syzbot

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BUG: KCSAN: data-race in dec_zone_page_state / release_pages

write to 0xffffea000465b180 of 8 bytes by task 11092 on cpu 0:
 instrument_write include/linux/instrumented.h:42 [inline]
 __clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:42 [inline]
 __ClearPageLRU include/linux/page-flags.h:337 [inline]
 release_pages+0x41c/0x8b0 mm/swap.c:940
 __pagevec_release+0xa7/0xd0 mm/swap.c:972
 pagevec_release include/linux/pagevec.h:88 [inline]
 truncate_inode_pages_range+0x517/0xf20 mm/truncate.c:370
 truncate_inode_pages mm/truncate.c:476 [inline]
 truncate_inode_pages_final+0x7d/0x90 mm/truncate.c:527
 ext4_evict_inode+0x2b7/0xe70 fs/ext4/inode.c:221
 evict+0x19f/0x470 fs/inode.c:578
 iput_final fs/inode.c:1654 [inline]
 iput+0x421/0x510 fs/inode.c:1680
 dentry_unlink_inode+0x1f3/0x210 fs/dcache.c:374
 __dentry_kill+0x28b/0x450 fs/dcache.c:579
 dentry_kill fs/dcache.c:692 [inline]
 dput+0x203/0x420 fs/dcache.c:878
 cleanup_mnt+0x265/0x2e0 fs/namespace.c:1117
 __cleanup_mnt+0x15/0x20 fs/namespace.c:1125
 task_work_run+0x8e/0x110 kernel/task_work.c:151
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
 exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffea000465b180 of 8 bytes by task 3165 on cpu 1:
 page_to_nid include/linux/mm.h:1302 [inline]
 page_zone include/linux/mm.h:1444 [inline]
 dec_zone_page_state+0x13/0x100 mm/vmstat.c:542
 test_clear_page_writeback+0x3ba/0x450 mm/page-writeback.c:2765
 end_page_writeback+0xa7/0x110 mm/filemap.c:1487
 ext4_finish_bio+0x429/0x490 fs/ext4/page-io.c:146
 ext4_release_io_end+0x98/0x200 fs/ext4/page-io.c:161
 ext4_end_io_end fs/ext4/page-io.c:195 [inline]
 ext4_do_flush_completed_IO fs/ext4/page-io.c:260 [inline]
 ext4_end_io_rsv_work+0x306/0x360 fs/ext4/page-io.c:274
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
 worker_thread+0x635/0xb90 kernel/workqueue.c:2418
 kthread+0x1fd/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 3165 Comm: kworker/u4:4 Not tainted 5.10.0-rc5-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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