WARNING: possible circular locking dependency detected 6.0.0-rc7-next-20220930 #1 Not tainted ------------------------------------------------------ syz-executor.3/4040 is trying to acquire lock: ffffffff853faab8 ((console_sem).lock){....}-{2:2}, at: down_trylock+0xe/0x70 but task is already holding lock: ffff8880092eac20 (&ctx->lock){....}-{2:2}, at: __perf_event_task_sched_out+0x53b/0x18d0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ctx->lock){....}-{2:2}: _raw_spin_lock+0x2a/0x40 __perf_event_task_sched_out+0x53b/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x30/0x40 raw_spin_rq_lock_nested+0x1e/0x30 task_fork_fair+0x63/0x4d0 sched_cgroup_fork+0x3d0/0x540 copy_process+0x4183/0x6e20 kernel_clone+0xe7/0x890 user_mode_thread+0xad/0xf0 rest_init+0x24/0x250 arch_call_rest_init+0xf/0x14 start_kernel+0x4c6/0x4eb secondary_startup_64_no_verify+0xe0/0xeb -> #1 (&p->pi_lock){-.-.}-{2:2}: _raw_spin_lock_irqsave+0x39/0x60 try_to_wake_up+0xab/0x1930 up+0x75/0xb0 __up_console_sem+0x6e/0x80 console_unlock+0x46a/0x590 vt_ioctl+0x2822/0x2ca0 tty_ioctl+0x785/0x16b0 __x64_sys_ioctl+0x19a/0x210 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 ((console_sem).lock){....}-{2:2}: __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 _raw_spin_lock_irqsave+0x39/0x60 down_trylock+0xe/0x70 __down_trylock_console_sem+0x3b/0xd0 vprintk_emit+0x16b/0x560 vprintk+0x84/0xa0 _printk+0xba/0xf1 report_bug.cold+0x72/0xab handle_bug+0x3c/0x70 exc_invalid_op+0x14/0x50 asm_exc_invalid_op+0x16/0x20 group_sched_out.part.0+0x2c7/0x460 ctx_sched_out+0x8f1/0xc10 __perf_event_task_sched_out+0x6d0/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: (console_sem).lock --> &rq->__lock --> &ctx->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ctx->lock); lock(&rq->__lock); lock(&ctx->lock); lock((console_sem).lock); *** DEADLOCK *** 2 locks held by syz-executor.3/4040: #0: ffff88806ce37e98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x1cf/0x2470 #1: ffff8880092eac20 (&ctx->lock){....}-{2:2}, at: __perf_event_task_sched_out+0x53b/0x18d0 stack backtrace: CPU: 0 PID: 4040 Comm: syz-executor.3 Not tainted 6.0.0-rc7-next-20220930 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x8b/0xb3 check_noncircular+0x263/0x2e0 __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 _raw_spin_lock_irqsave+0x39/0x60 down_trylock+0xe/0x70 __down_trylock_console_sem+0x3b/0xd0 vprintk_emit+0x16b/0x560 vprintk+0x84/0xa0 _printk+0xba/0xf1 report_bug.cold+0x72/0xab handle_bug+0x3c/0x70 exc_invalid_op+0x14/0x50 asm_exc_invalid_op+0x16/0x20 RIP: 0010:group_sched_out.part.0+0x2c7/0x460 Code: 5e 41 5f e9 8b ae ef ff e8 86 ae ef ff 65 8b 1d 0b 18 ac 7e 31 ff 89 de e8 26 ab ef ff 85 db 0f 84 8a 00 00 00 e8 69 ae ef ff <0f> 0b e9 a5 fe ff ff e8 5d ae ef ff 48 8d 7d 10 48 b8 00 00 00 00 RSP: 0018:ffff8880400ffc48 EFLAGS: 00010006 RAX: 0000000040000002 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff8880400f0000 RSI: ffffffff81565dc7 RDI: 0000000000000005 RBP: ffff888008660000 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880092eac00 R13: ffff88806ce3d2c0 R14: ffffffff8547c960 R15: 0000000000000002 ctx_sched_out+0x8f1/0xc10 __perf_event_task_sched_out+0x6d0/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f084891ab19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0845e90218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f0848a2df68 RCX: 00007f084891ab19 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f0848a2df6c RBP: 00007f0848a2df60 R08: 000000000000000e R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 00007f0848a2df6c R13: 00007ffce8337f6f R14: 00007f0845e90300 R15: 0000000000022000 WARNING: CPU: 0 PID: 4040 at kernel/events/core.c:2309 group_sched_out.part.0+0x2c7/0x460 Modules linked in: CPU: 0 PID: 4040 Comm: syz-executor.3 Not tainted 6.0.0-rc7-next-20220930 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:group_sched_out.part.0+0x2c7/0x460 Code: 5e 41 5f e9 8b ae ef ff e8 86 ae ef ff 65 8b 1d 0b 18 ac 7e 31 ff 89 de e8 26 ab ef ff 85 db 0f 84 8a 00 00 00 e8 69 ae ef ff <0f> 0b e9 a5 fe ff ff e8 5d ae ef ff 48 8d 7d 10 48 b8 00 00 00 00 RSP: 0018:ffff8880400ffc48 EFLAGS: 00010006 RAX: 0000000040000002 