public inbox for linuxppc-dev@ozlabs.org 
 help / color / mirror / Atom feed
From: Michael Ellerman <mpe@ellerman•id.au>
To: Marco Elver <elver@google•com>,
	Andrew Morton <akpm@linux-foundation•org>
Cc: kernel test robot <lkp@intel•com>, Daniel Axtens <dja@axtens•net>,
	linux-kernel@vger•kernel.org, Nicholas Piggin <npiggin@gmail•com>,
	linux-mm@kvack•org, Andrey Ryabinin <ryabinin.a.a@gmail•com>,
	Alexander Potapenko <glider@google•com>,
	Liam Howlett <liam.howlett@oracle•com>,
	kasan-dev@googlegroups•com,
	Vincenzo Frascino <vincenzo.frascino@arm•com>,
	linuxppc-dev@lists•ozlabs.org, Dmitry Vyukov <dvyukov@google•com>,
	Andrey Konovalov <andreyknvl@gmail•com>
Subject: Re: [PATCH mm] kasan, powerpc: Don't rename memintrinsics if compiler adds prefixes
Date: Tue, 28 Feb 2023 22:58:03 +1100	[thread overview]
Message-ID: <87o7peuhmc.fsf@mpe.ellerman.id.au> (raw)
In-Reply-To: <CANpmjNNtxW41H8ju6iog=ynMdEE0awa7GYabsuL6ZRihmVYQHw@mail.gmail.com>

Marco Elver <elver@google•com> writes:
> On Mon, 27 Feb 2023 at 23:16, Andrew Morton <akpm@linux-foundation•org> wrote:
>>
>> On Mon, 27 Feb 2023 10:47:27 +0100 Marco Elver <elver@google•com> wrote:
>>
>> > With appropriate compiler support [1], KASAN builds use __asan prefixed
>> > meminstrinsics, and KASAN no longer overrides memcpy/memset/memmove.
>> >
>> > If compiler support is detected (CC_HAS_KASAN_MEMINTRINSIC_PREFIX),
>> > define memintrinsics normally (do not prefix '__').
>> >
>> > On powerpc, KASAN is the only user of __mem functions, which are used to
>> > define instrumented memintrinsics. Alias the normal versions for KASAN
>> > to use in its implementation.
>> >
>> > Link: https://lore.kernel.org/all/20230224085942.1791837-1-elver@google.com/ [1]
>> > Link: https://lore.kernel.org/oe-kbuild-all/202302271348.U5lvmo0S-lkp@intel.com/
>> > Reported-by: kernel test robot <lkp@intel•com>
>> > Signed-off-by: Marco Elver <elver@google•com>
>>
>> Seems this is a fix against "kasan: treat meminstrinsic as builtins in
>> uninstrumented files", so I'll plan to fold this patch into that patch.
>
> Yes, that looks right.
>
> If a powerpc maintainer could take a quick look as well would be good.

The patch looks OK to me. It builds for various configs and I did a few
test boots with KASAN enabled, everything seems normal.

Acked-by: Michael Ellerman <mpe@ellerman•id.au> (powerpc)


> The maze of memcpy/memmove/memset definitions and redefinitions isn't
> the simplest - I hope in a few years we can delete all the old code
> (before CC_HAS_KASAN_MEMINTRINSIC_PREFIX), and let the compilers just
> "do the right thing".

Yeah that would be nice.

cheers

      reply	other threads:[~2023-02-28 11:59 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-02-27  9:47 [PATCH mm] kasan, powerpc: Don't rename memintrinsics if compiler adds prefixes Marco Elver
2023-02-27 22:16 ` Andrew Morton
2023-02-27 23:09   ` Marco Elver
2023-02-28 11:58     ` Michael Ellerman [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87o7peuhmc.fsf@mpe.ellerman.id.au \
    --to=mpe@ellerman$(echo .)id.au \
    --cc=akpm@linux-foundation$(echo .)org \
    --cc=andreyknvl@gmail$(echo .)com \
    --cc=dja@axtens$(echo .)net \
    --cc=dvyukov@google$(echo .)com \
    --cc=elver@google$(echo .)com \
    --cc=glider@google$(echo .)com \
    --cc=kasan-dev@googlegroups$(echo .)com \
    --cc=liam.howlett@oracle$(echo .)com \
    --cc=linux-kernel@vger$(echo .)kernel.org \
    --cc=linux-mm@kvack$(echo .)org \
    --cc=linuxppc-dev@lists$(echo .)ozlabs.org \
    --cc=lkp@intel$(echo .)com \
    --cc=npiggin@gmail$(echo .)com \
    --cc=ryabinin.a.a@gmail$(echo .)com \
    --cc=vincenzo.frascino@arm$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox