Building the Linux kernel with Clang and LLVM
 help / color / mirror / Atom feed
From: kernel test robot <lkp@intel.com>
To: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev
Subject: [jpoimboe:sframe-2.1 5/5] kernel/unwind/user.c:179:19: warning: shift count >= width of type
Date: Tue, 17 Sep 2024 21:10:46 +0800	[thread overview]
Message-ID: <202409172133.Uqcuvsht-lkp@intel.com> (raw)

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux.git sframe-2.1
head:   5b35eb7c617539f21cbe3764b0ee0c77567b0f22
commit: 5b35eb7c617539f21cbe3764b0ee0c77567b0f22 [5/5] unwind: Add deferred interfaces
config: i386-defconfig (https://download.01.org/0day-ci/archive/20240917/202409172133.Uqcuvsht-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240917/202409172133.Uqcuvsht-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202409172133.Uqcuvsht-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> kernel/unwind/user.c:179:19: warning: shift count >= width of type [-Wshift-count-overflow]
     179 |                 cookie &= ((1UL << 48) - 1);
         |                                 ^  ~~
   1 warning generated.


vim +179 kernel/unwind/user.c

   165	
   166	{
   167		BUILD_BUG_ON(NR_CPUS > 65535);
   168	
   169		if (WARN_ON_ONCE(in_nmi()))
   170			return -EINVAL;
   171	
   172		local_irq_disable();
   173	
   174		if (!current->unwind_ctx_cookie) {
   175			u64 cpu = smp_processor_id();
   176			u64 cookie;
   177	
   178			cookie = __this_cpu_read(ctx_ctr);
 > 179			cookie &= ((1UL << 48) - 1);
   180			cookie |= ((cpu << 48) + 1);
   181			__this_cpu_write(ctx_ctr, cookie);
   182	
   183			current->unwind_ctx_cookie = cookie;
   184			task_work_add(current, &current->unwind_work, TWA_RESUME);
   185		}
   186	
   187		*ctx_cookie = current->unwind_ctx_cookie;
   188		current->unwind_pending |= (1 << callback->unwind_priv.idx);
   189	
   190		local_irq_enable();
   191	
   192		return 0;
   193	}
   194	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

                 reply	other threads:[~2024-09-17 13:11 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=202409172133.Uqcuvsht-lkp@intel.com \
    --to=lkp@intel.com \
    --cc=jpoimboe@kernel.org \
    --cc=llvm@lists.linux.dev \
    --cc=oe-kbuild-all@lists.linux.dev \
    /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