================================================================== BUG: KCSAN: data-race in ext4_mb_good_group / mb_mark_used write to 0xffff8881013e3b54 of 4 bytes by task 1820 on cpu 1: mb_mark_used+0x13b/0xc50 fs/ext4/mballoc.c:1947 ext4_mb_use_best_found+0x102/0x300 fs/ext4/mballoc.c:2019 ext4_mb_complex_scan_group+0x57d/0x880 fs/ext4/mballoc.c:2365 ext4_mb_regular_allocator+0x19c8/0x24a0 fs/ext4/mballoc.c:2778 ext4_mb_new_blocks+0x78c/0x1ee0 fs/ext4/mballoc.c:5586 ext4_ext_map_blocks+0x1658/0x2120 fs/ext4/extents.c:4285 ext4_map_blocks+0x71e/0xf00 fs/ext4/inode.c:637 ext4_getblk+0xc6/0x3e0 fs/ext4/inode.c:847 ext4_bread+0x28/0x100 fs/ext4/inode.c:900 ext4_append+0xd1/0x1c0 fs/ext4/namei.c:67 ext4_init_new_dir+0x177/0x500 fs/ext4/namei.c:2893 ext4_mkdir+0x329/0x760 fs/ext4/namei.c:2939 vfs_mkdir+0x2c8/0x3d0 fs/namei.c:3883 do_mkdirat+0x12e/0x2c0 fs/namei.c:3909 __do_sys_mkdir fs/namei.c:3929 [inline] __se_sys_mkdir fs/namei.c:3927 [inline] __x64_sys_mkdir+0x40/0x50 fs/namei.c:3927 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881013e3b54 of 4 bytes by task 1858 on cpu 0: ext4_mb_good_group+0x136/0x370 fs/ext4/mballoc.c:2432 ext4_mb_good_group_nolock fs/ext4/mballoc.c:2545 [inline] ext4_mb_regular_allocator+0x15c2/0x24a0 fs/ext4/mballoc.c:2747 ext4_mb_new_blocks+0x78c/0x1ee0 fs/ext4/mballoc.c:5586 ext4_ext_map_blocks+0x1658/0x2120 fs/ext4/extents.c:4285 ext4_map_blocks+0x71e/0xf00 fs/ext4/inode.c:637 ext4_getblk+0xc6/0x3e0 fs/ext4/inode.c:847 ext4_bread+0x28/0x100 fs/ext4/inode.c:900 ext4_append+0xd1/0x1c0 fs/ext4/namei.c:67 ext4_init_new_dir+0x177/0x500 fs/ext4/namei.c:2893 ext4_mkdir+0x329/0x760 fs/ext4/namei.c:2939 vfs_mkdir+0x2c8/0x3d0 fs/namei.c:3883 do_mkdirat+0x12e/0x2c0 fs/namei.c:3909 __do_sys_mkdir fs/namei.c:3929 [inline] __se_sys_mkdir fs/namei.c:3927 [inline] __x64_sys_mkdir+0x40/0x50 fs/namei.c:3927 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x000007a0 -> 0x0000079f Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 1858 Comm: syz-executor.2 Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================