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KCSAN: data-race in folios_put_refs / need_mlock_drain (2)

Status: upstream: reported on 2024/11/04 11:35
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+716d26ee203ef06cc21d@syzkaller.appspotmail.com
First crash: 242d, last: 3d02h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] KCSAN: data-race in folios_put_refs / need_mlock_drain (2) 0 (1) 2024/11/04 11:35
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in folios_put_refs / need_mlock_drain mm 20 291d 380d 0/29 auto-obsoleted due to no activity on 2024/10/20 22:05

Sample crash report:
EXT4-fs (loop0): unmounting filesystem 00000000-0000-0000-0000-000000000000.
==================================================================
BUG: KCSAN: data-race in folios_put_refs / need_mlock_drain

write to 0xffff888237d26a10 of 1 bytes by task 4601 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
 munlock_folio+0xd2/0x120 mm/mlock.c:303
 munlock_vma_folio mm/internal.h:1023 [inline]
 __folio_remove_rmap mm/rmap.c:1787 [inline]
 folio_remove_rmap_ptes+0x197/0x1a0 mm/rmap.c:1804
 zap_present_folio_ptes mm/memory.c:1529 [inline]
 zap_present_ptes mm/memory.c:1590 [inline]
 do_zap_pte_range mm/memory.c:1691 [inline]
 zap_pte_range mm/memory.c:1735 [inline]
 zap_pmd_range mm/memory.c:1827 [inline]
 zap_pud_range mm/memory.c:1856 [inline]
 zap_p4d_range mm/memory.c:1877 [inline]
 unmap_page_range+0x14f6/0x2740 mm/memory.c:1898
 unmap_single_vma mm/memory.c:1941 [inline]
 unmap_vmas+0x23d/0x3a0 mm/memory.c:1985
 exit_mmap+0x1b0/0x6c0 mm/mmap.c:1284
 __mmput+0x28/0x1c0 kernel/fork.c:1121
 mmput+0x40/0x50 kernel/fork.c:1144
 exit_mm+0xe4/0x190 kernel/exit.c:581
 do_exit+0x417/0x1590 kernel/exit.c:952
 do_group_exit+0x139/0x140 kernel/exit.c:1105
 __do_sys_exit_group kernel/exit.c:1116 [inline]
 __se_sys_exit_group kernel/exit.c:1114 [inline]
 __x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1114
 x64_sys_call+0x2fa4/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:232
 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 3311 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+0xe3/0x210 fs/super.c:643
 kill_block_super+0x2a/0x70 fs/super.c:1755
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391
 deactivate_locked_super+0x72/0x1c0 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+0x131/0x1a0 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 -> 0x19

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3311 Comm: syz-executor Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================

Crashes (21):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/30 22:33 upstream d0b3b7b22dfa 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/06/29 21:13 upstream dfba48a70cb6 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/06/07 20:16 upstream 5b032cac6225 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/06/01 19:39 upstream bb1556ec9464 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/04/29 02:28 upstream f15d97df5afa aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/04/16 23:10 upstream c62f4b82d571 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/04/11 07:20 upstream 900241a5cc15 94486846 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/03/23 07:21 upstream 183601b78a9b 4e8d3850 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/03/04 08:42 upstream 99fa936e8e4f c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/03/02 19:29 upstream b91872c56940 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/02/13 17:24 upstream 4dc1d1bec898 a98a8417 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/01/27 05:09 upstream c2da8b3f914f 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2025/01/10 01:11 upstream 643e2e259c2b 9220929f .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/12/12 16:37 upstream 231825b2e1ff 530e80f8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/12/06 18:48 upstream b8f52214c61a 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/12/04 23:05 upstream feffde684ac2 b50eb251 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/12/03 10:29 upstream cdd30ebb1b9f 578925bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/11/25 13:20 upstream 9f16d5e6f220 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/11/23 18:46 upstream 06afb0f36106 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/11/12 11:54 upstream 2d5404caa8c7 75bb1b32 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
2024/11/03 19:44 upstream a33ab3f94f51 f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in folios_put_refs / need_mlock_drain
* Struck through repros no longer work on HEAD.