On Thu, Nov 03, 2022, Isaku Yamahata wrote:

On Wed, Nov 02, 2022 at 11:19:03PM +0000,
Sean Christopherson [off-list ref] wrote:

quoted

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index f223c845ed6e..c99222b71fcc 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h

@@ -1666,7 +1666,7 @@ struct kvm_x86_nested_ops {
 };
 
 struct kvm_x86_init_ops {
-	int (*check_processor_compatibility)(void);
+	int (*check_processor_compatibility)(int cpu);

Is this cpu argument used only for error message to include cpu number
with avoiding repeating raw_smp_processor_id() in pr_err()?

Yep.

The actual check is done on the current executing cpu.

If cpu != raw_smp_processor_id(), cpu is wrong. Although the function is called
in non-preemptive context, it's a bit confusing. So voting to remove it and
to use.

What if I rename the param is this_cpu?  I 100% agree the argument is confusing
as-is, but forcing all the helpers to manually grab the cpu is quite annoying.