On 12/17/22 at 02:41pm, kernel test robot wrote: > Hi Baoquan, > > I love your patch! Perhaps something to improve: > > [auto build test WARNING on akpm-mm/mm-everything] > > url: https://github.com/intel-lab-lkp/linux/commits/Baoquan-He/mm-vmalloc-c-allow-vread-to-read-out-vm_map_ram-areas/20221217-095615 > base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything > patch link: https://lore.kernel.org/r/20221217015435.73889-4-bhe%40redhat.com > patch subject: [PATCH v2 3/7] mm/vmalloc.c: allow vread() to read out vm_map_ram areas > config: loongarch-randconfig-r006-20221216 > compiler: loongarch64-linux-gcc (GCC) 12.1.0 > reproduce (this is a W=1 build): > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # https://github.com/intel-lab-lkp/linux/commit/368cd65be8fedd1642e53393dc3f28ff8726122d > git remote add linux-review https://github.com/intel-lab-lkp/linux > git fetch --no-tags linux-review Baoquan-He/mm-vmalloc-c-allow-vread-to-read-out-vm_map_ram-areas/20221217-095615 > git checkout 368cd65be8fedd1642e53393dc3f28ff8726122d > # save the config file > mkdir build_dir && cp config build_dir/.config > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch olddefconfig > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash > > If you fix the issue, kindly add following tag where applicable > | Reported-by: kernel test robot <lkp@xxxxxxxxx> > > All warnings (new ones prefixed by >>): > > mm/vmalloc.c: In function 'vb_vread': > >> mm/vmalloc.c:3563:49: warning: suggest parentheses around '-' inside '<<' [-Wparentheses] > 3563 | n = (re - rs + 1) << PAGE_SHIFT - offset; Thanks, below code change can fix the warning. diff --git a/mm/vmalloc.c b/mm/vmalloc.c index bdaceda1b878..ec5665e70114 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -3544,7 +3544,7 @@ static void vb_vread(char *buf, char *addr, int count) } /*it could start reading from the middle of used region*/ offset = offset_in_page(addr); - n = (re - rs + 1) << PAGE_SHIFT - offset; + n = ((re - rs + 1) << PAGE_SHIFT) - offset; if (n > count) n = count; aligned_vread(buf, start+offset, n);
