================================================================== BUG: KCSAN: data-race in ext4_mb_regular_allocator / mb_free_blocks read-write to 0xffff888141712014 of 4 bytes by task 17192 on cpu 1: mb_free_blocks+0x13d/0xe00 fs/ext4/mballoc.c:1486 ext4_free_blocks+0x13b2/0x1c80 fs/ext4/mballoc.c:5470 ext4_ext_try_to_merge_up fs/ext4/extents.c:1830 [inline] ext4_ext_try_to_merge+0x2fa/0x310 fs/ext4/extents.c:1857 ext4_swap_extents+0x102d/0x13a0 fs/ext4/extents.c:5693 move_extent_per_page+0x1309/0x1590 fs/ext4/move_extent.c:339 ext4_move_extents+0xab2/0xc00 fs/ext4/move_extent.c:673 __ext4_ioctl fs/ext4/ioctl.c:988 [inline] ext4_ioctl+0x2120/0x3540 fs/ext4/ioctl.c:1319 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff888141712014 of 4 bytes by task 17189 on cpu 0: ext4_mb_good_group_nolock fs/ext4/mballoc.c:2176 [inline] ext4_mb_regular_allocator+0x851/0x18a0 fs/ext4/mballoc.c:2409 ext4_mb_new_blocks+0x6e8/0x1140 fs/ext4/mballoc.c:4997 ext4_new_meta_blocks+0x84/0x180 fs/ext4/balloc.c:679 ext4_ext_grow_indepth fs/ext4/extents.c:1276 [inline] ext4_ext_create_new_leaf fs/ext4/extents.c:1380 [inline] ext4_ext_insert_extent+0x9d2/0x2b50 fs/ext4/extents.c:2054 ext4_split_extent_at+0x6f2/0xb40 fs/ext4/extents.c:3208 ext4_force_split_extent_at fs/ext4/extents.c:305 [inline] ext4_swap_extents+0xd76/0x13a0 fs/ext4/extents.c:5664 move_extent_per_page+0x1309/0x1590 fs/ext4/move_extent.c:339 ext4_move_extents+0xab2/0xc00 fs/ext4/move_extent.c:673 __ext4_ioctl fs/ext4/ioctl.c:988 [inline] ext4_ioctl+0x2120/0x3540 fs/ext4/ioctl.c:1319 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 17189 Comm: syz-executor.3 Not tainted 5.10.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================