From: Andrey Konovalov <andreyknvl@google.com>
To: Andrew Morton <akpm@linux-foundation.org>,
kernel test robot <lkp@intel.com>
Cc: kbuild-all@lists.01.org,
clang-built-linux <clang-built-linux@googlegroups.com>,
LKML <linux-kernel@vger.kernel.org>,
Linux Memory Management List <linux-mm@kvack.org>,
Arnd Bergmann <arnd@arndb.de>
Subject: Re: drivers/video/backlight/ltv350qv.c:192:12: warning: stack frame size of 13472 bytes in function 'ltv350qv_power'
Date: Thu, 29 Oct 2020 16:28:06 +0100 [thread overview]
Message-ID: <CAAeHK+wdv=X-iD208M2m3Xte9F+g2kYRDqQr4A+GP7Z1tY85BA@mail.gmail.com> (raw)
In-Reply-To: <20201025121708.04d4070a44e28146baf9a6a7@linux-foundation.org>
On Sun, Oct 25, 2020 at 8:17 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Mon, 26 Oct 2020 02:15:37 +0800 kernel test robot <lkp@intel.com> wrote:
>
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > head: d76913908102044f14381df865bb74df17a538cb
> > commit: cae9dc35ed9ff82a99754e51d57ff6c332e1f7e4 kasan: allow enabling stack tagging for tag-based mode
> > date: 3 months ago
> > config: arm64-randconfig-r005-20201026 (attached as .config)
> > compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 1c8371692dfe8245bc6690ff1262dcced4649d21)
> > reproduce (this is a W=1 build):
> > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > chmod +x ~/bin/make.cross
> > # install arm64 cross compiling tool for clang build
> > # apt-get install binutils-aarch64-linux-gnu
> > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cae9dc35ed9ff82a99754e51d57ff6c332e1f7e4
> > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> > git fetch --no-tags linus master
> > git checkout cae9dc35ed9ff82a99754e51d57ff6c332e1f7e4
> > # save the attached .config to linux build tree
> > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
> >
> > If you fix the issue, kindly add following tag as appropriate
> > Reported-by: kernel test robot <lkp@intel.com>
> >
> > All warnings (new ones prefixed by >>):
> >
> > >> drivers/video/backlight/ltv350qv.c:192:12: warning: stack frame size of 13472 bytes in function 'ltv350qv_power' [-Wframe-larger-than=]
>
> That's a lot of stack.
>
> > static int ltv350qv_power(struct ltv350qv *lcd, int power)
> > ^
> > 1 warning generated.
> >
> > vim +/ltv350qv_power +192 drivers/video/backlight/ltv350qv.c
>
> Odd - the code looks pretty normal. It is possible that your compiler
> is (crazily) inlining ltv350qv_write_reg()?
This is the same issue in LLVM that was reported by Arnd for generic
KASAN (also see KASAN_STACK_ENABLE option description). By default
KASAN shouldn't have stack instrumentation enabled unless
KASAN_STACK_ENABLE is specified. Perhaps it makes sense to disable it
for KASAN_SW_TAGS config on the kernel test robot.
[1] https://bugs.llvm.org/show_bug.cgi?id=38809
next prev parent reply other threads:[~2020-10-29 15:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-25 18:15 kernel test robot
2020-10-25 19:17 ` Andrew Morton
2020-10-25 19:23 ` Joe Perches
2020-10-28 15:46 ` Daniel Thompson
2020-10-29 15:28 ` Andrey Konovalov [this message]
2020-10-30 13:28 ` [kbuild-all] " Chen, Rong A
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='CAAeHK+wdv=X-iD208M2m3Xte9F+g2kYRDqQr4A+GP7Z1tY85BA@mail.gmail.com' \
--to=andreyknvl@google.com \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=clang-built-linux@googlegroups.com \
--cc=kbuild-all@lists.01.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=lkp@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
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