syzbot

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BUG: KCSAN: data-race in ext4_mb_regular_allocator / mb_mark_used

write to 0xffff888101bde9d4 of 4 bytes by task 20625 on cpu 0:
 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:5582
 ext4_new_meta_blocks+0x84/0x180 fs/ext4/balloc.c:699
 ext4_ext_grow_indepth fs/ext4/extents.c:1321 [inline]
 ext4_ext_create_new_leaf fs/ext4/extents.c:1427 [inline]
 ext4_ext_insert_extent+0xa10/0x3060 fs/ext4/extents.c:2094
 ext4_split_extent_at+0x6eb/0xcd0 fs/ext4/extents.c:3248
 ext4_force_split_extent_at fs/ext4/extents.c:319 [inline]
 ext4_swap_extents+0xd7a/0x1470 fs/ext4/extents.c:5695
 move_extent_per_page fs/ext4/move_extent.c:339 [inline]
 ext4_move_extents+0x1fb1/0x2210 fs/ext4/move_extent.c:672
 __ext4_ioctl fs/ext4/ioctl.c:1285 [inline]
 ext4_ioctl+0x17b1/0x25c0 fs/ext4/ioctl.c:1578
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 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 0xffff888101bde9d4 of 4 bytes by task 20645 on cpu 1:
 ext4_mb_good_group_nolock fs/ext4/mballoc.c:2504 [inline]
 ext4_mb_regular_allocator+0xa97/0x24a0 fs/ext4/mballoc.c:2747
 ext4_mb_new_blocks+0x78c/0x1ee0 fs/ext4/mballoc.c:5582
 ext4_new_meta_blocks+0x84/0x180 fs/ext4/balloc.c:699
 ext4_ext_grow_indepth fs/ext4/extents.c:1321 [inline]
 ext4_ext_create_new_leaf fs/ext4/extents.c:1427 [inline]
 ext4_ext_insert_extent+0xa10/0x3060 fs/ext4/extents.c:2094
 ext4_split_extent_at+0x6eb/0xcd0 fs/ext4/extents.c:3248
 ext4_force_split_extent_at fs/ext4/extents.c:319 [inline]
 ext4_swap_extents+0xd7a/0x1470 fs/ext4/extents.c:5695
 move_extent_per_page fs/ext4/move_extent.c:339 [inline]
 ext4_move_extents+0x1fb1/0x2210 fs/ext4/move_extent.c:672
 __ext4_ioctl fs/ext4/ioctl.c:1285 [inline]
 ext4_ioctl+0x17b1/0x25c0 fs/ext4/ioctl.c:1578
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 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: 0x00000e1e -> 0x00000e1d

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 20645 Comm: syz-executor.3 Not tainted 5.17.0-rc2-syzkaller-00064-gc36c04c2e132 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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