syzbot

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BUG: KCSAN: data-race in delete_from_page_cache_batch / migrate_pages

write to 0xffffea0005206b98 of 8 bytes by task 25432 on cpu 0:
 page_cache_delete_batch mm/filemap.c:329 [inline]
 delete_from_page_cache_batch+0x2fc/0x690 mm/filemap.c:360
 truncate_inode_pages_range+0x1d5/0xac0 mm/truncate.c:330
 truncate_inode_pages mm/truncate.c:428 [inline]
 truncate_pagecache+0x4f/0x70 mm/truncate.c:754
 ext4_setattr+0xa21/0xec0 fs/ext4/inode.c:5500
 notify_change+0x8a3/0xa80 fs/attr.c:398
 do_truncate+0xe8/0x130 fs/open.c:64
 handle_truncate fs/namei.c:3020 [inline]
 do_open fs/namei.c:3371 [inline]
 path_openat+0x1a79/0x20b0 fs/namei.c:3500
 do_filp_open+0xd9/0x1f0 fs/namei.c:3527
 do_sys_openat2+0xa3/0x250 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_openat fs/open.c:1219 [inline]
 __se_sys_openat fs/open.c:1214 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1214
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffea0005206b98 of 8 bytes by task 25441 on cpu 1:
 __PageMovable include/linux/page-flags.h:489 [inline]
 __unmap_and_move mm/migrate.c:1028 [inline]
 unmap_and_move mm/migrate.c:1200 [inline]
 migrate_pages+0x3cb/0x14e0 mm/migrate.c:1472
 do_mbind+0xdd9/0xfc0 mm/mempolicy.c:1357
 kernel_mbind mm/mempolicy.c:1478 [inline]
 __do_sys_mbind mm/mempolicy.c:1485 [inline]
 __se_sys_mbind mm/mempolicy.c:1481 [inline]
 __x64_sys_mbind+0x142/0x170 mm/mempolicy.c:1481
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 25441 Comm: syz-executor.0 Not tainted 5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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