KCSAN: data-race in __ext4_update_other_inode_time / __ext4_update_other_inode

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __ext4_update_other_inode_time / __ext4_update_other_inode_time ext4				4	1501d	1512d	0/28	auto-closed as invalid on 2021/01/22 10:57

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BUG: KCSAN: data-race in __ext4_update_other_inode_time / __ext4_update_other_inode_time

write to 0xffff888014c2c7b8 of 8 bytes by task 8458 on cpu 1:
 __ext4_update_other_inode_time+0xc1/0x550 fs/ext4/inode.c:4975
 ext4_update_other_inodes_time fs/ext4/inode.c:5011 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5140 [inline]
 ext4_mark_iloc_dirty+0x11b6/0x16f0 fs/ext4/inode.c:5725
 __ext4_mark_inode_dirty+0x4d6/0x5e0 fs/ext4/inode.c:5919
 ext4_rmdir+0x8eb/0x970 fs/ext4/namei.c:3170
 vfs_rmdir+0x135/0x2a0 fs/namei.c:3715
 do_rmdir+0x16e/0x300 fs/namei.c:3776
 __do_sys_rmdir fs/namei.c:3794 [inline]
 __se_sys_rmdir fs/namei.c:3792 [inline]
 __x64_sys_rmdir+0x2c/0x30 fs/namei.c:3792
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888014c2c7b8 of 8 bytes by task 8456 on cpu 0:
 __ext4_update_other_inode_time+0x45/0x550 fs/ext4/inode.c:4964
 ext4_update_other_inodes_time fs/ext4/inode.c:5011 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5140 [inline]
 ext4_mark_iloc_dirty+0x11b6/0x16f0 fs/ext4/inode.c:5725
 __ext4_mark_inode_dirty+0x4d6/0x5e0 fs/ext4/inode.c:5919
 ext4_rmdir+0x8eb/0x970 fs/ext4/namei.c:3170
 vfs_rmdir+0x135/0x2a0 fs/namei.c:3715
 do_rmdir+0x16e/0x300 fs/namei.c:3776
 __do_sys_rmdir fs/namei.c:3794 [inline]
 __se_sys_rmdir fs/namei.c:3792 [inline]
 __x64_sys_rmdir+0x2c/0x30 fs/namei.c:3792
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8456 Comm: syz-executor.3 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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