=============================
WARNING: suspicious RCU usage
5.1.0-rc3-319004-g43151d6 #6 Not tainted
-----------------------------
include/linux/rcupdate.h:267 Illegal context switch in RCU read-side critical section!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by udevd/26828:
 #0: 00000000c4013af4 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1407 [inline]
 #0: 00000000c4013af4 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file.isra.0+0x37b/0x2370 fs/exec.c:1750
 #1: 000000001ddd3982 (rcu_read_lock){....}, at: arch_static_branch arch/x86/include/asm/jump_label.h:23 [inline]
 #1: 000000001ddd3982 (rcu_read_lock){....}, at: mem_cgroup_disabled include/linux/memcontrol.h:333 [inline]
 #1: 000000001ddd3982 (rcu_read_lock){....}, at: get_mem_cgroup_from_mm+0x66/0x570 mm/memcontrol.c:838
 #2: 00000000c32710b8 ((&toneport->timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:170 [inline]
 #2: 00000000c32710b8 ((&toneport->timer)){+.-.}, at: call_timer_fn+0xce/0x5f0 kernel/time/timer.c:1315

stack backtrace:
CPU: 1 PID: 26828 Comm: udevd Not tainted 5.1.0-rc3-319004-g43151d6 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe8/0x16e lib/dump_stack.c:113
 rcu_preempt_sleep_check include/linux/rcupdate.h:267 [inline]
 rcu_preempt_sleep_check include/linux/rcupdate.h:265 [inline]
 ___might_sleep+0x1b6/0x280 kernel/sched/core.c:6155
 __mutex_lock_common kernel/locking/mutex.c:908 [inline]
 __mutex_lock+0xcd/0x12b0 kernel/locking/mutex.c:1072
 line6_pcm_acquire+0x35/0x210 sound/usb/line6/pcm.c:311
 call_timer_fn+0x161/0x5f0 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x58b/0x1400 kernel/time/timer.c:1694
 __do_softirq+0x22a/0x8cd kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x187/0x1b0 kernel/softirq.c:414
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0xfe/0x4a0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:task_css include/linux/cgroup.h:480 [inline]
RIP: 0010:mem_cgroup_from_task mm/memcontrol.c:822 [inline]
RIP: 0010:get_mem_cgroup_from_mm mm/memcontrol.c:851 [inline]
RIP: 0010:get_mem_cgroup_from_mm+0x138/0x570 mm/memcontrol.c:834
Code: 0f 85 1b 04 00 00 4d 8b af 90 10 00 00 e8 a0 57 b1 ff 85 c0 0f 85 bd 00 00 00 49 8d 7d 20 48 89 f8 48 c1 e8 03 42 80 3c 20 00 <0f> 85 e7 03 00 00 4d 8b 7d 20 4d 85 ff 0f 84 b6 01 00 00 49 8d 7f
RSP: 0018:ffff88808c6a7c88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff2301a48 RBX: ffff88809a55e800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff917d62e0 RDI: ffffffff9180d240
RBP: 1ffff110118d4f94 R08: 000000003e31d3a2 R09: ffffed1015a25c28
R10: ffffed1015a25c27 R11: ffff8880ad12e13b R12: dffffc0000000000
R13: ffffffff9180d220 R14: ffff88809a55ed40 R15: ffff888097ab1880
 get_mem_cgroup_from_current mm/memcontrol.c:897 [inline]
 memcg_kmem_get_cache+0x142/0x5d0 mm/memcontrol.c:2548
 slab_pre_alloc_hook mm/slab.h:425 [inline]
 slab_alloc_node mm/slub.c:2682 [inline]
 slab_alloc mm/slub.c:2764 [inline]
 kmem_cache_alloc+0x12f/0x270 mm/slub.c:2769
 prepare_creds+0x2a/0x330 kernel/cred.c:254
 prepare_exec_creds+0x12/0xf0 kernel/cred.c:299
 prepare_bprm_creds fs/exec.c:1410 [inline]
 __do_execve_file.isra.0+0x398/0x2370 fs/exec.c:1750
 do_execveat_common fs/exec.c:1865 [inline]
 do_execve fs/exec.c:1882 [inline]
 __do_sys_execve fs/exec.c:1958 [inline]
 __se_sys_execve fs/exec.c:1953 [inline]
 __x64_sys_execve+0x8f/0xb0 fs/exec.c:1953
 do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f8f9f77e207
Code: 77 19 f4 48 89 d7 44 89 c0 0f 05 48 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 f7 d8 64 41 89 01 eb df b8 3b 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 02 f3 c3 48 8b 15 00 8c 2d 00 f7 d8 64 89 02
RSP: 002b:00007ffe78dc7c58 EFLAGS: 00000202 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f8f9f77e207
RDX: 000000000062b6d0 RSI: 00007ffe78dc7d50 RDI: 00007ffe78dc9160
RBP: 0000000000625500 R08: 00000000000015d3 R09: 00000000000015d3
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000062b6d0
R13: 0000000000000008 R14: 0000000000626250 R15: 0000000000000007
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908
in_atomic(): 1, irqs_disabled(): 0, pid: 26828, name: udevd
3 locks held by udevd/26828:
 #0: 00000000c4013af4 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1407 [inline]
 #0: 00000000c4013af4 (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file.isra.0+0x37b/0x2370 fs/exec.c:1750
 #1: 000000001ddd3982 (rcu_read_lock){....}, at: arch_static_branch arch/x86/include/asm/jump_label.h:23 [inline]
 #1: 000000001ddd3982 (rcu_read_lock){....}, at: mem_cgroup_disabled include/linux/memcontrol.h:333 [inline]
 #1: 000000001ddd3982 (rcu_read_lock){....}, at: get_mem_cgroup_from_mm+0x66/0x570 mm/memcontrol.c:838
 #2: 00000000c32710b8 ((&toneport->timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:170 [inline]
 #2: 00000000c32710b8 ((&toneport->timer)){+.-.}, at: call_timer_fn+0xce/0x5f0 kernel/time/timer.c:1315
CPU: 1 PID: 26828 Comm: udevd Not tainted 5.1.0-rc3-319004-g43151d6 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe8/0x16e lib/dump_stack.c:113
 ___might_sleep.cold+0x11c/0x136 kernel/sched/core.c:6190
 __mutex_lock_common kernel/locking/mutex.c:908 [inline]
 __mutex_lock+0xcd/0x12b0 kernel/locking/mutex.c:1072
 line6_pcm_acquire+0x35/0x210 sound/usb/line6/pcm.c:311
 call_timer_fn+0x161/0x5f0 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x58b/0x1400 kernel/time/timer.c:1694
 __do_softirq+0x22a/0x8cd kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x187/0x1b0 kernel/softirq.c:414
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0xfe/0x4a0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:task_css include/linux/cgroup.h:480 [inline]
RIP: 0010:mem_cgroup_from_task mm/memcontrol.c:822 [inline]
RIP: 0010:get_mem_cgroup_from_mm mm/memcontrol.c:851 [inline]
RIP: 0010:get_mem_cgroup_from_mm+0x138/0x570 mm/memcontrol.c:834
Code: 0f 85 1b 04 00 00 4d 8b af 90 10 00 00 e8 a0 57 b1 ff 85 c0 0f 85 bd 00 00 00 49 8d 7d 20 48 89 f8 48 c1 e8 03 42 80 3c 20 00 <0f> 85 e7 03 00 00 4d 8b 7d 20 4d 85 ff 0f 84 b6 01 00 00 49 8d 7f
RSP: 0018:ffff88808c6a7c88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff2301a48 RBX: ffff88809a55e800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff917d62e0 RDI: ffffffff9180d240
RBP: 1ffff110118d4f94 R08: 000000003e31d3a2 R09: ffffed1015a25c28
R10: ffffed1015a25c27 R11: ffff8880ad12e13b R12: dffffc0000000000
R13: ffffffff9180d220 R14: ffff88809a55ed40 R15: ffff888097ab1880
 get_mem_cgroup_from_current mm/memcontrol.c:897 [inline]
 memcg_kmem_get_cache+0x142/0x5d0 mm/memcontrol.c:2548
 slab_pre_alloc_hook mm/slab.h:425 [inline]
 slab_alloc_node mm/slub.c:2682 [inline]
 slab_alloc mm/slub.c:2764 [inline]
 kmem_cache_alloc+0x12f/0x270 mm/slub.c:2769
 prepare_creds+0x2a/0x330 kernel/cred.c:254
 prepare_exec_creds+0x12/0xf0 kernel/cred.c:299
 prepare_bprm_creds fs/exec.c:1410 [inline]
 __do_execve_file.isra.0+0x398/0x2370 fs/exec.c:1750
 do_execveat_common fs/exec.c:1865 [inline]
 do_execve fs/exec.c:1882 [inline]
 __do_sys_execve fs/exec.c:1958 [inline]
 __se_sys_execve fs/exec.c:1953 [inline]
 __x64_sys_execve+0x8f/0xb0 fs/exec.c:1953
 do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f8f9f77e207
Code: 77 19 f4 48 89 d7 44 89 c0 0f 05 48 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 f7 d8 64 41 89 01 eb df b8 3b 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 02 f3 c3 48 8b 15 00 8c 2d 00 f7 d8 64 89 02
RSP: 002b:00007ffe78dc7c58 EFLAGS: 00000202 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f8f9f77e207
RDX: 000000000062b6d0 RSI: 00007ffe78dc7d50 RDI: 00007ffe78dc9160
RBP: 0000000000625500 R08: 00000000000015d3 R09: 00000000000015d3
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000062b6d0
R13: 0000000000000008 R14: 0000000000626250 R15: 0000000000000007
==================================================================
BUG: KASAN: null-ptr-deref in memset include/linux/string.h:337 [inline]
BUG: KASAN: null-ptr-deref in submit_audio_out_urb+0x91e/0x1780 sound/usb/line6/playback.c:246
Write of size 20 at addr 0000000000000010 by task udevd/26828

CPU: 1 PID: 26828 Comm: udevd Tainted: G        W         5.1.0-rc3-319004-g43151d6 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe8/0x16e lib/dump_stack.c:113
 kasan_report.cold+0x5/0x3c mm/kasan/report.c:321
 memset+0x20/0x40 mm/kasan/common.c:115
 memset include/linux/string.h:337 [inline]
 submit_audio_out_urb+0x91e/0x1780 sound/usb/line6/playback.c:246
 line6_submit_audio_out_all_urbs+0xce/0x120 sound/usb/line6/playback.c:295
 line6_stream_start+0x15b/0x1f0 sound/usb/line6/pcm.c:199
 line6_pcm_acquire+0x139/0x210 sound/usb/line6/pcm.c:322
 call_timer_fn+0x161/0x5f0 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x58b/0x1400 kernel/time/timer.c:1694
 __do_softirq+0x22a/0x8cd kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x187/0x1b0 kernel/softirq.c:414
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0xfe/0x4a0 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:task_css include/linux/cgroup.h:480 [inline]
RIP: 0010:mem_cgroup_from_task mm/memcontrol.c:822 [inline]
RIP: 0010:get_mem_cgroup_from_mm mm/memcontrol.c:851 [inline]
RIP: 0010:get_mem_cgroup_from_mm+0x138/0x570 mm/memcontrol.c:834
Code: 0f 85 1b 04 00 00 4d 8b af 90 10 00 00 e8 a0 57 b1 ff 85 c0 0f 85 bd 00 00 00 49 8d 7d 20 48 89 f8 48 c1 e8 03 42 80 3c 20 00 <0f> 85 e7 03 00 00 4d 8b 7d 20 4d 85 ff 0f 84 b6 01 00 00 49 8d 7f
RSP: 0018:ffff88808c6a7c88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff2301a48 RBX: ffff88809a55e800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff917d62e0 RDI: ffffffff9180d240
RBP: 1ffff110118d4f94 R08: 000000003e31d3a2 R09: ffffed1015a25c28
R10: ffffed1015a25c27 R11: ffff8880ad12e13b R12: dffffc0000000000
R13: ffffffff9180d220 R14: ffff88809a55ed40 R15: ffff888097ab1880
 get_mem_cgroup_from_current mm/memcontrol.c:897 [inline]
 memcg_kmem_get_cache+0x142/0x5d0 mm/memcontrol.c:2548
 slab_pre_alloc_hook mm/slab.h:425 [inline]
 slab_alloc_node mm/slub.c:2682 [inline]
 slab_alloc mm/slub.c:2764 [inline]
 kmem_cache_alloc+0x12f/0x270 mm/slub.c:2769
 prepare_creds+0x2a/0x330 kernel/cred.c:254
 prepare_exec_creds+0x12/0xf0 kernel/cred.c:299
 prepare_bprm_creds fs/exec.c:1410 [inline]
 __do_execve_file.isra.0+0x398/0x2370 fs/exec.c:1750
 do_execveat_common fs/exec.c:1865 [inline]
 do_execve fs/exec.c:1882 [inline]
 __do_sys_execve fs/exec.c:1958 [inline]
 __se_sys_execve fs/exec.c:1953 [inline]
 __x64_sys_execve+0x8f/0xb0 fs/exec.c:1953
 do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f8f9f77e207
Code: 77 19 f4 48 89 d7 44 89 c0 0f 05 48 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 f7 d8 64 41 89 01 eb df b8 3b 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 02 f3 c3 48 8b 15 00 8c 2d 00 f7 d8 64 89 02
RSP: 002b:00007ffe78dc7c58 EFLAGS: 00000202 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007f8f9f77e207
RDX: 000000000062b6d0 RSI: 00007ffe78dc7d50 RDI: 00007ffe78dc9160
RBP: 0000000000625500 R08: 00000000000015d3 R09: 00000000000015d3
R10: 0000000000000000 R11: 0000000000000202 R12: 000000000062b6d0
R13: 0000000000000008 R14: 0000000000626250 R15: 0000000000000007
==================================================================