Hello,
syzbot found the following issue on:
HEAD commit: f4bc5bbb5fef Merge tag 'nfsd-5.17-2' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10fc74c2700000 kernel config: https://syzkaller.appspot.com/x/.config?x=266de9da75c71a45 dashboard link: https://syzkaller.appspot.com/bug?extid=7dcd254b8987a29f6450 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10c73c74700000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1440451c700000
Bisection is inconclusive: the issue happens on the oldest tested release.
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10a40d84700000 final oops: https://syzkaller.appspot.com/x/report.txt?x=12a40d84700000 console output: https://syzkaller.appspot.com/x/log.txt?x=14a40d84700000
IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+7dcd254b8987a29f6450@syzkaller.appspotmail.com
================================ WARNING: inconsistent lock state 5.17.0-rc3-syzkaller-00043-gf4bc5bbb5fef #0 Not tainted -------------------------------- inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage. syz-executor198/3596 [HC1[1]:SC0[0]:HE0:SE1] takes: ffffffff8c7096d8 (sync_timeline_list_lock){?.+.}-{2:2}, at: sync_timeline_debug_remove+0x25/0x190 drivers/dma-buf/sync_debug.c:31 {HARDIRQ-ON-W} state was registered at: __trace_hardirqs_on_caller kernel/locking/lockdep.c:4224 [inline] lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4292 [inline] lockdep_hardirqs_on_prepare+0x135/0x400 kernel/locking/lockdep.c:4244 trace_hardirqs_on+0x5b/0x1c0 kernel/trace/trace_preemptirq.c:49 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] _raw_spin_unlock_irq+0x1f/0x40 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:399 [inline] sync_print_obj drivers/dma-buf/sync_debug.c:118 [inline] sync_info_debugfs_show+0xeb/0x200 drivers/dma-buf/sync_debug.c:153 seq_read_iter+0x4f5/0x1280 fs/seq_file.c:230 seq_read+0x3e8/0x5c0 fs/seq_file.c:162 vfs_read+0x1b5/0x600 fs/read_write.c:479 ksys_read+0x12d/0x250 fs/read_write.c:619 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae irq event stamp: 5708 hardirqs last enabled at (5707): [<ffffffff894db1ef>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:159 [inline] hardirqs last enabled at (5707): [<ffffffff894db1ef>] _raw_spin_unlock_irq+0x1f/0x40 kernel/locking/spinlock.c:202 hardirqs last disabled at (5708): [<ffffffff894a992b>] sysvec_irq_work+0xb/0xc0 arch/x86/kernel/irq_work.c:17 softirqs last enabled at (5570): [<ffffffff84da6fd6>] spin_unlock_bh include/linux/spinlock.h:394 [inline] softirqs last enabled at (5570): [<ffffffff84da6fd6>] __tun_set_ebpf+0xf6/0x1c0 drivers/net/tun.c:2245 softirqs last disabled at (5568): [<ffffffff84da6f83>] spin_lock_bh include/linux/spinlock.h:354 [inline] softirqs last disabled at (5568): [<ffffffff84da6f83>] __tun_set_ebpf+0xa3/0x1c0 drivers/net/tun.c:2241
other info that might help us debug this: Possible unsafe locking scenario:
CPU0 ---- lock(sync_timeline_list_lock); <Interrupt> lock(sync_timeline_list_lock);
*** DEADLOCK ***
no locks held by syz-executor198/3596.
