Re: [PATCH 1/2] sched: Defend cfs and rt bandwidth quota against overflow

[kbuild test robot]

Hi Huaixin,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on tip/sched/core]
[also build test ERROR on tip/auto-latest linus/master v5.7-rc2 next-20200423]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Huaixin-Chang/Two-small-fixes-for-bandwidth-controller/20200421-230027
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 8f3d9f354286745c751374f5f1fcafee6b3f3136
config: i386-randconfig-a001-20200424 (attached as .config)
compiler: gcc-4.9 (Ubuntu 4.9.3-13ubuntu2) 4.9.3
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@xxxxxxxxx>

All error/warnings (new ones prefixed by >>):

>> kernel/sched/core.c:7394:1: warning: left shift count >= width of type
    static const u64 max_cfs_runtime = MAX_BW_USEC * NSEC_PER_USEC;
    ^
>> kernel/sched/core.c:7394:1: error: initializer element is not computable at load time

vim +7394 kernel/sched/core.c

  7390	
  7391	const u64 max_cfs_quota_period = 1 * NSEC_PER_SEC; /* 1s */
  7392	static const u64 min_cfs_quota_period = 1 * NSEC_PER_MSEC; /* 1ms */
  7393	/* More than 203 days if BW_SHIFT equals 20. */
> 7394	static const u64 max_cfs_runtime = MAX_BW_USEC * NSEC_PER_USEC;
  7395	

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0-DAY CI Kernel Test Service, Intel Corporation
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