====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc3-next-20250218-syzkaller #0 Not tainted ------------------------------------------------------ syz.6.7452/27906 is trying to acquire lock: ffff88805c0b94a0 (&ocfs2_file_ip_alloc_sem_key){++++}-{4:4}, at: ocfs2_page_mkwrite+0x34f/0xda0 fs/ocfs2/mmap.c:142 but task is already holding lock: ffff8880564c8518 (sb_pagefaults#9){.+.+}-{0:0}, at: do_page_mkwrite+0x159/0x340 mm/memory.c:3245 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#9){.+.+}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1783 [inline] sb_start_pagefault include/linux/fs.h:1948 [inline] ocfs2_page_mkwrite+0x22c/0xda0 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x159/0x340 mm/memory.c:3245 wp_page_shared mm/memory.c:3646 [inline] do_wp_page+0x23c5/0x4b50 mm/memory.c:3796 handle_pte_fault+0xfad/0x61c0 mm/memory.c:5906 __handle_mm_fault mm/memory.c:6033 [inline] handle_mm_fault+0x11ae/0x1cd0 mm/memory.c:6202 do_user_addr_fault arch/x86/mm/fault.c:1388 [inline] handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x2b9/0x920 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 -> #1 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __might_fault+0xc6/0x120 mm/memory.c:6927 _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+0x235/0x420 fs/ioctl.c:145 ocfs2_fiemap+0xa03/0x1010 fs/ocfs2/extent_map.c:806 ioctl_fiemap fs/ioctl.c:220 [inline] do_vfs_ioctl+0x1974/0x2750 fs/ioctl.c:840 __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl+0x80/0x160 fs/ioctl.c:892 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){++++}-{4:4}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x34f/0xda0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x159/0x340 mm/memory.c:3245 wp_page_shared mm/memory.c:3646 [inline] do_wp_page+0x23c5/0x4b50 mm/memory.c:3796 handle_pte_fault+0xfad/0x61c0 mm/memory.c:5906 __handle_mm_fault mm/memory.c:6033 [inline] handle_mm_fault+0x11ae/0x1cd0 mm/memory.c:6202 do_user_addr_fault arch/x86/mm/fault.c:1388 [inline] handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x2b9/0x920 arch/x86/mm/fault.c:1538 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#9 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#9); lock(&mm->mmap_lock); lock(sb_pagefaults#9); lock(&ocfs2_file_ip_alloc_sem_key); *** DEADLOCK *** 2 locks held by syz.6.7452/27906: #0: ffff888075f595e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:203 [inline] #0: ffff888075f595e0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/memory.c:6239 [inline] #0: ffff888075f595e0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6299 #1: ffff8880564c8518 (sb_pagefaults#9){.+.+}-{0:0}, at: do_page_mkwrite+0x159/0x340 mm/memory.c:3245 stack backtrace: CPU: 1 UID: 0 PID: 27906 Comm: syz.6.7452 Not tainted 6.14.0-rc3-next-20250218-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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:2076 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 down_write+0x99/0x220 kernel/locking/rwsem.c:1577 ocfs2_page_mkwrite+0x34f/0xda0 fs/ocfs2/mmap.c:142 do_page_mkwrite+0x159/0x340 mm/memory.c:3245 wp_page_shared mm/memory.c:3646 [inline] do_wp_page+0x23c5/0x4b50 mm/memory.c:3796 handle_pte_fault+0xfad/0x61c0 mm/memory.c:5906 __handle_mm_fault mm/memory.c:6033 [inline] handle_mm_fault+0x11ae/0x1cd0 mm/memory.c:6202 do_user_addr_fault arch/x86/mm/fault.c:1388 [inline] handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x2b9/0x920 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f2586053ca1 Code: 48 8b 54 24 08 48 85 d2 74 17 8b 44 24 18 0f c8 89 c0 48 89 44 24 18 48 83 fa 01 0f 85 b3 01 00 00 48 8b 44 24 10 8b 54 24 18 <89> 10 e9 15 fd ff ff 48 8b 44 24 10 8b 10 48 8b 44 24 08 48 85 c0 RSP: 002b:00007ffff8e20610 EFLAGS: 00010246 RAX: 0000400000000584 RBX: 0000000000000004 RCX: 0000000000000000 RDX: 000000000000e7b7 RSI: 0000000000000000 RDI: 00005555922033c8 RBP: 00007ffff8e20718 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000002 R12: 00007f25863a5fac R13: 00007f25863a5fa0 R14: fffffffffffffffe R15: 00007ffff8e20760