Hi, On Sat, Jul 25, 2020 at 03:15:39PM +0800, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > master > head: 23ee3e4e5bd27bdbc0f1785eef7209ce872794c7 > commit: 47e4937a4a7ca4184fd282791dfee76c6799966a erofs: move erofs out of > staging > date: 11 months ago > config: alpha-randconfig-s031-20200725 (attached as .config) > compiler: alpha-linux-gcc (GCC) 9.3.0 > reproduce: > wget > https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O > ~/bin/make.cross > chmod +x ~/bin/make.cross > # apt-get install sparse > # sparse version: v0.6.2-93-g4c6cbe55-dirty > git checkout 47e4937a4a7ca4184fd282791dfee76c6799966a > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 > CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=alpha > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <[email protected]> > > > sparse warnings: (new ones prefixed by >>) > > fs/erofs/zdata.c: note: in included file (through > arch/alpha/include/asm/cmpxchg.h, arch/alpha/include/asm/atomic.h, > include/linux/atomic.h, ...): > >> arch/alpha/include/asm/xchg.h:234:32: sparse: sparse: cast truncates bits > >> from constant value (5f0ecafe becomes fe) > >> arch/alpha/include/asm/xchg.h:236:32: sparse: sparse: cast truncates bits > >> from constant value (5f0ecafe becomes cafe) > >> arch/alpha/include/asm/xchg.h:234:32: sparse: sparse: cast truncates bits > >> from constant value (5f0ecafe becomes fe) > >> arch/alpha/include/asm/xchg.h:234:32: sparse: sparse: cast truncates bits > >> from constant value (5f0edead becomes ad) > >> arch/alpha/include/asm/xchg.h:236:32: sparse: sparse: cast truncates bits > >> from constant value (5f0ecafe becomes cafe) > >> arch/alpha/include/asm/xchg.h:236:32: sparse: sparse: cast truncates bits > >> from constant value (5f0edead becomes dead)
I'm not sure what's wrong here? What should I proceed with it (it seems relating with Alpha architecture? since I didn't notice the sparse warning in x86 and arm) Z_EROFS_PCLUSTER_TAIL is a pointer with magic value to indicate the end of opening decompressing chain, whose function is likewise the function of POISON_POINTER_DELTA and CONFIG_ILLEGAL_POINTER_VALUE. Thanks, Gao Xiang
