syzbot

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BUG: KCSAN: data-race in mlock_pagevec / need_mlock_page_drain

write to 0xffff888237d27f18 of 1 bytes by task 14445 on cpu 1:
 pagevec_reinit include/linux/pagevec.h:46 [inline]
 mlock_pagevec+0x13a/0x150 mm/mlock.c:210
 munlock_page+0x25f/0x2a0 mm/mlock.c:304
 munlock_vma_page mm/internal.h:539 [inline]
 page_remove_rmap+0x17e/0x220 mm/rmap.c:1467
 zap_pte_range+0x6ca/0x1560 mm/memory.c:1454
 zap_pmd_range mm/memory.c:1575 [inline]
 zap_pud_range mm/memory.c:1604 [inline]
 zap_p4d_range mm/memory.c:1625 [inline]
 unmap_page_range+0x3ac/0x730 mm/memory.c:1646
 unmap_single_vma+0x157/0x230 mm/memory.c:1694
 unmap_vmas+0xdf/0x1a0 mm/memory.c:1731
 exit_mmap+0x11f/0x380 mm/mmap.c:3116
 __mmput+0x27/0x1b0 kernel/fork.c:1187
 mmput+0x3d/0x50 kernel/fork.c:1208
 exit_mm+0xdb/0x170 kernel/exit.c:510
 do_exit+0x525/0x16e0 kernel/exit.c:782
 __x64_sys_exit_group+0x0/0x20 kernel/exit.c:925
 __do_sys_exit_group kernel/exit.c:936 [inline]
 __se_sys_exit_group kernel/exit.c:934 [inline]
 __x64_sys_exit_group+0x1b/0x20 kernel/exit.c:934
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888237d27f18 of 1 bytes by task 14452 on cpu 0:
 pagevec_count include/linux/pagevec.h:51 [inline]
 need_mlock_page_drain+0x2c/0x50 mm/mlock.c:236
 cpu_needs_drain mm/swap.c:779 [inline]
 __lru_add_drain_all+0x328/0x450 mm/swap.c:867
 lru_cache_disable+0x1b/0x20 mm/swap.c:920
 do_pages_move mm/migrate.c:1759 [inline]
 kernel_move_pages mm/migrate.c:2008 [inline]
 __do_sys_move_pages mm/migrate.c:2022 [inline]
 __se_sys_move_pages+0x2e6/0xcf0 mm/migrate.c:2017
 __x64_sys_move_pages+0x74/0x80 mm/migrate.c:2017
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14452 Comm: syz-executor.0 Not tainted 6.0.0-rc2-syzkaller-00248-ge022620b5d05-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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