stack backtrace: CPU: 0 PID: 3596 Comm: syz-executor198 Not tainted 5.17.0-rc3-syzkaller-00043-gf4bc5bbb5fef #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:203 [inline] valid_state kernel/locking/lockdep.c:3945 [inline] mark_lock_irq kernel/locking/lockdep.c:4148 [inline] mark_lock.cold+0x61/0x8e kernel/locking/lockdep.c:4605 mark_usage kernel/locking/lockdep.c:4497 [inline] __lock_acquire+0x1499/0x5470 kernel/locking/lockdep.c:4981 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 sync_timeline_debug_remove+0x25/0x190 drivers/dma-buf/sync_debug.c:31 sync_timeline_free drivers/dma-buf/sw_sync.c:104 [inline] kref_put include/linux/kref.h:65 [inline] sync_timeline_put drivers/dma-buf/sw_sync.c:116 [inline] timeline_fence_release+0x263/0x340 drivers/dma-buf/sw_sync.c:144 dma_fence_release+0x2ee/0x590 drivers/dma-buf/dma-fence.c:549 kref_put include/linux/kref.h:65 [inline] dma_fence_put include/linux/dma-fence.h:276 [inline] dma_fence_array_release+0x1e4/0x2b0 drivers/dma-buf/dma-fence-array.c:120 dma_fence_release+0x2ee/0x590 drivers/dma-buf/dma-fence.c:549 kref_put include/linux/kref.h:65 [inline] dma_fence_put include/linux/dma-fence.h:276 [inline] irq_dma_fence_array_work+0xa5/0xd0 drivers/dma-buf/dma-fence-array.c:52 irq_work_single+0x120/0x270 kernel/irq_work.c:211 irq_work_run_list+0x91/0xc0 kernel/irq_work.c:242 irq_work_run+0x54/0xd0 kernel/irq_work.c:251 __sysvec_irq_work+0x95/0x3d0 arch/x86/kernel/irq_work.c:22 sysvec_irq_work+0x8e/0xc0 arch/x86/kernel/irq_work.c:17 </IRQ> <TASK> asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:664 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 4e a1 0f f8 48 89 ef e8 06 17 10 f8 e8 b1 0b 31 f8 fb bf 01 00 00 00 <e8> 46 ca 02 f8 65 8b 05 bf bd b4 76 85 c0 74 02 5d c3 e8 2b 93 b2 RSP: 0018:ffffc90001f5fe18 EFLAGS: 00000206 RAX: 000000000000164b RBX: 00000000ffffffff RCX: 1ffffffff1b27381 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffff8880153ff050 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817ebdd8 R11: 0000000000000000 R12: ffff8880153ff000 R13: dffffc0000000000 R14: ffff8880153ff000 R15: ffff8880153ff050 spin_unlock_irq include/linux/spinlock.h:399 [inline] sw_sync_debugfs_release+0x160/0x240 drivers/dma-buf/sw_sync.c:321 __fput+0x286/0x9f0 fs/file_table.c:313 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fbe1817b7e9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbe17901208 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fbe181fd4f8 RCX: 00007fbe1817b7e9 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000003 RBP: 00007fbe181fd4f0 R08: 00007fbe17901700 R09: 0000000000000000 R10: 00007fbe17901700 R11: 0000000000000246 R12: 00007fbe181fd4fc R1 ---------------- Code disassembly (best guess): 0: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 5: 55 push %rbp 6: 48 8b 74 24 08 mov 0x8(%rsp),%rsi b: 48 89 fd mov %rdi,%rbp e: 48 83 c7 18 add $0x18,%rdi 12: e8 4e a1 0f f8 callq 0xf80fa165 17: 48 89 ef mov %rbp,%rdi 1a: e8 06 17 10 f8 callq 0xf8101725 1f: e8 b1 0b 31 f8 callq 0xf8310bd5 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 46 ca 02 f8 callq 0xf802ca75 <-- trapping instruction 2f: 65 8b 05 bf bd b4 76 mov %gs:0x76b4bdbf(%rip),%eax # 0x76b4bdf5 36: 85 c0 test %eax,%eax 38: 74 02 je 0x3c 3a: 5d pop %rbp 3b: c3 retq 3c: e8 .byte 0xe8 3d: 2b .byte 0x2b 3e: 93 xchg %eax,%ebx 3f: b2 .byte 0xb2
--- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches