Re: arch/x86/include/asm/preempt.h:79:9: sparse: sparse: context imbalance in 'xfs_iflush_abort' - wrong count at exit

From: Darrick J. Wong
Date: Fri Jul 17 2020 - 16:39:18 EST


On Mon, Jul 13, 2020 at 11:03:53AM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 11ba468877bb23f28956a35e896356252d63c983
> commit: 4165994ac9672d91134675caa6de3645a9ace6c8 xfs: factor common AIL item deletion code
> date: 4 months ago
> config: i386-randconfig-s001-20200713 (attached as .config)
> compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
> reproduce:
> # apt-get install sparse
> # sparse version: v0.6.2-37-gc9676a3b-dirty
> git checkout 4165994ac9672d91134675caa6de3645a9ace6c8
> # save the attached .config to linux build tree
> make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
>
> sparse warnings: (new ones prefixed by >>)
>
> >> arch/x86/include/asm/preempt.h:79:9: sparse: sparse: context imbalance in 'xfs_iflush_abort' - wrong count at exit

Um, does this still need attention?

--D

> vim +/xfs_iflush_abort +79 arch/x86/include/asm/preempt.h
>
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 72
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 73 /*
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 74 * The various preempt_count add/sub methods
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 75 */
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 76
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 77 static __always_inline void __preempt_count_add(int val)
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 78 {
> b3ca1c10d7b32f Christoph Lameter 2014-04-07 @79 raw_cpu_add_4(__preempt_count, val);
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 80 }
> c2daa3bed53a81 Peter Zijlstra 2013-08-14 81
>
> :::::: The code at line 79 was first introduced by commit
> :::::: b3ca1c10d7b32fdfdfaf5484eda486323f52d9be percpu: add raw_cpu_ops
>
> :::::: TO: Christoph Lameter <cl@xxxxxxxxx>
> :::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx