syzbot

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BUG: KCSAN: data-race in ext4_mb_good_group / mb_mark_used

write to 0xffff888103819b54 of 4 bytes by task 1827 on cpu 1:
 mb_mark_used+0x13b/0xc50 fs/ext4/mballoc.c:1947
 ext4_mb_use_best_found+0x102/0x300 fs/ext4/mballoc.c:2019
 ext4_mb_check_limits fs/ext4/mballoc.c:2091 [inline]
 ext4_mb_complex_scan_group+0x81f/0x880 fs/ext4/mballoc.c:2371
 ext4_mb_regular_allocator+0x19c8/0x24a0 fs/ext4/mballoc.c:2778
 ext4_mb_new_blocks+0x78c/0x1ee0 fs/ext4/mballoc.c:5582
 ext4_ext_map_blocks+0x1658/0x2110 fs/ext4/extents.c:4282
 ext4_map_blocks+0x757/0xfa0 fs/ext4/inode.c:638
 ext4_getblk+0xc6/0x3e0 fs/ext4/inode.c:849
 ext4_bread+0x28/0x100 fs/ext4/inode.c:902
 ext4_append+0xd1/0x1c0 fs/ext4/namei.c:67
 ext4_init_new_dir+0x177/0x500 fs/ext4/namei.c:2893
 ext4_mkdir+0x329/0x760 fs/ext4/namei.c:2939
 vfs_mkdir+0x216/0x320 fs/namei.c:3933
 do_mkdirat+0x12e/0x2c0 fs/namei.c:3959
 __do_sys_mkdir fs/namei.c:3979 [inline]
 __se_sys_mkdir fs/namei.c:3977 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3977
 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 0xffff888103819b54 of 4 bytes by task 1815 on cpu 0:
 ext4_mb_good_group+0x136/0x370 fs/ext4/mballoc.c:2432
 ext4_mb_good_group_nolock fs/ext4/mballoc.c:2545 [inline]
 ext4_mb_regular_allocator+0x15c2/0x24a0 fs/ext4/mballoc.c:2747
 ext4_mb_new_blocks+0x78c/0x1ee0 fs/ext4/mballoc.c:5582
 ext4_ext_map_blocks+0x1658/0x2110 fs/ext4/extents.c:4282
 ext4_map_blocks+0x757/0xfa0 fs/ext4/inode.c:638
 ext4_getblk+0xc6/0x3e0 fs/ext4/inode.c:849
 ext4_bread+0x28/0x100 fs/ext4/inode.c:902
 ext4_append+0xd1/0x1c0 fs/ext4/namei.c:67
 ext4_init_new_dir+0x177/0x500 fs/ext4/namei.c:2893
 ext4_mkdir+0x329/0x760 fs/ext4/namei.c:2939
 vfs_mkdir+0x216/0x320 fs/namei.c:3933
 do_mkdirat+0x12e/0x2c0 fs/namei.c:3959
 __do_sys_mkdir fs/namei.c:3979 [inline]
 __se_sys_mkdir fs/namei.c:3977 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3977
 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: 0x000006e6 -> 0x000006e5

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1815 Comm: syz-executor.1 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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