Re: [tip: x86/urgent] x86/sgx: Set active memcg prior to shmem allocation

From: Borislav Petkov <bp@alien8.de>
To: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: linux-tip-commits@vger.kernel.org,
	Kristen Carlson Accardi <kristen@linux.intel.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Shakeel Butt <shakeelb@google.com>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [tip: x86/urgent] x86/sgx: Set active memcg prior to shmem allocation
Date: Mon, 18 Jul 2022 11:50:33 +0200	[thread overview]
Message-ID: <YtUs3MKLzFg+rqEV@zn.tnic> (raw)
In-Reply-To: <165419442842.4207.2566961916839377924.tip-bot2@tip-bot2>

Just what I think looks like a discrepancy I noticed while merging
tip/master:

On Thu, Jun 02, 2022 at 06:27:08PM -0000, tip-bot2 for Kristen Carlson Accardi wrote:
> diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
> index d44e737..332ef35 100644
> --- a/arch/x86/kernel/cpu/sgx/encl.h
> +++ b/arch/x86/kernel/cpu/sgx/encl.h
> @@ -103,10 +103,13 @@ static inline int sgx_encl_find(struct mm_struct *mm, unsigned long addr,
>  int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
>  		     unsigned long end, unsigned long vm_flags);
>  
> +bool current_is_ksgxd(void);
>  void sgx_encl_release(struct kref *ref);
>  int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm);
> -int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
> -			 struct sgx_backing *backing);
> +int sgx_encl_lookup_backing(struct sgx_encl *encl, unsigned long page_index,
> +			    struct sgx_backing *backing);
> +int sgx_encl_alloc_backing(struct sgx_encl *encl, unsigned long page_index,
> +			   struct sgx_backing *backing);
>  void sgx_encl_put_backing(struct sgx_backing *backing);

So this is making the sgx_encl_get_backing() thing static but its
counterpart sgx_encl_put_backing() is not and is still called by other
places.

Perhaps something wrong with the layering or is this on purpose?

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette