syzbot

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BUG: KCSAN: data-race in other_inode_match / ovl_inuse_trylock

write to 0xffff888128de5180 of 8 bytes by task 11145 on cpu 0:
 ovl_inuse_trylock+0x87/0xc0 fs/overlayfs/util.c:620
 ovl_get_upper fs/overlayfs/super.c:1064 [inline]
 ovl_fill_super+0xa2e/0x2875 fs/overlayfs/super.c:1638
 mount_nodev+0x6b/0xf0 fs/super.c:1463
 ovl_mount+0x36/0x50 fs/overlayfs/super.c:1743
 legacy_get_tree+0x7e/0xf0 fs/fs_context.c:622
 vfs_get_tree+0x56/0x1a0 fs/super.c:1547
 do_new_mount fs/namespace.c:2822 [inline]
 do_mount+0x1004/0x14f0 fs/namespace.c:3107
 __do_sys_mount fs/namespace.c:3316 [inline]
 __se_sys_mount fs/namespace.c:3293 [inline]
 __x64_sys_mount+0x12d/0x1a0 fs/namespace.c:3293
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888128de5180 of 8 bytes by task 45 on cpu 1:
 other_inode_match+0x6b/0x5c0 fs/ext4/inode.c:4849
 find_inode_nowait+0x135/0x160 fs/inode.c:1445
 ext4_update_other_inodes_time fs/ext4/inode.c:4897 [inline]
 ext4_do_update_inode fs/ext4/inode.c:5023 [inline]
 ext4_mark_iloc_dirty+0x12a8/0x1580 fs/ext4/inode.c:5578
 ext4_mark_inode_dirty+0xe9/0x420 fs/ext4/inode.c:5771
 ext4_convert_unwritten_extents+0x2c3/0x3b0 fs/ext4/extents.c:4972
 ext4_convert_unwritten_io_end_vec+0xe7/0x1b0 fs/ext4/extents.c:4999
 ext4_end_io_end fs/ext4/page-io.c:189 [inline]
 ext4_do_flush_completed_IO fs/ext4/page-io.c:262 [inline]
 ext4_end_io_rsv_work+0x2de/0x430 fs/ext4/page-io.c:276
 process_one_work+0x413/0x8f0 kernel/workqueue.c:2264
 worker_thread+0xa0/0x800 kernel/workqueue.c:2410
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 45 Comm: kworker/u4:2 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
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