linux-kernel - Re: [PATCH v2 04/14] x86: Handle KCOV _

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Message-ID: <202505231327.3FA45E4B@keescook>
Date: Fri, 23 May 2025 13:28:28 -0700
From: Kees Cook <kees@...nel.org>
To: Sean Christopherson <seanjc@...gle.com>
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Subject: Re: [PATCH v2 04/14] x86: Handle KCOV __init vs inline mismatches

On Fri, May 23, 2025 at 07:35:03AM -0700, Sean Christopherson wrote:
> On Thu, May 22, 2025, Kees Cook wrote:
> > diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> > index 921c1c783bc1..72f13d643fca 100644
> > --- a/arch/x86/kernel/kvm.c
> > +++ b/arch/x86/kernel/kvm.c
> > @@ -420,7 +420,7 @@ static u64 kvm_steal_clock(int cpu)
> >  	return steal;
> >  }
> >  
> > -static inline void __set_percpu_decrypted(void *ptr, unsigned long size)
> > +static __always_inline void __set_percpu_decrypted(void *ptr, unsigned long size)
> 
> I'd rather drop the "inline" and explicitly mark this "__init".  There's value
> in documenting and enforcing that memory is marked decrypted/shared only during
> boot.

Sure! I will swap this around. Thanks!

-Kees

-- 
Kees Cook