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BUG: KCSAN: data-race in ext4_mb_find_by_goal / mb_free_blocks

write to 0xffff88810200a6d4 of 4 bytes by task 13189 on cpu 1:
 mb_free_blocks+0x156/0xb40 fs/ext4/mballoc.c:1798
 ext4_free_blocks+0x1418/0x1b50 fs/ext4/mballoc.c:5989
 ext4_remove_blocks+0x61a/0x800 fs/ext4/extents.c:2502
 ext4_ext_rm_leaf+0x670/0xd20 fs/ext4/extents.c:2668
 ext4_ext_remove_space+0x901/0x1300 fs/ext4/extents.c:2916
 ext4_ext_truncate+0xfe/0x170 fs/ext4/extents.c:4377
 ext4_truncate+0x76e/0xa80 fs/ext4/inode.c:4262
 ext4_truncate_failed_write fs/ext4/truncate.h:20 [inline]
 ext4_handle_inode_extension fs/ext4/file.c:358 [inline]
 ext4_dio_write_iter fs/ext4/file.c:574 [inline]
 ext4_file_write_iter+0x106c/0x11d0 fs/ext4/file.c:678
 call_write_iter include/linux/fs.h:2114 [inline]
 aio_write+0x287/0x360 fs/aio.c:1578
 __io_submit_one fs/aio.c:1837 [inline]
 io_submit_one+0x82f/0x1350 fs/aio.c:1880
 __do_sys_io_submit fs/aio.c:1939 [inline]
 __se_sys_io_submit+0xf5/0x260 fs/aio.c:1909
 __x64_sys_io_submit+0x3f/0x50 fs/aio.c:1909
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88810200a6d4 of 4 bytes by task 13206 on cpu 0:
 ext4_mb_find_by_goal+0x129/0x890 fs/ext4/mballoc.c:2203
 ext4_mb_regular_allocator+0x11c/0x2520 fs/ext4/mballoc.c:2636
 ext4_mb_new_blocks+0x762/0x1f90 fs/ext4/mballoc.c:5515
 ext4_ext_map_blocks+0x1569/0x1f00 fs/ext4/extents.c:4245
 ext4_map_blocks+0x70d/0xef0 fs/ext4/inode.c:638
 ext4_alloc_file_blocks+0x271/0x720 fs/ext4/extents.c:4432
 ext4_fallocate+0x2a7/0x4d0 fs/ext4/extents.c:4712
 vfs_fallocate+0x463/0x660 fs/open.c:311
 file_ioctl fs/ioctl.c:497 [inline]
 do_vfs_ioctl+0x1322/0x1410 fs/ioctl.c:1048
 __do_sys_ioctl fs/ioctl.c:1067 [inline]
 __se_sys_ioctl+0x83/0x140 fs/ioctl.c:1055
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000d38 -> 0x000014d2

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13206 Comm: syz-executor.1 Not tainted 5.14.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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