======================================================== WARNING: possible irq lock inversion dependency detected 5.9.0-syzkaller #0 Not tainted -------------------------------------------------------- syz-executor.2/6879 just changed the state of lock: ffff888214deb908 (&group->lock){..-.}-{2:2}, at: snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 but this lock took another, SOFTIRQ-READ-unsafe lock in the past: (&card->ctl_files_rwlock){.+.+}-{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(&card->ctl_files_rwlock); local_irq_disable(); lock(&group->lock); lock(&card->ctl_files_rwlock); lock(&group->lock); *** DEADLOCK *** 3 locks held by syz-executor.2/6879: #0: ffff888099aac308 (&xt[i].mutex){+.+.}-{3:3}, at: xt_find_table_lock+0x37/0x410 net/netfilter/x_tables.c:1206 #1: ffffffff8a9a9af8 (vmap_area_lock ){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:354 [inline] ){+.+.}-{2:2}, at: remove_vm_area+0x35/0x210 mm/vmalloc.c:2165 #2: ffffc90000da8db0 ((&dpcm->timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline] ffffc90000da8db0 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0x57/0x160 kernel/time/timer.c:1405 the shortest dependencies between 2nd lock and 1st lock: -> (&card->ctl_files_rwlock){.+.+}-{2:2} { HARDIRQ-ON-R at: lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 __snd_ctl_add_replace+0x582/0x8a0 sound/core/control.c:382 snd_ctl_add_replace sound/core/control.c:399 [inline] snd_ctl_add+0x6e/0x110 sound/core/control.c:426 snd_card_dummy_new_mixer sound/drivers/dummy.c:885 [inline] snd_dummy_probe+0x12bb/0x1ff0 sound/drivers/dummy.c:1080 platform_drv_probe+0xcd/0x150 drivers/base/platform.c:761 really_probe+0x74b/0x1100 drivers/base/dd.c:558 driver_probe_device+0x106/0x1a0 drivers/base/dd.c:738 bus_for_each_drv+0x108/0x170 drivers/base/bus.c:431 __device_attach+0x262/0x3f0 drivers/base/dd.c:912 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:491 device_add+0x15e6/0x1960 drivers/base/core.c:2936 platform_device_add+0x4ad/0x6e0 drivers/base/platform.c:611 platform_device_register_full+0x445/0x530 drivers/base/platform.c:734 platform_device_register_resndata include/linux/platform_device.h:131 [inline] platform_device_register_simple include/linux/platform_device.h:160 [inline] alsa_card_dummy_init+0x1b3/0x39c sound/drivers/dummy.c:1168 do_one_initcall+0x14b/0x350 init/main.c:1205 do_initcall_level+0x1fb/0x2c0 init/main.c:1278 do_initcalls+0x4b/0x8c init/main.c:1294 kernel_init_freeable+0x356/0x474 init/main.c:1514 kernel_init+0xd/0x290 init/main.c:1403 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 SOFTIRQ-ON-R at: lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 __snd_ctl_add_replace+0x582/0x8a0 sound/core/control.c:382 snd_ctl_add_replace sound/core/control.c:399 [inline] snd_ctl_add+0x6e/0x110 sound/core/control.c:426 snd_card_dummy_new_mixer sound/drivers/dummy.c:885 [inline] snd_dummy_probe+0x12bb/0x1ff0 sound/drivers/dummy.c:1080 platform_drv_probe+0xcd/0x150 drivers/base/platform.c:761 really_probe+0x74b/0x1100 drivers/base/dd.c:558 driver_probe_device+0x106/0x1a0 drivers/base/dd.c:738 bus_for_each_drv+0x108/0x170 drivers/base/bus.c:431 __device_attach+0x262/0x3f0 drivers/base/dd.c:912 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:491 device_add+0x15e6/0x1960 drivers/base/core.c:2936 platform_device_add+0x4ad/0x6e0 drivers/base/platform.c:611 platform_device_register_full+0x445/0x530 drivers/base/platform.c:734 platform_device_register_resndata include/linux/platform_device.h:131 [inline] platform_device_register_simple include/linux/platform_device.h:160 [inline] alsa_card_dummy_init+0x1b3/0x39c sound/drivers/dummy.c:1168 do_one_initcall+0x14b/0x350 init/main.c:1205 do_initcall_level+0x1fb/0x2c0 init/main.c:1278 do_initcalls+0x4b/0x8c init/main.c:1294 kernel_init_freeable+0x356/0x474 init/main.c:1514 kernel_init+0xd/0x290 init/main.c:1403 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 INITIAL READ USE at: lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 __snd_ctl_add_replace+0x582/0x8a0 sound/core/control.c:382 snd_ctl_add_replace sound/core/control.c:399 [inline] snd_ctl_add+0x6e/0x110 sound/core/control.c:426 snd_card_dummy_new_mixer sound/drivers/dummy.c:885 [inline] snd_dummy_probe+0x12bb/0x1ff0 sound/drivers/dummy.c:1080 platform_drv_probe+0xcd/0x150 drivers/base/platform.c:761 really_probe+0x74b/0x1100 drivers/base/dd.c:558 driver_probe_device+0x106/0x1a0 drivers/base/dd.c:738 bus_for_each_drv+0x108/0x170 drivers/base/bus.c:431 __device_attach+0x262/0x3f0 drivers/base/dd.c:912 