======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- syz-executor.2/5597 just changed the state of lock: ffff888029c8a948 (&timer->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff888029c8a948 (&timer->lock){+.+.}-{2:2}, at: class_spinlock_constructor include/linux/spinlock.h:561 [inline] ffff888029c8a948 (&timer->lock){+.+.}-{2:2}, at: snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 but this lock was taken by another, SOFTIRQ-safe lock in the past: (&group->lock#2){..-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&timer->lock); local_irq_disable(); lock(&group->lock#2); lock(&timer->lock); lock(&group->lock#2); *** DEADLOCK *** 2 locks held by syz-executor.2/5597: #0: ffff88807c17ed68 (&tu->ioctl_lock){+.+.}-{3:3}, at: class_mutex_constructor include/linux/mutex.h:169 [inline] #0: ffff88807c17ed68 (&tu->ioctl_lock){+.+.}-{3:3}, at: snd_timer_user_release+0xbc/0x2e0 sound/core/timer.c:1466 #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: class_mutex_constructor include/linux/mutex.h:169 [inline] #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: snd_timer_close sound/core/timer.c:463 [inline] #1: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: snd_timer_user_release+0x12b/0x2e0 sound/core/timer.c:1468 the shortest dependencies between 2nd lock and 1st lock: -> (&group->lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x21/0x50 sound/core/pcm_lib.c:1904 dummy_hrtimer_callback+0x7f/0x180 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1692 [inline] __hrtimer_run_queues+0x595/0xd00 kernel/time/hrtimer.c:1756 hrtimer_run_softirq+0x19a/0x2c0 kernel/time/hrtimer.c:1773 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 lock_acquire+0x25b/0x530 kernel/locking/lockdep.c:5758 rcu_lock_acquire include/linux/rcupdate.h:298 [inline] rcu_read_lock include/linux/rcupdate.h:750 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] class_pcm_stream_lock_irq_constructor include/sound/pcm.h:666 [inline] snd_pcm_hw_params+0x201/0x1ea0 sound/core/pcm_native.c:740 snd_pcm_oss_change_params_locked+0x20d5/0x3e00 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1105 [inline] snd_pcm_oss_get_active_substream+0x201/0x280 sound/core/oss/pcm_oss.c:1122 snd_pcm_oss_get_rate sound/core/oss/pcm_oss.c:1778 [inline] snd_pcm_oss_set_rate+0x248/0x5d0 sound/core/oss/pcm_oss.c:1770 snd_pcm_oss_ioctl+0xe31/0xff0 sound/core/oss/pcm_oss.c:2623 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 } ... key at: [] snd_pcm_group_init.__key+0x0/0x20 ... acquired at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x103/0x3d0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_stop sound/core/pcm_native.c:1520 [inline] snd_pcm_action sound/core/pcm_native.c:1370 [inline] snd_pcm_stop+0x358/0x490 sound/core/pcm_native.c:1543 snd_pcm_drop+0x158/0x250 sound/core/pcm_native.c:2208 snd_pcm_oss_sync+0x202/0xc30 sound/core/oss/pcm_oss.c:1734 snd_pcm_oss_release+0x11e/0x280 sound/core/oss/pcm_oss.c:2575 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close sound/core/timer.c:464 [inline] snd_timer_user_release+0x138/0x2e0 sound/core/timer.c:1468 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 SOFTIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close sound/core/timer.c:464 [inline] snd_timer_user_release+0x138/0x2e0 sound/core/timer.c:1468 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x103/0x3d0 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:622 [inline] snd_pcm_post_stop sound/core/pcm_native.c:1520 [inline] snd_pcm_action sound/core/pcm_native.c:1370 [inline] snd_pcm_stop+0x358/0x490 sound/core/pcm_native.c:1543 snd_pcm_drop+0x158/0x250 sound/core/pcm_native.c:2208 snd_pcm_oss_sync+0x202/0xc30 sound/core/oss/pcm_oss.c:1734 snd_pcm_oss_release+0x11e/0x280 sound/core/oss/pcm_oss.c:2575 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 } ... key at: [] snd_timer_new.__key+0x0/0x20 ... acquired at: mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0x116e/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close sound/core/timer.c:464 [inline] snd_timer_user_release+0x138/0x2e0 sound/core/timer.c:1468 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 stack backtrace: CPU: 0 PID: 5597 Comm: syz-executor.2 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 mark_lock_irq+0x867/0xc20 kernel/locking/lockdep.c:4236 mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0x116e/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close sound/core/timer.c:464 [inline] snd_timer_user_release+0x138/0x2e0 sound/core/timer.c:1468 __fput+0x429/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 RIP: 0023:0xf72d0579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f7571ad0 EFLAGS: 00000206 ORIG_RAX: 0000000000000006 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000005686d400 RDX: 0000000000000000 RSI: 00000000f7427ff4 RDI: 0000000000000000 RBP: 00000000f72cc000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop