Hi Anand, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on kdave/for-next] [also build test WARNING on v5.16-rc4 next-20211208] [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/Anand-Jain/btrfs-harden-identifi... base: https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next config: i386-randconfig-s001-20211207 (https://download.01.org/0day-ci/archive/20211209/202112091123.ETjD5KQj-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.4-dirty # https://github.com/0day-ci/linux/commit/03b597640967afb3d37dc37f0a685fed9... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Anand-Jain/btrfs-harden-identification-of-the-stale-device/20211208-220757 git checkout 03b597640967afb3d37dc37f0a685fed95594b83 # save the config file to linux build tree mkdir build_dir make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) fs/btrfs/volumes.c:402:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct rcu_string *str @@ got struct rcu_string [noderef] __rcu *name @@ fs/btrfs/volumes.c:402:31: sparse: expected struct rcu_string *str fs/btrfs/volumes.c:402:31: sparse: got struct rcu_string [noderef] __rcu *name fs/btrfs/volumes.c:549:35: sparse: expected char const *pathname fs/btrfs/volumes.c:549:35: sparse: got char [noderef] __rcu * fs/btrfs/volumes.c:643:43: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected char const *device_path @@ got char [noderef] __rcu * @@ fs/btrfs/volumes.c:643:43: sparse: expected char const *device_path fs/btrfs/volumes.c:643:43: sparse: got char [noderef] __rcu * fs/btrfs/volumes.c:904:50: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected char const *cs @@ got char [noderef] __rcu * @@ fs/btrfs/volumes.c:904:50: sparse: expected char const *cs fs/btrfs/volumes.c:904:50: sparse: got char [noderef] __rcu * fs/btrfs/volumes.c:984:39: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct rcu_string *str @@ got struct rcu_string [noderef] __rcu *name @@ fs/btrfs/volumes.c:984:39: sparse: expected struct rcu_string *str fs/btrfs/volumes.c:984:39: sparse: got struct rcu_string [noderef] __rcu *name fs/btrfs/volumes.c:1040:58: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected char const *src @@ got char [noderef] __rcu * @@ fs/btrfs/volumes.c:1040:58: sparse: expected char const *src fs/btrfs/volumes.c:1040:58: sparse: got char [noderef] __rcu * fs/btrfs/volumes.c:2235:49: sparse: sparse: incorrect type in argument 3 (different address spaces) @@ expected char const *device_path @@ got char [noderef] __rcu * @@ fs/btrfs/volumes.c:2235:49: sparse: expected char const *device_path fs/btrfs/volumes.c:2235:49: sparse: got char [noderef] __rcu * fs/btrfs/volumes.c:2350:41: sparse: sparse: incorrect type in argument 3 (different address spaces) @@ expected char const *device_path @@ got char [noderef] __rcu * @@ fs/btrfs/volumes.c:2350:41: sparse: expected char const *device_path fs/btrfs/volumes.c:2350:41: sparse: got char [noderef] __rcu * vim +549 fs/btrfs/volumes.c 532 533 /* 534 * Check if the device in the 'path' matches with the device in the given 535 * struct btrfs_device '*device'. 536 * Returns: 537 * 0 If it is the same device. 538 * 1 If it is not the same device. 539 * -errno For error. 540 */ 541 static int device_matched(struct btrfs_device *device, const char *path) 542 { 543 dev_t dev_old; 544 dev_t dev_new; 545 int error; 546 547 lockdep_assert_held(&device->fs_devices->device_list_mutex); 548 /* rcu is not required as we are inside the device_list_mutex */ 550 if (error) 551 return error; 552 553 error = lookup_bdev(path, &dev_new); 554 if (error) 555 return error; 556 557 if (dev_old == dev_new) 558 return 0; 559 560 return 1; 561 } 562 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org