bus_probe_device+0xb8/0x1f0 drivers/base/bus.c:491 device_add+0x15e6/0x1960 drivers/base/core.c:2936 platform_device_add+0x4ad/0x6e0 drivers/base/platform.c:611 platform_device_register_full+0x445/0x530 drivers/base/platform.c:734 platform_device_register_resndata include/linux/platform_device.h:131 [inline] platform_device_register_simple include/linux/platform_device.h:160 [inline] alsa_card_dummy_init+0x1b3/0x39c sound/drivers/dummy.c:1168 do_one_initcall+0x14b/0x350 init/main.c:1205 do_initcall_level+0x1fb/0x2c0 init/main.c:1278 do_initcalls+0x4b/0x8c init/main.c:1294 kernel_init_freeable+0x356/0x474 init/main.c:1514 kernel_init+0xd/0x290 init/main.c:1403 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 } ... key at: [] snd_card_new.__key.3+0x0/0x40 ... acquired at: lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_read_lock include/linux/rwlock_api_smp.h:149 [inline] _raw_read_lock+0x32/0x40 kernel/locking/spinlock.c:223 snd_ctl_notify+0x86/0x550 sound/core/control.c:153 loopback_check_format sound/drivers/aloop.c:358 [inline] loopback_trigger+0xddb/0x17f0 sound/drivers/aloop.c:387 snd_pcm_do_start sound/core/pcm_native.c:1350 [inline] snd_pcm_action_single sound/core/pcm_native.c:1207 [inline] snd_pcm_action sound/core/pcm_native.c:1290 [inline] snd_pcm_start+0x475/0x6d0 sound/core/pcm_native.c:1391 __snd_pcm_lib_xfer+0xf3d/0x12f0 sound/core/pcm_lib.c:2247 snd_pcm_oss_write3+0x209/0x330 sound/core/oss/pcm_oss.c:1221 snd_pcm_plug_write_transfer+0x28b/0x490 sound/core/oss/pcm_plugin.c:624 snd_pcm_oss_write2 sound/core/oss/pcm_oss.c:1353 [inline] snd_pcm_oss_sync1+0x29d/0x770 sound/core/oss/pcm_oss.c:1594 snd_pcm_oss_sync+0x5c2/0x940 sound/core/oss/pcm_oss.c:1659 snd_pcm_oss_release+0x119/0x270 sound/core/oss/pcm_oss.c:2546 __fput+0x34f/0x7b0 fs/file_table.c:281 task_work_run+0x137/0x1c0 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:165 [inline] exit_to_user_mode_prepare+0x11d/0x1e0 kernel/entry/common.c:192 syscall_exit_to_user_mode+0x82/0x1c0 kernel/entry/common.c:267 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> (&group->lock){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xaa/0xd0 kernel/locking/spinlock.c:159 snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 call_timer_fn+0x91/0x160 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers+0x770/0x9a0 kernel/time/timer.c:1757 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1770 __do_softirq+0x388/0x748 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9a/0xe0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu+0x200/0x230 kernel/softirq.c:423 irq_exit_rcu+0x5/0x20 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0xe0/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 arch_local_irq_restore arch/x86/include/asm/paravirt.h:653 [inline] lock_acquire+0x1c0/0x6e0 kernel/locking/lockdep.c:5445 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] remove_vm_area+0x35/0x210 mm/vmalloc.c:2165 vm_remove_mappings mm/vmalloc.c:2201 [inline] __vunmap+0x2ed/0xa20 mm/vmalloc.c:2263 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:867 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1023 [inline] do_ipt_get_ctl+0x150d/0x1a10 net/ipv4/netfilter/ip_tables.c:1660 nf_getsockopt+0x2ab/0x2d0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x1f69/0x2870 net/ipv4/ip_sockglue.c:1778 tcp_getsockopt+0x1e2/0x2960 net/ipv4/tcp.c:3877 __sys_getsockopt+0x290/0x4c0 net/socket.c:2173 __do_sys_getsockopt net/socket.c:2188 [inline] __se_sys_getsockopt net/socket.c:2185 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2185 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 INITIAL USE at: lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:128 [inline] _raw_spin_lock_irq+0xa6/0xc0 kernel/locking/spinlock.c:167 spin_lock_irq include/linux/spinlock.h:379 [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] snd_pcm_hw_params+0xca/0x16a0 sound/core/pcm_native.c:672 snd_pcm_oss_change_params_locked+0x2102/0x3e00 sound/core/oss/pcm_oss.c:941 snd_pcm_oss_make_ready_locked sound/core/oss/pcm_oss.c:1166 [inline] snd_pcm_oss_write1 sound/core/oss/pcm_oss.c:1384 [inline] snd_pcm_oss_write+0x269/0xd70 sound/core/oss/pcm_oss.c:2765 vfs_write+0x2dd/0xd10 fs/read_write.c:584 ksys_write+0x11b/0x220 fs/read_write.c:639 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 } ... key at: [] snd_pcm_group_init.