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BUG: KCSAN: data-race in ext4_mb_good_group / mb_mark_used

write to 0xffff88812a6e4768 of 4 bytes by task 7835 on cpu 0:
 mb_mark_used+0x894/0x940 fs/ext4/mballoc.c:1586
 ext4_mb_use_best_found+0x111/0x310 fs/ext4/mballoc.c:1645
 ext4_mb_measure_extent fs/ext4/mballoc.c:1748 [inline]
 ext4_mb_complex_scan_group+0x4ae/0x5b0 fs/ext4/mballoc.c:1978
 ext4_mb_regular_allocator+0x610/0x9d0 fs/ext4/mballoc.c:2216
 ext4_mb_new_blocks+0xdd3/0x1ca0 fs/ext4/mballoc.c:4539
 ext4_new_meta_blocks+0x175/0x200 fs/ext4/balloc.c:657
 ext4_xattr_block_set+0xec8/0x1cf0 fs/ext4/xattr.c:2068
 ext4_xattr_set_handle+0x969/0xcc0 fs/ext4/xattr.c:2404
 __ext4_set_acl+0x25a/0x360 fs/ext4/acl.c:214
 ext4_init_acl+0x1a2/0x200 fs/ext4/acl.c:293
 __ext4_new_inode+0x28f0/0x3070 fs/ext4/ialloc.c:1156
 ext4_mkdir+0x289/0x820 fs/ext4/namei.c:2763
 vfs_mkdir+0x283/0x390 fs/namei.c:3815
 ovl_do_mkdir fs/overlayfs/overlayfs.h:125 [inline]
 ovl_mkdir_real fs/overlayfs/dir.c:122 [inline]
 ovl_create_real+0x1db/0x2b0 fs/overlayfs/dir.c:169

read to 0xffff88812a6e4768 of 4 bytes by task 7832 on cpu 1:
 ext4_mb_good_group+0x1cd/0x410 fs/ext4/mballoc.c:2059
 ext4_mb_regular_allocator+0x6e1/0x9d0 fs/ext4/mballoc.c:2183
 ext4_mb_new_blocks+0xdd3/0x1ca0 fs/ext4/mballoc.c:4539
 ext4_new_meta_blocks+0x175/0x200 fs/ext4/balloc.c:657
 ext4_xattr_block_set+0xec8/0x1cf0 fs/ext4/xattr.c:2068
 ext4_xattr_set_handle+0x969/0xcc0 fs/ext4/xattr.c:2404
 __ext4_set_acl+0x25a/0x360 fs/ext4/acl.c:214
 ext4_init_acl+0x1a2/0x200 fs/ext4/acl.c:293
 __ext4_new_inode+0x28f0/0x3070 fs/ext4/ialloc.c:1156
 ext4_mkdir+0x289/0x820 fs/ext4/namei.c:2763
 vfs_mkdir+0x283/0x390 fs/namei.c:3815
 ovl_do_mkdir fs/overlayfs/overlayfs.h:125 [inline]
 ovl_mkdir_real fs/overlayfs/dir.c:122 [inline]
 ovl_create_real+0x1db/0x2b0 fs/overlayfs/dir.c:169
 ovl_workdir_create+0x299/0x3f0 fs/overlayfs/super.c:649

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7832 Comm: syz-executor.2 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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