====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc2-next-20250619-syzkaller #0 Not tainted ------------------------------------------------------ syz.9.3805/26645 is trying to acquire lock: ffff88806e68cda0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff88801c704520 (sb_pagefaults#5){.+.+}-{0:0}, at: do_page_mkwrite+0x14a/0x310 mm/memory.c:3396 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#5){.+.+}-{0:0}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline] percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] __sb_start_write include/linux/fs.h:1798 [inline] sb_start_pagefault include/linux/fs.h:1963 [inline] ocfs2_page_mkwrite+0x1da/0xc40 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x14a/0x310 mm/memory.c:3396 do_shared_fault mm/memory.c:5684 [inline] do_fault mm/memory.c:5746 [inline] do_pte_missing mm/memory.c:4269 [inline] handle_pte_fault mm/memory.c:6087 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6230 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __might_fault+0xcc/0x130 mm/memory.c:6989 _inline_copy_to_user include/linux/uaccess.h:192 [inline] _copy_to_user+0x2c/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:225 [inline] fiemap_fill_next_extent+0x1c0/0x390 fs/ioctl.c:145 ocfs2_fiemap_inline fs/ocfs2/extent_map.c:735 [inline] ocfs2_fiemap+0x9dc/0xc90 fs/ocfs2/extent_map.c:772 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x16d0/0x1990 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x14a/0x310 mm/memory.c:3396 do_shared_fault mm/memory.c:5684 [inline] do_fault mm/memory.c:5746 [inline] do_pte_missing mm/memory.c:4269 [inline] handle_pte_fault mm/memory.c:6087 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6230 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 other info that might help us debug this: Chain exists of: &ocfs2_file_ip_alloc_sem_key --> &mm->mmap_lock --> sb_pagefaults#5 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#5); lock(&mm->mmap_lock); lock(sb_pagefaults#5); lock(&ocfs2_file_ip_alloc_sem_key); *** DEADLOCK *** 2 locks held by syz.9.3805/26645: #0: ffff88801a4757e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:431 [inline] #0: ffff88801a4757e0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:188 [inline] #0: ffff88801a4757e0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x300 mm/mmap_lock.c:248 #1: ffff88801c704520 (sb_pagefaults#5){.+.+}-{0:0}, at: do_page_mkwrite+0x14a/0x310 mm/memory.c:3396 stack backtrace: CPU: 0 UID: 0 PID: 26645 Comm: syz.9.3805 Not tainted 6.16.0-rc2-next-20250619-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3168 [inline] check_prevs_add kernel/locking/lockdep.c:3287 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x14a/0x310 mm/memory.c:3396 do_shared_fault mm/memory.c:5684 [inline] do_fault mm/memory.c:5746 [inline] do_pte_missing mm/memory.c:4269 [inline] handle_pte_fault mm/memory.c:6087 [inline] __handle_mm_fault+0x1a60/0x5620 mm/memory.c:6230 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399 do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387 handle_page_fault arch/x86/mm/fault.c:1476 [inline] exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fe549b56698 Code: fc 89 37 c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 c5 fa 7f 07 c5 fa 7f 4c 17 f0 c3 66 0f 1f 84 00 00 00 00 00 48 8b 4c 16 f8 48 8b 36 <48> 89 37 48 89 4c 17 f8 c3 c5 fe 6f 54 16 e0 c5 fe 6f 5c 16 c0 c5 RSP: 002b:00007ffd4849d4c8 EFLAGS: 00010206 RAX: 0000200000000140 RBX: 0000000000000004 RCX: 0023706f6f6c2f76 RDX: 000000000000000b RSI: 6f6f6c2f7665642f RDI: 0000200000000140 RBP: 00007fe549db7ba0 R08: 00007fe549a00000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 00007fe549db5fac R13: 00007ffd4849d5c0 R14: fffffffffffffffe R15: 00007ffd4849d5e0 ocfs2: Unmounting device (7,9) on (node local)