Re: fs/btrfs/lzo.o: warning: objtool: lzo_compress_folios+0xb0: unreachable instruction

[Philip Li]

On Tue, Jul 23, 2024 at 08:18:41PM +0800, kernel test robot wrote:
> Hi Qu,
> 
> FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.
> 
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head:   66ebbdfdeb093e097399b1883390079cd4c3022b
> commit: 400b172b8cdcff87038697169fe9e4222120dd9a btrfs: compression: migrate compression/decompression paths to folios
> date:   3 months ago
> config: loongarch-randconfig-001-20240722 (https://download.01.org/0day-ci/archive/20240723/202407232006.7Gelsbv4-lkp@xxxxxxxxx/config)
> compiler: loongarch64-linux-gcc (GCC) 14.1.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240723/202407232006.7Gelsbv4-lkp@xxxxxxxxx/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@xxxxxxxxx>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202407232006.7Gelsbv4-lkp@xxxxxxxxx/
> 
> All warnings (new ones prefixed by >>):

Sorry, kindly ignore this report which could be related to tool chain upgrade to
loongarch64-linux-gcc (GCC) 14.1.0.

We will further check whether the issue can be reproduced on gcc-13.

> 
> >> fs/btrfs/lzo.o: warning: objtool: lzo_compress_folios+0xb0: unreachable instruction
>    fs/btrfs/lzo.o: warning: objtool: lzo_decompress_bio+0x140: unreachable instruction
> 
> 
> objdump-func vmlinux.o lzo_compress_folios:
> 
> -- 
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
>