syzbot

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BUG: KCSAN: data-race in lru_add_drain_all / pagevec_lru_move_fn

write to 0xffff88812bf27620 of 1 bytes by task 12737 on cpu 1:
 pagevec_reinit include/linux/pagevec.h:63 [inline]
 pagevec_lru_move_fn+0x163/0x180 mm/swap.c:216
 __pagevec_lru_add mm/swap.c:966 [inline]
 lru_add_drain_cpu+0x178/0x2e0 mm/swap.c:594
 lru_add_drain+0x35/0x80 mm/swap.c:689
 unmap_region+0x6b/0x270 mm/mmap.c:2622
 __do_munmap+0x661/0xb60 mm/mmap.c:2845
 do_munmap mm/mmap.c:2856 [inline]
 mmap_region+0x165/0xd50 mm/mmap.c:1749
 do_mmap+0x6d4/0xba0 mm/mmap.c:1577
 do_mmap_pgoff include/linux/mm.h:2353 [inline]
 __do_sys_remap_file_pages mm/mmap.c:2985 [inline]
 __se_sys_remap_file_pages mm/mmap.c:2901 [inline]
 __x64_sys_remap_file_pages+0x4af/0x560 mm/mmap.c:2901
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812bf27620 of 1 bytes by task 12738 on cpu 0:
 lru_add_drain_all+0xf5/0x350 mm/swap.c:728
 migrate_prep+0x17/0x20 mm/migrate.c:72
 do_mbind mm/mempolicy.c:1265 [inline]
 kernel_mbind+0x9e7/0xaa0 mm/mempolicy.c:1419
 __do_sys_mbind mm/mempolicy.c:1426 [inline]
 __se_sys_mbind mm/mempolicy.c:1422 [inline]
 __x64_sys_mbind+0x89/0xb0 mm/mempolicy.c:1422
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12738 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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