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

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Message-ID: <aDCHl0RBMgNzGu6j@google.com>
Date: Fri, 23 May 2025 07:35:03 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Kees Cook <kees@...nel.org>
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Subject: Re: [PATCH v2 04/14] x86: Handle KCOV __init vs inline mismatches

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.

>  {
>  	early_set_memory_decrypted((unsigned long) ptr, size);
>  }