loop8: detected capacity change from 0 to 32768 ocfs2: Mounting device (7,8) on (node local, slot 0) with ordered data mode. ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc6-syzkaller #0 Not tainted ------------------------------------------------------ syz.8.983/15129 is trying to acquire lock: ffff88804ef394a0 (&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: ffff888033f70520 (sb_pagefaults#6){.+.+}-{0:0}, at: do_page_mkwrite+0x14a/0x310 mm/memory.c:3378 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (sb_pagefaults#6){.+.+}-{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:1795 [inline] sb_start_pagefault include/linux/fs.h:1960 [inline] ocfs2_page_mkwrite+0x1da/0xc40 fs/ocfs2/mmap.c:122 do_page_mkwrite+0x14a/0x310 mm/memory.c:3378 wp_page_shared mm/memory.c:3779 [inline] do_wp_page+0x268d/0x5800 mm/memory.c:3998 handle_pte_fault mm/memory.c:6085 [inline] __handle_mm_fault+0x1144/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 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 do_sys_poll+0xe52/0x1070 fs/select.c:1020 __do_sys_poll fs/select.c:1074 [inline] __se_sys_poll+0x128/0x320 fs/select.c:1062 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 -> #1 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871 __might_fault+0xcc/0x130 mm/memory.c:6971 _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+0x16d3/0x1990 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:3378 wp_page_shared mm/memory.c:3779 [inline] do_wp_page+0x268d/0x5800 mm/memory.c:3998 handle_pte_fault mm/memory.c:6085 [inline] __handle_mm_fault+0x1144/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 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 do_sys_poll+0xe52/0x1070 fs/select.c:1020 __do_sys_poll fs/select.c:1074 [inline] __se_sys_poll+0x128/0x320 fs/select.c:1062 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 other info that might help us debug this: Chain exists of: &ocfs2_file_ip_alloc_sem_key --> &mm->mmap_lock --> sb_pagefaults#6 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#6); lock(&mm->mmap_lock); lock(sb_pagefaults#6); lock(&ocfs2_file_ip_alloc_sem_key); *** DEADLOCK *** 2 locks held by syz.8.983/15129: #0: ffff88807bf0efe0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:431 [inline] #0: ffff88807bf0efe0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:188 [inline] #0: ffff88807bf0efe0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x300 mm/mmap_lock.c:248 #1: ffff888033f70520 (sb_pagefaults#6){.+.+}-{0:0}, at: do_page_mkwrite+0x14a/0x310 mm/memory.c:3378 stack backtrace: CPU: 1 UID: 0 PID: 15129 Comm: syz.8.983 Not tainted 6.16.0-rc6-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:3378 wp_page_shared mm/memory.c:3779 [inline] do_wp_page+0x268d/0x5800 mm/memory.c:3998 handle_pte_fault mm/memory.c:6085 [inline] __handle_mm_fault+0x1144/0x5620 mm/memory.c:6212 handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6381 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: 0010:do_sys_poll+0xe52/0x1070 fs/select.c:1020 Code: 8b 74 24 18 4c 8d 76 12 45 31 ff 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 2b 42 0f b7 44 fe 12 <66> 89 02 49 89 d4 44 39 fb 74 3b e8 4e 25 88 ff 4c 89 e2 48 83 c2 RSP: 0018:ffffc90003437860 EFLAGS: 00050246 RAX: 0000000000000000 RBX: 000000000000001d RCX: dffffc0000000000 RDX: 0000200000005f06 RSI: ffffc90003437c70 RDI: 0000000000000000 RBP: ffffc90003437e10 R08: ffff8880b873fb83 R09: 1ffff110170e7f70 R10: dffffc0000000000 R11: ffffed10170e7f71 R12: 0000200000006120 R13: 0000000000000000 R14: ffffc90003437c82 R15: 0000000000000000 __do_sys_poll fs/select.c:1074 [inline] __se_sys_poll+0x128/0x320 fs/select.c:1062 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 RIP: 0033:0x7efce6d8e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007efce7c8b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000007 RAX: ffffffffffffffda RBX: 00007efce6fb5fa0 RCX: 00007efce6d8e929 RDX: 0000000000000002 RSI: 0000000000000044 RDI: 0000200000005f00 RBP: 00007efce6e10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007efce6fb5fa0 R15: 00007ffe8b09f488 ---------------- Code disassembly (best guess): 0: 8b 74 24 18 mov 0x18(%rsp),%esi 4: 4c 8d 76 12 lea 0x12(%rsi),%r14 8: 45 31 ff xor %r15d,%r15d b: 4c 89 f0 mov %r14,%rax e: 48 c1 e8 03 shr $0x3,%rax 12: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 19: fc ff df 1c: 0f b6 04 08 movzbl (%rax,%rcx,1),%eax 20: 84 c0 test %al,%al 22: 75 2b jne 0x4f 24: 42 0f b7 44 fe 12 movzwl 0x12(%rsi,%r15,8),%eax * 2a: 66 89 02 mov %ax,(%rdx) <-- trapping instruction 2d: 49 89 d4 mov %rdx,%r12 30: 44 39 fb cmp %r15d,%ebx 33: 74 3b je 0x70 35: e8 4e 25 88 ff call 0xff882588 3a: 4c 89 e2 mov %r12,%rdx 3d: 48 rex.W 3e: 83 .byte 0x83 3f: c2 .byte 0xc2