linux-kernel - Re: [PATCHv4 01/30] x86/mm: Fix warning on build with X86_MEM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20220228162056.gul22bjr4w6zjslq@black.fi.intel.com>
Date:   Mon, 28 Feb 2022 19:20:56 +0300
From:   "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
To:     Josh Poimboeuf <jpoimboe@...hat.com>
Cc:     tglx@...utronix.de, mingo@...hat.com, bp@...en8.de,
        dave.hansen@...el.com, luto@...nel.org, peterz@...radead.org,
        sathyanarayanan.kuppuswamy@...ux.intel.com, aarcange@...hat.com,
        ak@...ux.intel.com, dan.j.williams@...el.com, david@...hat.com,
        hpa@...or.com, jgross@...e.com, jmattson@...gle.com,
        joro@...tes.org, knsathya@...nel.org, pbonzini@...hat.com,
        sdeep@...are.com, seanjc@...gle.com, tony.luck@...el.com,
        vkuznets@...hat.com, wanpengli@...cent.com,
        thomas.lendacky@....com, brijesh.singh@....com, x86@...nel.org,
        linux-kernel@...r.kernel.org, David Rientjes <rientjes@...gle.com>
Subject: Re: [PATCHv4 01/30] x86/mm: Fix warning on build with
 X86_MEM_ENCRYPT=y

On Sun, Feb 27, 2022 at 02:01:30PM -0800, Josh Poimboeuf wrote:
> On Thu, Feb 24, 2022 at 06:56:01PM +0300, Kirill A. Shutemov wrote:
> > So far, AMD_MEM_ENCRYPT is the only user of X86_MEM_ENCRYPT. TDX will be
> > the second. It will make mem_encrypt.c build without AMD_MEM_ENCRYPT,
> > which triggers a warning:
> > 
> > arch/x86/mm/mem_encrypt.c:69:13: warning: no previous prototype for
> > 	function 'mem_encrypt_init' [-Wmissing-prototypes]
> > 
> > Fix it by moving mem_encrypt_init() declaration outside of #ifdef
> > CONFIG_AMD_MEM_ENCRYPT.
> > 
> > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>
> > Fixes: 20f07a044a76 ("x86/sev: Move common memory encryption code to mem_encrypt.c")
> > Acked-by: David Rientjes <rientjes@...gle.com>
> 
> The patch title, warning, and "Fixes" tag tend to give the impression
> this is fixing a real user-visible bug.  But the bug is theoretical, as
> it's not possible to enable X86_MEM_ENCRYPT without AMD_MEM_ENCRYPT,
> until patch 27.
> 
> IMO it would be preferable to just squash this change with patch 27.
> 
> Having it as a separate patch is also fine, but it shouldn't be
> described as a fix or use the Fixes tag.  It's more of a preparatory
> patch.

maintainer-tip.rst seems disagree with you:

   A Fixes tag should be added even for changes which do not need to be
   backported to stable kernels, i.e. when addressing a recently introduced
   issue which only affects tip or the current head of mainline.

I will leave it as is.

-- 
 Kirill A. Shutemov