Re: [PATCH v7 02/23] KVM: Make device name configurable

[Steffen Eiden <seiden@linux.ibm.com>]

On Tue, Sep 01, 2026 at 05:40:25PM -0700, Sean Christopherson wrote:
> On Mon, Aug 31, 2026, Steffen Eiden wrote:
> > Allow KVM implementations to choose alternative device names. This is
> > especially useful for architectures providing multiple KVM
> > implementations simultaneously. Architectures providing multiple KVM
> > implementations must compile the KVM common code once per
> > implementation and mange symbols.
> 
> What about tracepoints?  Or do those show up as "kvm" and "kvm-arm64"?

Yes, I want them to show up as kvm and  kvm-arm64.

Thanks for pointing that out - I just noticed that I forgot to switch
the trace system to kvm-arm64 for the common tracepoints in
trace/events/kvm.h
I only did it for the arch-local traces in PATCH 21.

I would just do the following:

diff --git a/include/trace/events/kvm.h b/include/trace/events/kvm.h
index b282e3a86769..5d4f8a0693a3 100644
--- a/include/trace/events/kvm.h
+++ b/include/trace/events/kvm.h
@@ -5,7 +5,11 @@
 #include <linux/tracepoint.h>

 #undef TRACE_SYSTEM
+#ifdef KVM_S390_ARM64
+#define TRACE_SYSTEM kvm-arm64
+#else
 #define TRACE_SYSTEM kvm
+#endif /* KVM_S390_ARM64 */

 #define ERSN(x) { KVM_EXIT_##x, "KVM_EXIT_" #x }


This would leak a bit of arm on s390 into common KVM but I do not see
another way.

KVM_S390_ARM64 is defined for all arm-on-s390 compile units.

I think I'll add this in PATCH 14? of this series or create a separate
PATCH.

Does this make sense?

	Steffen