Call Trace: ====================================================== WARNING: possible circular locking dependency detected 5.17.0-rc1-next-20220127 #1 Not tainted ------------------------------------------------------ syz-executor.7/10039 is trying to acquire lock: ffffffff851f5c98 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0xe/0x60 kernel/locking/semaphore.c:138 but task is already holding lock: ffff88801acbf020 (&ctx->lock){-...}-{2:2}, at: __perf_install_in_context+0x12d/0x310 kernel/events/core.c:2818 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ctx->lock){-...}-{2:2}: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 perf_event_context_sched_out kernel/events/core.c:3532 [inline] __perf_event_task_sched_out+0x519/0x1950 kernel/events/core.c:3640 perf_event_task_sched_out include/linux/perf_event.h:1236 [inline] prepare_task_switch kernel/sched/core.c:4796 [inline] context_switch kernel/sched/core.c:4938 [inline] __schedule+0xead/0x2190 kernel/sched/core.c:6295 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6461 __cond_resched+0x13/0x20 kernel/sched/core.c:8174 might_resched include/linux/kernel.h:110 [inline] __mutex_lock_common kernel/locking/mutex.c:577 [inline] __mutex_lock+0xa3/0x1480 kernel/locking/mutex.c:733 __do_sys_perf_event_open+0x1d13/0x3040 kernel/events/core.c:12491 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x30/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x1e/0x30 kernel/sched/core.c:489 raw_spin_rq_lock kernel/sched/sched.h:1318 [inline] rq_lock kernel/sched/sched.h:1616 [inline] task_fork_fair+0x63/0x4d0 kernel/sched/fair.c:11182 sched_post_fork+0x343/0x490 kernel/sched/core.c:4462 copy_process+0x5313/0x6cb0 kernel/fork.c:2379 kernel_clone+0xe7/0xa60 kernel/fork.c:2555 kernel_thread+0xb5/0xf0 kernel/fork.c:2607 rest_init+0x24/0x3d0 init/main.c:692 start_kernel+0x484/0x4a5 init/main.c:1141 secondary_startup_64_no_verify+0xd5/0xdb -> #1 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 try_to_wake_up+0xac/0x14c0 kernel/sched/core.c:4017 up+0x75/0xb0 kernel/locking/semaphore.c:190 __up_console_sem+0x6e/0x80 kernel/printk/printk.c:255 console_unlock+0x53e/0xae0 kernel/printk/printk.c:2730 do_con_write+0xc01/0x1d40 drivers/tty/vt/vt.c:2965 con_write+0x21/0x40 drivers/tty/vt/vt.c:3295 process_output_block drivers/tty/n_tty.c:581 [inline] n_tty_write+0x416/0xfe0 drivers/tty/n_tty.c:2250 do_tty_write drivers/tty/tty_io.c:1024 [inline] file_tty_write.constprop.0+0x529/0x910 drivers/tty/tty_io.c:1095 call_write_iter include/linux/fs.h:2074 [inline] new_sync_write+0x437/0x660 fs/read_write.c:504 vfs_write+0x7d1/0xae0 fs/read_write.c:591 ksys_write+0x12d/0x250 fs/read_write.c:644 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae -> #0 ((console_sem).lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3063 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain kernel/locking/lockdep.c:3801 [inline] __lock_acquire+0x2a14/0x5b70 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1a2/0x4d0 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 down_trylock+0xe/0x60 kernel/locking/semaphore.c:138 __down_trylock_console_sem+0x3b/0xd0 kernel/printk/printk.c:238 console_trylock kernel/printk/printk.c:2545 [inline] console_trylock_spinning kernel/printk/printk.c:1846 [inline] vprintk_emit+0x146/0x450 kernel/printk/printk.c:2247 