__key+0x0/0x40 ... acquired at: mark_usage kernel/locking/lockdep.c:4305 [inline] __lock_acquire+0x9ee/0x6a40 kernel/locking/lockdep.c:4791 lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xaa/0xd0 kernel/locking/spinlock.c:159 snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 call_timer_fn+0x91/0x160 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers+0x770/0x9a0 kernel/time/timer.c:1757 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1770 __do_softirq+0x388/0x748 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9a/0xe0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu+0x200/0x230 kernel/softirq.c:423 irq_exit_rcu+0x5/0x20 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0xe0/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 arch_local_irq_restore arch/x86/include/asm/paravirt.h:653 [inline] lock_acquire+0x1c0/0x6e0 kernel/locking/lockdep.c:5445 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] remove_vm_area+0x35/0x210 mm/vmalloc.c:2165 vm_remove_mappings mm/vmalloc.c:2201 [inline] __vunmap+0x2ed/0xa20 mm/vmalloc.c:2263 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:867 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1023 [inline] do_ipt_get_ctl+0x150d/0x1a10 net/ipv4/netfilter/ip_tables.c:1660 nf_getsockopt+0x2ab/0x2d0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x1f69/0x2870 net/ipv4/ip_sockglue.c:1778 tcp_getsockopt+0x1e2/0x2960 net/ipv4/tcp.c:3877 __sys_getsockopt+0x290/0x4c0 net/socket.c:2173 __do_sys_getsockopt net/socket.c:2188 [inline] __se_sys_getsockopt net/socket.c:2185 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2185 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 stack backtrace: CPU: 1 PID: 6879 Comm: syz-executor.2 Not tainted 5.9.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d6/0x29e lib/dump_stack.c:118 print_irq_inversion_bug+0xa5d/0xde0 kernel/locking/lockdep.c:3817 check_usage_forwards kernel/locking/lockdep.c:2470 [inline] mark_lock_irq kernel/locking/lockdep.c:3980 [inline] mark_lock+0x111b/0x1e20 kernel/locking/lockdep.c:4408 mark_usage kernel/locking/lockdep.c:4305 [inline] __lock_acquire+0x9ee/0x6a40 kernel/locking/lockdep.c:4791 lock_acquire+0x160/0x6e0 kernel/locking/lockdep.c:5442 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xaa/0xd0 kernel/locking/spinlock.c:159 snd_pcm_period_elapsed+0x2c/0x210 sound/core/pcm_lib.c:1799 call_timer_fn+0x91/0x160 kernel/time/timer.c:1415 expire_timers kernel/time/timer.c:1460 [inline] __run_timers+0x770/0x9a0 kernel/time/timer.c:1757 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1770 __do_softirq+0x388/0x748 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x9a/0xe0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu+0x200/0x230 kernel/softirq.c:423 irq_exit_rcu+0x5/0x20 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0xe0/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:653 [inline] RIP: 0010:lock_acquire+0x1c0/0x6e0 kernel/locking/lockdep.c:5445 Code: 00 00 fc ff df 80 3c 08 00 74 0c 48 c7 c7 68 a1 76 8a e8 c3 33 5d 00 48 83 3d d3 d7 19 09 00 0f 84 d0 04 00 00 4c 89 f7 57 9d <0f> 1f 44 00 00 65 48 8b 04 25 28 00 00 00 48 3b 44 24 40 0f 85 a9 RSP: 0018:ffffc90005387740 EFLAGS: 00000282 RAX: 1ffffffff14ed42d RBX: 0000000000000000 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000282 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1a702c9 R10: fffffbfff1a702c9 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000282 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] remove_vm_area+0x35/0x210 mm/vmalloc.c:2165 vm_remove_mappings mm/vmalloc.c:2201 [inline] __vunmap+0x2ed/0xa20 mm/vmalloc.c:2263 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:867 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1023 [inline] do_ipt_get_ctl+0x150d/0x1a10 net/ipv4/netfilter/ip_tables.c:1660 nf_getsockopt+0x2ab/0x2d0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x1f69/0x2870 net/ipv4/ip_sockglue.c:1778 tcp_getsockopt+0x1e2/0x2960 net/ipv4/tcp.c:3877 __sys_getsockopt+0x290/0x4c0 net/socket.c:2173 __do_sys_getsockopt net/socket.c:2188 [inline] __se_sys_getsockopt net/socket.c:2185 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2185 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x46096a Code: b8 34 01 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ed 88 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ca 88 fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007ffe144740d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007ffe14474100 RCX: 000000000046096a RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000074de60 R08: 00007ffe144740fc R09: 0000000000004000 R10: 00007ffe14474160 R11: 0000000000000212 R12: 00007ffe14474160 R13: 0000000000000003 R14: 000000000074ca20 R15: 0000000000000000