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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237c26528 of 1 bytes by task 26534 on cpu 0:
 folio_batch_add include/linux/folio_batch.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:229 [inline]
 folio_add_lru+0xa4/0x250 mm/swap.c:562
 migrate_folio_move mm/migrate.c:1404 [inline]
 migrate_folios_move mm/migrate.c:1738 [inline]
 migrate_pages_batch+0x135b/0x1f90 mm/migrate.c:1994
 migrate_pages_sync mm/migrate.c:2024 [inline]
 migrate_pages+0x1073/0x1890 mm/migrate.c:2133
 do_mbind mm/mempolicy.c:1614 [inline]
 kernel_mbind mm/mempolicy.c:1757 [inline]
 __do_sys_mbind mm/mempolicy.c:1831 [inline]
 __se_sys_mbind+0xc9c/0xdd0 mm/mempolicy.c:1827
 __x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1827
 x64_sys_call+0x2b72/0x3020 arch/x86/include/generated/asm/syscalls_64.h:238
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26528 of 1 bytes by task 26525 on cpu 1:
 folio_batch_count include/linux/folio_batch.h:56 [inline]
 cpu_needs_drain mm/swap.c:831 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:928
 lru_cache_disable+0x1f/0x30 mm/swap.c:981
 do_mbind mm/mempolicy.c:1531 [inline]
 kernel_mbind mm/mempolicy.c:1757 [inline]
 __do_sys_mbind mm/mempolicy.c:1831 [inline]
 __se_sys_mbind+0x6cd/0xdd0 mm/mempolicy.c:1827
 __x64_sys_mbind+0x78/0x90 mm/mempolicy.c:1827
 x64_sys_call+0x2b72/0x3020 arch/x86/include/generated/asm/syscalls_64.h:238
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 26525 Comm: syz.6.6761 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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