================================================================== BUG: KCSAN: data-race in folios_put_refs / need_mlock_drain write to 0xffff888237d26a10 of 1 bytes by task 28035 on cpu 1: folio_batch_reinit include/linux/pagevec.h:50 [inline] folios_put_refs+0x285/0x2d0 mm/swap.c:986 folios_put include/linux/mm.h:1415 [inline] mlock_folio_batch+0x1a5b/0x1a70 mm/mlock.c:209 mlock_new_folio+0x1a3/0x200 mm/mlock.c:282 folio_add_lru_vma+0x5f/0x70 mm/swap.c:522 do_anonymous_page mm/memory.c:5138 [inline] do_pte_missing mm/memory.c:4249 [inline] handle_pte_fault mm/memory.c:6089 [inline] __handle_mm_fault mm/memory.c:6232 [inline] handle_mm_fault+0x27e0/0x2be0 mm/memory.c:6401 faultin_page mm/gup.c:1186 [inline] __get_user_pages+0x1036/0x1fb0 mm/gup.c:1488 populate_vma_page_range mm/gup.c:1926 [inline] __mm_populate+0x243/0x3a0 mm/gup.c:2029 mm_populate include/linux/mm.h:3348 [inline] __do_sys_mlockall mm/mlock.c:771 [inline] __se_sys_mlockall+0x368/0x3d0 mm/mlock.c:747 __x64_sys_mlockall+0x1f/0x30 mm/mlock.c:747 x64_sys_call+0x290a/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:152 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 0xffff888237d26a10 of 1 bytes by task 22052 on cpu 0: folio_batch_count include/linux/pagevec.h:56 [inline] need_mlock_drain+0x30/0x50 mm/mlock.c:235 cpu_needs_drain mm/swap.c:779 [inline] __lru_add_drain_all+0x220/0x3f0 mm/swap.c:867 lru_add_drain_all+0x10/0x20 mm/swap.c:883 invalidate_bdev+0x47/0x70 block/bdev.c:101 ext4_put_super+0x624/0x7d0 fs/ext4/super.c:1339 generic_shutdown_super+0xe6/0x210 fs/super.c:643 kill_block_super+0x2a/0x70 fs/super.c:1753 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391 deactivate_locked_super+0x75/0x1c0 fs/super.c:474 deactivate_super+0x97/0xa0 fs/super.c:507 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1417 __cleanup_mnt+0x19/0x20 fs/namespace.c:1424 task_work_run+0x12e/0x1a0 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x1f -> 0x08 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 22052 Comm: syz-executor Not tainted 6.15.0-syzkaller-13659-g5b032cac6225 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ==================================================================