====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0 Not tainted ------------------------------------------------------ syz.4.751/9883 is trying to acquire lock: ffff88805793cda0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff88806eb70518 (sb_pagefaults#8){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3162 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#8){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1716 [inline] sb_start_pagefault include/linux/fs.h:1881 [inline] ocfs2_page_mkwrite+0x222/0xed0 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x198/0x480 mm/memory.c:3162 do_shared_fault mm/memory.c:5358 [inline] do_fault mm/memory.c:5420 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x11fa/0x6800 mm/memory.c:5751 __handle_mm_fault mm/memory.c:5894 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6062 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (&mm->mmap_lock){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __might_fault+0xc6/0x120 mm/memory.c:6700 _inline_copy_to_user include/linux/uaccess.h:183 [inline] _copy_to_user+0x2a/0xb0 lib/usercopy.c:26 copy_to_user include/linux/uaccess.h:216 [inline] fiemap_fill_next_extent+0x235/0x410 fs/ioctl.c:145 ocfs2_fiemap+0x9f1/0xf80 fs/ocfs2/extent_map.c:796 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1bf8/0x2e40 fs/ioctl.c:841 __do_sys_ioctl fs/ioctl.c:905 [inline] __se_sys_ioctl+0x81/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&ocfs2_file_ip_alloc_sem_key){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x198/0x480 mm/memory.c:3162 do_shared_fault mm/memory.c:5358 [inline] do_fault mm/memory.c:5420 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x11fa/0x6800 mm/memory.c:5751 __handle_mm_fault mm/memory.c:5894 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6062 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 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#8 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#8); lock(&mm->mmap_lock); lock(sb_pagefaults#8); lock(&ocfs2_file_ip_alloc_sem_key); *** DEADLOCK *** 2 locks held by syz.4.751/9883: #0: ffff888028525718 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff888028525718 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6099 [inline] #0: ffff888028525718 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6159 #1: ffff88806eb70518 (sb_pagefaults#8){.+.+}-{0:0}, at: do_page_mkwrite+0x198/0x480 mm/memory.c:3162 stack backtrace: CPU: 0 UID: 0 PID: 9883 Comm: syz.4.751 Not tainted 6.12.0-rc3-syzkaller-00013-geca631b8fe80 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x346/0xed0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x198/0x480 mm/memory.c:3162 do_shared_fault mm/memory.c:5358 [inline] do_fault mm/memory.c:5420 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault+0x11fa/0x6800 mm/memory.c:5751 __handle_mm_fault mm/memory.c:5894 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6062 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f2d06345a98 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:00007ffdb8327d08 EFLAGS: 00010246 RAX: 0000000020000040 RBX: 0000000000000004 RCX: 0031656c69662f2e RDX: 0000000000000008 RSI: 0031656c69662f2e RDI: 0000000020000040 RBP: 00007f2d06537a80 R08: 00007f2d06200000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 0000000000047d8e R13: 00007ffdb8327e10 R14: 0000000000000032 R15: fffffffffffffffe