linux-kernel - Re: [PATCH 4/4] x86/percpu: Use C for percpu read/write accessors

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: <EEA95C45-87E6-4033-AEB2-0EC109220074@vmware.com>
Date:   Mon, 9 Oct 2023 12:21:34 +0000
From:   Nadav Amit <namit@...are.com>
To:     Uros Bizjak <ubizjak@...il.com>, Ingo Molnar <mingo@...nel.org>
CC:     Linus Torvalds <torvalds@...ux-foundation.org>,
        the arch/x86 maintainers <x86@...nel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Andy Lutomirski <luto@...nel.org>,
        Brian Gerst <brgerst@...il.com>,
        Denys Vlasenko <dvlasenk@...hat.com>,
        "H . Peter Anvin" <hpa@...or.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Borislav Petkov <bp@...en8.de>,
        Josh Poimboeuf <jpoimboe@...hat.com>
Subject: Re: [PATCH 4/4] x86/percpu: Use C for percpu read/write accessors



> On Oct 9, 2023, at 3:00 PM, Uros Bizjak <ubizjak@...il.com> wrote:
> 
> !! External Email
> 
> On Mon, Oct 9, 2023 at 1:51 PM Ingo Molnar <mingo@...nel.org> wrote:
>> 
>> BTW., while this OK for testing, this is too heavy handed for release
>> purposes, so please only disable the KASAN instrumentation for the affected
>> percpu accessors.
>> 
>> See the various __no_sanitize* attributes available.
> 
> These attributes are for function declarations. The percpu casts can
> not be implemented with separate static inline functions. Also,
> __no_sanitize_address is mutually exclusive with __always_inline.

Right, but for GCC you may be able to do something like:
  
    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-fsanitize=address"
  
    // Your code here...
    #pragma GCC diagnostic pop

Not sure if there is something equivalent in CLANG, and it should be done with
the kernel’s _Pragma.