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2269 show_trace_log_lvl+0x57/0x2bb arch/x86/kernel/dumpstack.c:195 ex_handler_msr+0x311/0x3a0 arch/x86/mm/extable.c:101 fixup_exception+0x1c7/0xc90 arch/x86/mm/extable.c:200 __exc_general_protection arch/x86/kernel/traps.c:601 [inline] exc_general_protection+0xed/0x2f0 arch/x86/kernel/traps.c:562 asm_exc_general_protection+0x1e/0x30 arch/x86/include/asm/idtentry.h:562 wrmsrl arch/x86/include/asm/msr.h:271 [inline] __x86_pmu_enable_event arch/x86/events/perf_event.h:1126 [inline] x86_pmu_enable_all+0x2f7/0x3c0 arch/x86/events/core.c:743 x86_pmu_enable+0x580/0xd90 arch/x86/events/core.c:1350 perf_pmu_enable kernel/events/core.c:1237 [inline] perf_pmu_enable kernel/events/core.c:1233 [inline] ctx_resched+0x2b0/0x390 kernel/events/core.c:2788 __perf_install_in_context+0x285/0x310 kernel/events/core.c:2855 remote_function kernel/events/core.c:91 [inline] remote_function+0x125/0x1b0 kernel/events/core.c:71 generic_exec_single+0x203/0x300 kernel/smp.c:518 smp_call_function_single+0x189/0x460 kernel/smp.c:755 task_function_call+0xe5/0x170 kernel/events/core.c:119 perf_install_in_context+0x2cb/0x550 kernel/events/core.c:2956 __do_sys_perf_event_open+0x1bf0/0x3040 kernel/events/core.c:12479 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae 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 *** 4 locks held by syz-executor.7/10039: #0: ffff88801e3985e0 (&sig->exec_update_lock){++++}-{3:3}, at: __do_sys_perf_event_open+0x1023/0x3040 kernel/events/core.c:12319 #1: ffff88801acbf0b0 (&ctx->mutex){+.+.}-{3:3}, at: __do_sys_perf_event_open+0x17cd/0x3040 kernel/events/core.c:12373 #2: ffff88806ce3ee20 (&cpuctx_lock){-.-.}-{2:2}, at: __perf_install_in_context+0xf4/0x310 kernel/events/core.c:2816 #3: ffff88801acbf020 (&ctx->lock){-...}-{2:2}, at: __perf_install_in_context+0x12d/0x310 kernel/events/core.c:2818 stack backtrace: CPU: 0 PID: 10039 Comm: syz-executor.7 Not tainted 5.17.0-rc1-next-20220127 #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 lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2143 check_prev_add kernel/locking/lockdep.c:3063 [inline] check_prevs_add kernel/locking/lockdep.c:3186 [inline] validate_chain kernel/locking/lockdep.c:3801 [inline] __lock_acquire+0x2a14/0x5b70 kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5639 [inline] lock_acquire+0x1a2/0x4d0 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 down_trylock+0xe/0x60 kernel/locking/semaphore.c:138 __down_trylock_console_sem+0x3b/0xd0 kernel/printk/printk.c:238 console_trylock kernel/printk/printk.c:2545 [inline] console_trylock_spinning kernel/printk/printk.c:1846 [inline] vprintk_emit+0x146/0x450 kernel/printk/printk.c:2247 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2269 show_trace_log_lvl+0x57/0x2bb arch/x86/kernel/dumpstack.c:195 ex_handler_msr+0x311/0x3a0 arch/x86/mm/extable.c:101 fixup_exception+0x1c7/0xc90 arch/x86/mm/extable.c:200 __exc_general_protection arch/x86/kernel/traps.c:601 [inline] exc_general_protection+0xed/0x2f0 arch/x86/kernel/traps.c:562 asm_exc_general_protection+0x1e/0x30 arch/x86/include/asm/idtentry.h:562 RIP: 0010:__wrmsr arch/x86/include/asm/msr.h:103 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:154 [inline] RIP: 0010:wrmsrl arch/x86/include/asm/msr.h:271 [inline] RIP: 0010:__x86_pmu_enable_event arch/x86/events/perf_event.h:1126 [inline] RIP: 0010:x86_pmu_enable_all+0x2f7/0x3c0 arch/x86/events/core.c:743 Code: 00 8b 7c 24 1c 48 8b 44 24 10 0f ae e8 ff d0 89 44 24 10 e8 eb 5f 42 00 4c 89 fa 8b 4c 24 08 4c 89 f8 03 4c 24 10 48 c1 ea 20 <0f> 30 66 90 e8 d0 5f 42 00 e9 cc fd ff ff 48 83 c4 20 5b 5d 41 5c RSP: 0018:ffff88803edff968 EFLAGS: 00010016 RAX: 0000000f004000ff RBX: ffff88801d1fadc0 RCX: 00000000c0010202 RDX: 000000000000000f RSI: ffffffff8100e045 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff81015b2d R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88806ce21c20 R14: ffff88806ce21e20 R15: 0000000f004000ff x86_pmu_enable+0x580/0xd90 arch/x86/events/core.c:1350 perf_pmu_enable kernel/events/core.c:1237 [inline] perf_pmu_enable kernel/events/core.c:1233 [inline] ctx_resched+0x2b0/0x390 kernel/events/core.c:2788 __perf_install_in_context+0x285/0x310 kernel/events/core.c:2855 remote_function kernel/events/core.c:91 [inline] remote_function+0x125/0x1b0 kernel/events/core.c:71 generic_exec_single+0x203/0x300 kernel/smp.c:518 smp_call_function_single+0x189/0x460 kernel/smp.c:755 task_function_call+0xe5/0x170 kernel/events/core.c:119 perf_install_in_context+0x2cb/0x550 kernel/events/core.c:2956 __do_sys_perf_event_open+0x1bf0/0x3040 kernel/events/core.c:12479 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fb0fd5d2b19 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:00007fb0fab48188 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fb0fd6e5f60 RCX: 00007fb0fd5d2b19 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 00000000200038c0 RBP: 00007fb0fd62cf6d R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff706d13ff R14: 00007fb0fab48300 R15: 0000000000022000 x86_pmu_enable+0x580/0xd90 arch/x86/events/core.c:1350 perf_pmu_enable kernel/events/core.c:1237 [inline] perf_pmu_enable kernel/events/core.c:1233 [inline] ctx_resched+0x2b0/0x390 kernel/events/core.c:2788 __perf_install_in_context+0x285/0x310 kernel/events/core.c:2855 remote_function kernel/events/core.c:91 [inline] remote_function+0x125/0x1b0 kernel/events/core.c:71 generic_exec_single+0x203/0x300 kernel/smp.c:518 smp_call_function_single+0x189/0x460 kernel/smp.c:755 task_function_call+0xe5/0x170 kernel/events/core.c:119 perf_install_in_context+0x2cb/0x550 kernel/events/core.c:2956 __do_sys_perf_event_open+0x1bf0/0x3040 kernel/events/core.c:12479 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fb0fd5d2b19 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:00007fb0fab48188 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fb0fd6e5f60 RCX: 00007fb0fd5d2b19 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 00000000200038c0 RBP: 00007fb0fd62cf6d R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff706d13ff R14: 00007fb0fab48300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 00 8b 7c 24 1c 48 add %cl,0x481c247c(%rbx) 6: 8b 44 24 10 mov 0x10(%rsp),%eax a: 0f ae e8 lfence d: ff d0 callq *%rax f: 89 44 24 10 mov %eax,0x10(%rsp) 13: e8 eb 5f 42 00 callq 0x426003 18: 4c 89 fa mov %r15,%rdx 1b: 8b 4c 24 08 mov 0x8(%rsp),%ecx 1f: 4c 89 f8 mov %r15,%rax 22: 03 4c 24 10 add 0x10(%rsp),%ecx 26: 48 c1 ea 20 shr $0x20,%rdx * 2a: 0f 30 wrmsr <-- trapping instruction 2c: 66 90 xchg %ax,%ax 2e: e8 d0 5f 42 00 callq 0x426003 33: e9 cc fd ff ff jmpq 0xfffffe04 38: 48 83 c4 20 add $0x20,%rsp 3c: 5b pop %rbx 3d: 5d pop %rbp 3e: 41 5c pop %r12