EEVDF scheduling fail, picking leftmost ====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc6-syzkaller-00182-gce55c22ec8b2 #0 Not tainted ------------------------------------------------------ syz-executor.2/14141 is trying to acquire lock: ffffffff8cb98f78 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139 but task is already holding lock: ffff8880b993c718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558 raw_spin_rq_lock kernel/sched/sched.h:1372 [inline] rq_lock kernel/sched/sched.h:1681 [inline] task_fork_fair+0x70/0x240 kernel/sched/fair.c:12416 sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4816 copy_process+0x45ec/0x73f0 kernel/fork.c:2609 kernel_clone+0xfd/0x920 kernel/fork.c:2909 user_mode_thread+0xb4/0xf0 kernel/fork.c:2987 rest_init+0x27/0x2b0 init/main.c:691 arch_call_rest_init+0x13/0x30 init/main.c:823 start_kernel+0x39f/0x480 init/main.c:1068 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0x166/0x16b -> #1 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:518 [inline] try_to_wake_up+0xb0/0x15b0 kernel/sched/core.c:4230 up+0x79/0xb0 kernel/locking/semaphore.c:191 __up_console_sem kernel/printk/printk.c:346 [inline] __console_unlock kernel/printk/printk.c:2718 [inline] console_unlock+0x1cf/0x260 kernel/printk/printk.c:3037 vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2307 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2332 input_register_device+0xa11/0x1130 drivers/input/input.c:2384 uinput_create_device drivers/input/misc/uinput.c:365 [inline] uinput_ioctl_handler.isra.0+0x1308/0x1d70 drivers/input/misc/uinput.c:904 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 ((console_sem).lock){-...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 down_trylock+0x12/0x70 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:329 console_trylock+0x73/0x130 kernel/printk/printk.c:2671 console_trylock_spinning kernel/printk/printk.c:1927 [inline] vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2306 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2332 pick_eevdf kernel/sched/fair.c:976 [inline] pick_next_entity kernel/sched/fair.c:5278 [inline] pick_next_task_fair+0x1c5/0x1280 kernel/sched/fair.c:8222 __pick_next_task kernel/sched/core.c:6004 [inline] pick_next_task kernel/sched/core.c:6079 [inline] __schedule+0x493/0x5a10 kernel/sched/core.c:6659 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 do_nanosleep+0x218/0x500 kernel/time/hrtimer.c:2047 hrtimer_nanosleep+0x1ae/0x440 kernel/time/hrtimer.c:2100 common_nsleep+0xa1/0xc0 kernel/time/posix-timers.c:1350 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1373 [inline] __x64_sys_clock_nanosleep+0x344/0x490 kernel/time/posix-timers.c:1373 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: (console_sem).lock --> &p->pi_lock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&p->pi_lock); lock(&rq->__lock); lock((console_sem).lock); *** DEADLOCK *** 1 lock held by syz-executor.2/14141: #0: ffff8880b993c718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558 stack backtrace: CPU: 1 PID: 14141 Comm: syz-executor.2 Not tainted 6.6.0-rc6-syzkaller-00182-gce55c22ec8b2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 down_trylock+0x12/0x70 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:329 console_trylock+0x73/0x130 kernel/printk/printk.c:2671 console_trylock_spinning kernel/printk/printk.c:1927 [inline] vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2306 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2332 pick_eevdf kernel/sched/fair.c:976 [inline] pick_next_entity kernel/sched/fair.c:5278 [inline] pick_next_task_fair+0x1c5/0x1280 kernel/sched/fair.c:8222 __pick_next_task kernel/sched/core.c:6004 [inline] pick_next_task kernel/sched/core.c:6079 [inline] __schedule+0x493/0x5a10 kernel/sched/core.c:6659 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 do_nanosleep+0x218/0x500 kernel/time/hrtimer.c:2047 hrtimer_nanosleep+0x1ae/0x440 kernel/time/hrtimer.c:2100 common_nsleep+0xa1/0xc0 kernel/time/posix-timers.c:1350 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1373 [inline] __x64_sys_clock_nanosleep+0x344/0x490 kernel/time/posix-timers.c:1373 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa0cc0a7ef5 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 b9 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f ba ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007fa0cc2bfac0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 00007fa0cc19bf80 RCX: 00007fa0cc0a7ef5 RDX: 00007fa0cc2bfb00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fa0cc19d980 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000089591 R13: ffffffffffffffff R14: 00007fa0cbc00000 R15: 0000000000089250