Hi Pradeep, Thank you for the patch! Yet something to improve: [auto build test ERROR on fuse/for-next] [also build test ERROR on v5.9-rc1 next-20200820] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Pradeep-P-V-K/fuse-Fix-VM_BUG_ON... base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next config: x86_64-randconfig-a003-20200820 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 4deda57106f7c9b982a49cb907c33e3966c8de7f) 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 # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): if (req->ff) ~~~ ^ fs/fuse/dev.c:956:19: error: no member named 'ff' in 'struct fuse_req' spin_lock(&req->ff->fc->lock); ~~~ ^ fs/fuse/dev.c:968:11: error: no member named 'ff' in 'struct fuse_req' if (req->ff) ~~~ ^ fs/fuse/dev.c:969:21: error: no member named 'ff' in 'struct fuse_req' spin_unlock(&req->ff->fc->lock); ~~~ ^ 4 errors generated. # https://github.com/0day-ci/linux/commit/776d24e60b6fdfbd88fc0cf0bf0485929... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Pradeep-P-V-K/fuse-Fix-VM_BUG_ON_PAGE-issue-while-accessing-zero-ref-count-page/20200821-005756 git checkout 776d24e60b6fdfbd88fc0cf0bf04859293d42bd6 vim +955 fs/fuse/dev.c 945 946 /* Copy pages in the request to/from userspace buffer */ 947 static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes, 948 int zeroing) 949 { 950 unsigned i; 951 int err = 0; 952 struct fuse_req *req = cs->req; 953 struct fuse_args_pages *ap = container_of(req->args, typeof(*ap), args); 954 956 spin_lock(&req->ff->fc->lock); 957 for (i = 0; i < ap->num_pages && (nbytes || zeroing); i++) { 958 unsigned int offset = ap->descs[i].offset; 959 unsigned int count = min(nbytes, ap->descs[i].length); 960 961 err = fuse_copy_page(cs, &ap->pages[i], offset, count, zeroing); 962 if (err) 963 goto err; 964 965 nbytes -= count; 966 } 967 err: 968 if (req->ff) 969 spin_unlock(&req->ff->fc->lock); 970 return err; 971 } 972 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org