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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237c25ee8 of 1 bytes by task 4607 on cpu 0:
 folio_batch_add include/linux/pagevec.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa5/0x1f0 mm/swap.c:511
 shmem_alloc_and_add_folio mm/shmem.c:1969 [inline]
 shmem_get_folio_gfp+0x7ab/0xd60 mm/shmem.c:2533
 shmem_fault+0xf6/0x250 mm/shmem.c:2734
 __do_fault+0xbc/0x200 mm/memory.c:5280
 do_read_fault mm/memory.c:5698 [inline]
 do_fault mm/memory.c:5832 [inline]
 do_pte_missing mm/memory.c:4361 [inline]
 handle_pte_fault mm/memory.c:6177 [inline]
 __handle_mm_fault mm/memory.c:6318 [inline]
 handle_mm_fault+0xf78/0x2be0 mm/memory.c:6487
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x102a/0x1ed0 mm/gup.c:1428
 populate_vma_page_range mm/gup.c:1860 [inline]
 __mm_populate+0x243/0x3a0 mm/gup.c:1963
 mm_populate include/linux/mm.h:3471 [inline]
 vm_mmap_pgoff+0x232/0x2e0 mm/util.c:586
 ksys_mmap_pgoff+0xc2/0x310 mm/mmap.c:604
 x64_sys_call+0x14a3/0x3000 arch/x86/include/generated/asm/syscalls_64.h:10
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c25ee8 of 1 bytes by task 4606 on cpu 1:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:780 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:877
 lru_add_drain_all+0x10/0x20 mm/swap.c:893
 memfd_wait_for_pins+0x33f/0x620 mm/memfd.c:145
 memfd_add_seals mm/memfd.c:265 [inline]
 memfd_fcntl+0x33d/0x400 mm/memfd.c:299
 do_fcntl+0x64f/0xdf0 fs/fcntl.c:545
 __do_sys_fcntl fs/fcntl.c:589 [inline]
 __se_sys_fcntl+0xb1/0x120 fs/fcntl.c:574
 __x64_sys_fcntl+0x43/0x50 fs/fcntl.c:574
 x64_sys_call+0x29a4/0x3000 arch/x86/include/generated/asm/syscalls_64.h:73
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0e -> 0x10

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4606 Comm: syz.1.375 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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