Re: kernel/vmcore_info.c:117 paddr_vmcoreinfo_note() warn: unsigned '_x' is never less than zero.

From: Baoquan He
Date: Sat Feb 15 2025 - 05:25:13 EST


On 02/14/25 at 06:44pm, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 128c8f96eb8638c060cd3532dc394d046ce64fe1
> commit: 443cbaf9e2fdbef7d7cae457434a6cb8a679441b crash: split vmcoreinfo exporting code out from crash_core.c
> date: 12 months ago
> config: riscv-randconfig-r073-20250213 (https://download.01.org/0day-ci/archive/20250214/202502141843.5QoKdQ7g-lkp@xxxxxxxxx/config)
> compiler: riscv32-linux-gcc (GCC) 14.2.0
>
> 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@xxxxxxxxx>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202502141843.5QoKdQ7g-lkp@xxxxxxxxx/
>
> smatch warnings:
> kernel/vmcore_info.c:117 paddr_vmcoreinfo_note() warn: unsigned '_x' is never less than zero.

Thanks for reporting this.

I am preparing to reproduce this issue, while I may not know what are
the steps to reproduce. Just run smatch or just build with the provided
riscv-randconfig-r073-20250213?

>
> vim +/_x +117 kernel/vmcore_info.c
>
> 114
> 115 phys_addr_t __weak paddr_vmcoreinfo_note(void)
> 116 {
> > 117 return __pa(vmcoreinfo_note);
> 118 }
> 119 EXPORT_SYMBOL(paddr_vmcoreinfo_note);
> 120
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
>