On Sat, May 6, 2023 at 5:28 PM kernel test robot <lkp@xxxxxxxxx> wrote: > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: 83e5775d7afda68f6d7576d21f7a080fbfeecc4f > commit: d39c65bc7fcb1dad22dc1585fc669b5bfe5d3108 [14680/14811] cachestat: implement cachestat syscall > config: s390-randconfig-s041-20230507 (https://download.01.org/0day-ci/archive/20230507/202305070840.X0G3ofjl-lkp@xxxxxxxxx/config) > compiler: s390-linux-gcc (GCC) 12.1.0 > 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: v0.6.4-39-gce1a6720-dirty > # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=d39c65bc7fcb1dad22dc1585fc669b5bfe5d3108 > git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git > git fetch --no-tags linux-next master > git checkout d39c65bc7fcb1dad22dc1585fc669b5bfe5d3108 > # save the config file > mkdir build_dir && cp config build_dir/.config > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=s390 olddefconfig > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=s390 SHELL=/bin/bash > > If you fix the issue, kindly add following tag where applicable > | Reported-by: kernel test robot <lkp@xxxxxxxxx> > | Link: https://lore.kernel.org/oe-kbuild-all/202305070840.X0G3ofjl-lkp@xxxxxxxxx/ > > sparse warnings: (new ones prefixed by >>) > mm/filemap.c:1416:17: sparse: sparse: context imbalance in 'migration_entry_wait_on_locked' - unexpected unlock > >> mm/filemap.c:4250:1: sparse: sparse: Using plain integer as NULL pointer > >> mm/filemap.c:4250:1: sparse: sparse: Using plain integer as NULL pointer > >> mm/filemap.c:4250:1: sparse: sparse: Using plain integer as NULL pointer > >> mm/filemap.c:4250:1: sparse: sparse: Using plain integer as NULL pointer > > vim +4250 mm/filemap.c > > 4215 > 4216 /* > 4217 * The cachestat(2) system call. > 4218 * > 4219 * cachestat() returns the page cache statistics of a file in the > 4220 * bytes range specified by `off` and `len`: number of cached pages, > 4221 * number of dirty pages, number of pages marked for writeback, > 4222 * number of evicted pages, and number of recently evicted pages. > 4223 * > 4224 * An evicted page is a page that is previously in the page cache > 4225 * but has been evicted since. A page is recently evicted if its last > 4226 * eviction was recent enough that its reentry to the cache would > 4227 * indicate that it is actively being used by the system, and that > 4228 * there is memory pressure on the system. > 4229 * > 4230 * `off` and `len` must be non-negative integers. If `len` > 0, > 4231 * the queried range is [`off`, `off` + `len`]. If `len` == 0, > 4232 * we will query in the range from `off` to the end of the file. > 4233 * > 4234 * The `flags` argument is unused for now, but is included for future > 4235 * extensibility. User should pass 0 (i.e no flag specified). > 4236 * > 4237 * Currently, hugetlbfs is not supported. > 4238 * > 4239 * Because the status of a page can change after cachestat() checks it > 4240 * but before it returns to the application, the returned values may > 4241 * contain stale information. > 4242 * > 4243 * return values: > 4244 * zero - success > 4245 * -EFAULT - cstat or cstat_range points to an illegal address > 4246 * -EINVAL - invalid flags > 4247 * -EBADF - invalid file descriptor > 4248 * -EOPNOTSUPP - file descriptor is of a hugetlbfs file > 4249 */ > > 4250 SYSCALL_DEFINE4(cachestat, unsigned int, fd, > > -- > 0-DAY CI Kernel Test Service > https://github.com/intel/lkp-tests Hmm I couldn't see where I used 0 as the null pointer. Maybe this is a false positive or a result of not wiring up the syscall for s390? Especially since this is pointed toward the macro line (SYSCALL_DEFINE). cc-ing this to s390 maintainers and the s390 mailing list... Could you help me debug this? Thanks!