
-		__entry->idx			= idx;
-		__entry->exit_reason		= exit_reason;
+		__entry->ret			= ARM_EXCEPTION_CODE(ret);
+		__entry->esr_ec = (ARM_EXCEPTION_CODE(ret) == ARM_EXCEPTION_TRAP) ? esr_ec : 0;
 		__entry->vcpu_pc		= vcpu_pc;
 	),
 
 	TP_printk("%s: HSR_EC: 0x%04x (%s), PC: 0x%08lx",
-		  __print_symbolic(__entry->idx, kvm_arm_exception_type),
-		  __entry->exit_reason,
-		  __print_symbolic(__entry->exit_reason, kvm_arm_exception_class),
+		  __print_symbolic(__entry->ret, kvm_arm_exception_type),
+		  __entry->esr_ec,
+		  __print_symbolic(__entry->esr_ec, kvm_arm_exception_class),
 		  __entry->vcpu_pc)
 );