linux-kernel - Re: [PATCH V1 2/4] sched: Do predict load

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] [day] [month] [year] [list]

Message-ID: <202502281647.5vhdZuZE-lkp@intel.com>
Date: Fri, 28 Feb 2025 16:38:13 +0800
From: kernel test robot <lkp@...el.com>
To: zihan zhou <15645113830zzh@...il.com>
Cc: llvm@...ts.linux.dev, oe-kbuild-all@...ts.linux.dev, bsegall@...gle.com,
	dietmar.eggemann@....com, juri.lelli@...hat.com,
	linux-kernel@...r.kernel.org, mgorman@...e.de, mingo@...hat.com,
	peterz@...radead.org, rostedt@...dmis.org,
	vincent.guittot@...aro.org, vschneid@...hat.com
Subject: Re: [PATCH V1 2/4] sched: Do predict load

Hi zihan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on tip/sched/core]
[also build test WARNING on akpm-mm/mm-nonmm-unstable brauner-vfs/vfs.all peterz-queue/sched/core linus/master v6.14-rc4 next-20250227]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/zihan-zhou/sched-Add-kconfig-of-predict-load/20250221-165850
base:   tip/sched/core
patch link:    https://lore.kernel.org/r/20250221085051.32468-1-15645113830zzh%40gmail.com
patch subject: [PATCH V1 2/4] sched: Do predict load
config: hexagon-allyesconfig (https://download.01.org/0day-ci/archive/20250228/202502281647.5vhdZuZE-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/20250228/202502281647.5vhdZuZE-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@...el.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202502281647.5vhdZuZE-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> kernel/sched/fair.c:4755:17: warning: variable 'load' is uninitialized when used here [-Wuninitialized]
    4755 |         load = div_u64(load * weight, PREDICT_LOAD_MAX);
         |                        ^~~~
   kernel/sched/fair.c:4749:20: note: initialize the variable 'load' to silence this warning
    4749 |         unsigned long load;
         |                           ^
         |                            = 0
   1 warning generated.


vim +/load +4755 kernel/sched/fair.c

  4746	
  4747	static unsigned long restore_normalized_load(unsigned long normalized_load, unsigned long weight)
  4748	{
  4749		unsigned long load;
  4750	
  4751		//Prevent arithmetic overflow
  4752		WARN_ON_ONCE(normalized_load > 4000000);
  4753		if (weight == PREDICT_LOAD_MAX)
  4754			return normalized_load;
> 4755		load = div_u64(load * weight, PREDICT_LOAD_MAX);
  4756		return load;
  4757	}
  4758	

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