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff8880400f0000 RSI: ffffffff81565dc7 RDI: 0000000000000005 RBP: ffff888008660000 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880092eac00 R13: ffff88806ce3d2c0 R14: ffffffff8547c960 R15: 0000000000000002 FS: 00007f0845e90700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fca9aaac3a4 CR3: 000000003b8aa000 CR4: 0000000000350ef0 Call Trace: ctx_sched_out+0x8f1/0xc10 __perf_event_task_sched_out+0x6d0/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f084891ab19 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0845e90218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f0848a2df68 RCX: 00007f084891ab19 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f0848a2df6c RBP: 00007f0848a2df60 R08: 000000000000000e R09: 0000000000000000 R10: 0000000000000004 R11: 0000000000000246 R12: 00007f0848a2df6c R13: 00007ffce8337f6f R14: 00007f0845e90300 R15: 0000000000022000 irq event stamp: 1520 hardirqs last enabled at (1519): [] exit_to_user_mode_prepare+0x109/0x1a0 hardirqs last disabled at (1520): [] __schedule+0x1225/0x2470 softirqs last enabled at (1408): [] __irq_exit_rcu+0x11b/0x180 softirqs last disabled at (1399): [] __irq_exit_rcu+0x11b/0x180 ---[ end trace 0000000000000000 ]--- netlink: 'syz-executor.3': attribute type 1 has an invalid length. netlink: 'syz-executor.3': attribute type 1 has an invalid length. device syz_tun entered promiscuous mode device syz_tun left promiscuous mode device syz_tun entered promiscuous mode device syz_tun left promiscuous mode device syz_tun entered promiscuous mode device syz_tun left promiscuous mode device syz_tun entered promiscuous mode device syz_tun left promiscuous mode hrtimer: interrupt took 18565 ns device syz_tun entered promiscuous mode device syz_tun left promiscuous mode loop2: detected capacity change from 0 to 320 ISO 9660 Extensions: Microsoft Joliet Level 3 ISO 9660 Extensions: RRIP_1991A loop3: detected capacity change from 0 to 5392 loop7: detected capacity change from 0 to 40 loop7: detected capacity change from 0 to 40 Process accounting resumed Process accounting resumed Process accounting resumed loop7: detected capacity change from 0 to 40 loop6: detected capacity change from 0 to 40 Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed loop6: detected capacity change from 0 to 40 loop7: detected capacity change from 0 to 40 Process accounting resumed Process accounting resumed Process accounting resumed loop6: detected capacity change from 0 to 40 Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed program syz-executor.0 is using a deprecated SCSI ioctl, please convert it to SG_IO Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed netlink: 1 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor.5'. program syz-executor.0 is using a deprecated SCSI ioctl, please convert it to SG_IO netlink: 1 bytes leftover after parsing attributes in process `syz-executor.5'. program syz-executor.0 is using a deprecated SCSI ioctl, please convert it to SG_IO Process accounting resumed program syz-executor.0 is using a deprecated SCSI ioctl, please convert it to SG_IO netlink: 1 bytes leftover after parsing attributes in process `syz-executor.5'. netlink: 1 bytes leftover after parsing attributes in process `syz-executor.5'. loop2: detected capacity change from 0 to 4096 EXT4-fs (loop2): mounted filesystem without journal. Quota mode: writeback. EXT4-fs (loop2): unmounting filesystem. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.6'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.6'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.1'. netlink: 28 bytes leftover after parsing attributes in process `syz-executor.6'. tmpfs: Bad value for 'mpol' tmpfs: Bad value for 'mpol' loop3: detected capacity change from 0 to 264192 FAT-fs (loop3): Unrecognized mount option "fsname=&*:[\" or missing value loop3: detected capacity change from 0 to 264192 FAT-fs (loop3): Unrecognized mount option "fsname=&*:[\" or missing value loop6: detected capacity change from 0 to 264192 loop3: detected capacity change from 0 to 264192 FAT-fs (loop3): Unrecognized mount option "fsname=&*:[\" or missing value loop6: detected capacity change from 0 to 264192