arm/arm64: KVM: Use set/way op trapping to track the state of the caches
Trying to emulate the behaviour of set/way cache ops is fairly
pointless, as there are too many ways we can end-up missing stuff.
Also, there is some system caches out there that simply ignore
set/way operations.
So instead of trying to implement them, let's convert it to VA ops,
and use them as a way to re-enable the trapping of VM ops. That way,
we can detect the point when the MMU/caches are turned off, and do
a full VM flush (which is what the guest was trying to do anyway).
This allows a 32bit zImage to boot on the APM thingy, and will
probably help bootloaders in general.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
index b1d640f..b6a6e71 100644
--- a/arch/arm/kvm/trace.h
+++ b/arch/arm/kvm/trace.h
@@ -223,6 +223,45 @@
__entry->vcpu_pc, __entry->r0, __entry->imm)
);
+TRACE_EVENT(kvm_set_way_flush,
+ TP_PROTO(unsigned long vcpu_pc, bool cache),
+ TP_ARGS(vcpu_pc, cache),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ __field( bool, cache )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ __entry->cache = cache;
+ ),
+
+ TP_printk("S/W flush at 0x%016lx (cache %s)",
+ __entry->vcpu_pc, __entry->cache ? "on" : "off")
+);
+
+TRACE_EVENT(kvm_toggle_cache,
+ TP_PROTO(unsigned long vcpu_pc, bool was, bool now),
+ TP_ARGS(vcpu_pc, was, now),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ __field( bool, was )
+ __field( bool, now )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ __entry->was = was;
+ __entry->now = now;
+ ),
+
+ TP_printk("VM op at 0x%016lx (cache was %s, now %s)",
+ __entry->vcpu_pc, __entry->was ? "on" : "off",
+ __entry->now ? "on" : "off")
+);
+
#endif /* _TRACE_KVM_H */
#undef TRACE_INCLUDE_PATH