Hi "zhangyi, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [cannot apply to v5.3-rc3 next-20190807] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/zhangyi-F/ext4-fix-potential-use-after-free-in-system-zone-via-remount-with-noblock_validity/20190804-163619 reproduce: # apt-get install sparse # sparse version: v0.6.1-rc1-7-g2b96cd8-dirty make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> sparse warnings: (new ones prefixed by >>) include/linux/sched.h:609:43: sparse: sparse: bad integer constant expression include/linux/sched.h:609:73: sparse: sparse: invalid named zero-width bitfield `value' include/linux/sched.h:610:43: sparse: sparse: bad integer constant expression include/linux/sched.h:610:67: sparse: sparse: invalid named zero-width bitfield `bucket_id' include/linux/rbtree.h:84:9: sparse: sparse: incompatible types in comparison expression (different address spaces): include/linux/rbtree.h:84:9: sparse: struct rb_node [noderef] <asn:4> * include/linux/rbtree.h:84:9: sparse: struct rb_node * >> fs/ext4/block_validity.c:252:9: sparse: sparse: incompatible types in comparison expression (different address spaces): >> fs/ext4/block_validity.c:252:9: sparse: struct rb_node [noderef] <asn:4> * >> fs/ext4/block_validity.c:252:9: sparse: struct rb_node * vim +252 fs/ext4/block_validity.c 246 247 /* Called when the filesystem is unmounted */ 248 void ext4_release_system_zone(struct super_block *sb) 249 { 250 struct ext4_system_zone *entry, *n; 251 > 252 rcu_assign_pointer(EXT4_SB(sb)->system_blks.rb_node, NULL); 253 254 rbtree_postorder_for_each_entry_safe(entry, n, 255 &EXT4_SB(sb)->system_blks, node) 256 call_rcu(&entry->rcu, destroy_system_zone); 257 } 258 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation