====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 Not tainted ------------------------------------------------------ syz.7.464/9437 is trying to acquire lock: ffff0000c16f94a0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_page_mkwrite+0x340/0xbf4 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff0000f7556520 (sb_pagefaults#5){.+.+}-{0:0}, at: do_page_mkwrite+0x138/0x2b8 mm/memory.c:3378 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#5){.+.+}-{0:0}: 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:1793 [inline] sb_start_pagefault include/linux/fs.h:1958 [inline] ocfs2_page_mkwrite+0x1b0/0xbf4 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x138/0x2b8 mm/memory.c:3378 do_shared_fault mm/memory.c:5686 [inline] do_fault mm/memory.c:5748 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6089 [inline] __handle_mm_fault mm/memory.c:6232 [inline] handle_mm_fault+0x1aa0/0x4d38 mm/memory.c:6401 do_page_fault+0x8d8/0x1554 arch/arm64/mm/fault.c:690 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:919 el0_da+0x64/0x160 arch/arm64/kernel/entry-common.c:627 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:789 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #1 (&mm->mmap_lock){++++}-{4:4}: __might_fault+0xc4/0x124 mm/memory.c:6991 _inline_copy_to_user include/linux/uaccess.h:192 [inline] copy_to_user include/linux/uaccess.h:223 [inline] fiemap_fill_next_extent+0x17c/0x3f0 fs/ioctl.c:145 ocfs2_fiemap+0x648/0x9c4 fs/ocfs2/extent_map.c:806 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1560/0x1cd8 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0xe4/0x1c4 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #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 kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5240 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871 down_write+0x50/0xc0 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x340/0xbf4 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x138/0x2b8 mm/memory.c:3378 do_shared_fault mm/memory.c:5686 [inline] do_fault mm/memory.c:5748 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6089 [inline] __handle_mm_fault mm/memory.c:6232 [inline] handle_mm_fault+0x1aa0/0x4d38 mm/memory.c:6401 do_page_fault+0x8d8/0x1554 arch/arm64/mm/fault.c:690 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:919 el0_da+0x64/0x160 arch/arm64/kernel/entry-common.c:627 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:789 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 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.7.464/9437: #0: ffff0000c2c001d0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:431 [inline] #0: ffff0000c2c001d0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:188 [inline] #0: ffff0000c2c001d0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x38/0x2d8 mm/mmap_lock.c:248 #1: ffff0000f7556520 (sb_pagefaults#5){.+.+}-{0:0}, at: do_page_mkwrite+0x138/0x2b8 mm/memory.c:3378 stack backtrace: CPU: 0 UID: 0 PID: 9437 Comm: syz.7.464 Not tainted 6.16.0-rc2-syzkaller-g9aa9b43d689e #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:501 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x324/0x32c kernel/locking/lockdep.c:2046 check_noncircular+0x154/0x174 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 kernel/locking/lockdep.c:3911 [inline] __lock_acquire+0x1774/0x30a4 kernel/locking/lockdep.c:5240 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871 down_write+0x50/0xc0 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x340/0xbf4 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x138/0x2b8 mm/memory.c:3378 do_shared_fault mm/memory.c:5686 [inline] do_fault mm/memory.c:5748 [inline] do_pte_missing mm/memory.c:4251 [inline] handle_pte_fault mm/memory.c:6089 [inline] __handle_mm_fault mm/memory.c:6232 [inline] handle_mm_fault+0x1aa0/0x4d38 mm/memory.c:6401 do_page_fault+0x8d8/0x1554 arch/arm64/mm/fault.c:690 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:919 el0_da+0x64/0x160 arch/arm64/kernel/entry-common.c:627 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:789 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600