==================================================================
BUG: KCSAN: data-race in mb_free_blocks / mb_update_avg_fragment_size

write to 0xffff8881013e2b54 of 4 bytes by task 1784 on cpu 0:
 mb_free_blocks+0x156/0xb40 fs/ext4/mballoc.c:1798
 ext4_free_blocks+0x1418/0x1b50 fs/ext4/mballoc.c:5988
 ext4_remove_blocks+0x61a/0x800 fs/ext4/extents.c:2498
 ext4_ext_rm_leaf+0x670/0xd20 fs/ext4/extents.c:2664
 ext4_ext_remove_space+0x901/0x1300 fs/ext4/extents.c:2912
 ext4_ext_truncate+0xfe/0x170 fs/ext4/extents.c:4370
 ext4_truncate+0x76e/0xa80 fs/ext4/inode.c:4262
 ext4_evict_inode+0xa54/0xdb0 fs/ext4/inode.c:288
 evict+0x1c8/0x3c0 fs/inode.c:584
 iput_final fs/inode.c:1660 [inline]
 iput+0x433/0x590 fs/inode.c:1686
 dentry_unlink_inode+0x23a/0x260 fs/dcache.c:376
 d_delete+0x78/0xe0 fs/dcache.c:2505
 vfs_rmdir+0x2a6/0x2c0 fs/namei.c:3909
 do_rmdir+0x14a/0x2e0 fs/namei.c:3958
 __do_sys_rmdir fs/namei.c:3976 [inline]
 __se_sys_rmdir fs/namei.c:3974 [inline]
 __x64_sys_rmdir+0x2c/0x30 fs/namei.c:3974
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881013e2b54 of 4 bytes by task 1715 on cpu 1:
 ext4_mb_avg_fragment_size_cmp fs/ext4/mballoc.c:835 [inline]
 ext4_mb_rb_insert fs/ext4/mballoc.c:811 [inline]
 mb_update_avg_fragment_size+0x184/0x260 fs/ext4/mballoc.c:859
 mb_mark_used+0xae0/0xc50 fs/ext4/mballoc.c:1993
 ext4_mb_use_best_found+0x102/0x320 fs/ext4/mballoc.c:2014
 ext4_mb_find_by_goal+0x5c3/0x890 fs/ext4/mballoc.c:2226
 ext4_mb_regular_allocator+0x11c/0x2520 fs/ext4/mballoc.c:2635
 ext4_mb_new_blocks+0x762/0x1f90 fs/ext4/mballoc.c:5514
 ext4_ext_map_blocks+0x1569/0x1f00 fs/ext4/extents.c:4238
 ext4_map_blocks+0x70d/0xef0 fs/ext4/inode.c:638
 ext4_alloc_file_blocks+0x271/0x720 fs/ext4/extents.c:4425
 ext4_fallocate+0x2a7/0x4d0 fs/ext4/extents.c:4705
 vfs_fallocate+0x463/0x660 fs/open.c:311
 ksys_fallocate fs/open.c:334 [inline]
 __do_sys_fallocate fs/open.c:342 [inline]
 __se_sys_fallocate fs/open.c:340 [inline]
 __x64_sys_fallocate+0x75/0xc0 fs/open.c:340
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000058fa -> 0x000058fb

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1715 Comm: syz-executor.1 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 0
CPU: 1 PID: 1715 Comm: syz-executor.1 Not tainted 5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x137/0x19d lib/dump_stack.c:120
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail+0x23c/0x250 lib/fault-inject.c:146
 __should_failslab+0x81/0x90 mm/failslab.c:33
 should_failslab+0x5/0x20 mm/slab_common.c:1295
 slab_pre_alloc_hook mm/slab.h:499 [inline]
 slab_alloc mm/slab.c:3306 [inline]
 kmem_cache_alloc+0x46/0x2f0 mm/slab.c:3507
 kmem_cache_zalloc include/linux/slab.h:676 [inline]
 ext4_mb_pa_alloc fs/ext4/mballoc.c:4974 [inline]
 ext4_mb_new_blocks+0x70f/0x1f90 fs/ext4/mballoc.c:5509
 ext4_ext_map_blocks+0x1569/0x1f00 fs/ext4/extents.c:4238
 ext4_map_blocks+0x70d/0xef0 fs/ext4/inode.c:638
 ext4_alloc_file_blocks+0x271/0x720 fs/ext4/extents.c:4425
 ext4_fallocate+0x2a7/0x4d0 fs/ext4/extents.c:4705
 vfs_fallocate+0x463/0x660 fs/open.c:311
 ksys_fallocate fs/open.c:334 [inline]
 __do_sys_fallocate fs/open.c:342 [inline]
 __se_sys_fallocate fs/open.c:340 [inline]
 __x64_sys_fallocate+0x75/0xc0 fs/open.c:340
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007feb0bad7188 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007feb0bad71d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000010000101 R11: 0000000000000246 R12: 0000000000000002
R13: 00007ffd1437465f R14: 00007feb0bad7300 R15: 0000000000022000