INFO: rcu detected stall in snd_rawmidi_write (6)

Status: auto-obsoleted due to no activity on 2026/04/20 03:16
Subsystems: sound mm
[Documentation on labels]
First crash: 426d, last: 203d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in snd_rawmidi_write (4) sound 1 1 1070d 1070d 0/29 auto-obsoleted due to no activity on 2023/12/05 12:57
upstream INFO: rcu detected stall in snd_rawmidi_write mm 1 1 2442d 2442d 0/29 closed as invalid on 2019/12/04 14:04
linux-5.15 INFO: rcu detected stall in snd_rawmidi_write 1 2 284d 297d 0/3 auto-obsoleted due to no activity on 2026/02/07 16:16
upstream INFO: rcu detected stall in snd_rawmidi_write (3) block 1 1 1278d 1278d 0/29 auto-obsoleted due to no activity on 2023/04/20 22:18
upstream INFO: rcu detected stall in snd_rawmidi_write (2) sound 1 2 1454d 1541d 0/29 auto-obsoleted due to no activity on 2022/11/16 04:30
upstream INFO: rcu detected stall in snd_rawmidi_write (5) sound 1 2 559d 600d 0/29 auto-obsoleted due to no activity on 2025/04/29 04:59

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5839/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=29973, q=770 ncpus=2)
task:syz-executor    state:R  running task     stack:21592 pid:5839  tgid:5839  ppid:5818   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x149b/0x4fd0 kernel/sched/core.c:6867
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7051
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 copy_pte_range mm/memory.c:1331 [inline]
 copy_pmd_range+0x74f2/0x7e00 mm/memory.c:1392
 copy_pud_range mm/memory.c:1429 [inline]
 copy_p4d_range mm/memory.c:1453 [inline]
 copy_page_range+0xb88/0x11d0 mm/memory.c:1535
 dup_mmap+0xf4a/0x1b80 mm/mmap.c:1827
 dup_mm kernel/fork.c:1529 [inline]
 copy_mm+0x13c/0x4b0 kernel/fork.c:1581
 copy_process+0x165d/0x3950 kernel/fork.c:2221
 kernel_clone+0x21e/0x820 kernel/fork.c:2651
 __do_sys_clone kernel/fork.c:2792 [inline]
 __se_sys_clone kernel/fork.c:2776 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2776
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc55fd85e93
RSP: 002b:00007fff9432d808 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc55fd85e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555575c967d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000004fb44 R15: 00007fff9432d9a0
 </TASK>
rcu: rcu_preempt kthread starved for 1883 jiffies! g29973 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27568 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5260 [inline]
 __schedule+0x149b/0x4fd0 kernel/sched/core.c:6867
 __schedule_loop kernel/sched/core.c:6949 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6964
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8802 Comm: syz.9.545 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:37 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline]
RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline]
RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:212
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 e9 7b c2 9d ff cc f3 0f 1e fa 89 f6 31 d2 e9 c2 53 55 03 66
RSP: 0018:ffffc90000007e50 EFLAGS: 00000046
RAX: 000000000000ef49 RBX: ffff8880b8623e40 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 000000000000ef49 RDI: 0000000000000838
RBP: 0000000000000000 R08: ffffffff81aecf75 R09: ffffffff998fd508
R10: 0000000000000003 R11: ffffffff81715640 R12: 000000000ffffe52
R13: dffffc0000000000 R14: 000000000000ef49 R15: 0000000000000020
FS:  00007f460e6476c0(0000) GS:ffff888125e1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000031be5000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 apic_write arch/x86/include/asm/apic.h:409 [inline]
 lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:418
 clockevents_program_event+0x1c9/0x350 kernel/time/clockevents.c:334
 hrtimer_interrupt+0x620/0xaa0 kernel/time/hrtimer.c:1916
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x3e0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:194
Code: f7 e8 0d c0 41 f6 f7 c3 00 02 00 00 74 05 e8 b0 ee 6b f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 74 c5 33 f6 65 8b 05 0d 68 23 07 85 c0 74 18 5b 41 5e e9 dc 58
RSP: 0018:ffffc90003197828 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000286 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8d79361f RDI: 0000000000000001
RBP: ffffffff99bb1570 R08: ffffffff8f822e77 R09: 1ffffffff1f045ce
R10: dffffc0000000000 R11: fffffbfff1f045cf R12: ffff888030a9e440
R13: ffff888030a9e428 R14: ffffffff99bb1578 R15: dffffc0000000000
 debug_object_assert_init+0x20e/0x380 lib/debugobjects.c:1009
 debug_timer_assert_init kernel/time/timer.c:803 [inline]
 debug_assert_init kernel/time/timer.c:848 [inline]
 __mod_timer+0x4a/0xf30 kernel/time/timer.c:1025
 schedule_timeout+0x126/0x270 kernel/time/sleep_timeout.c:98
 snd_rawmidi_write+0x3a8/0xbc0 sound/core/rawmidi.c:1616
 do_loop_readv_writev fs/read_write.c:850 [inline]
 vfs_writev+0x4b6/0x960 fs/read_write.c:1059
 do_writev+0x14d/0x2d0 fs/read_write.c:1103
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f460d78f749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f460e647038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f460d9e5fa0 RCX: 00007f460d78f749
RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000007
RBP: 00007f460d813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f460d9e6038 R14: 00007f460d9e5fa0 R15: 00007ffd8a911cd8
 </TASK>

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/20 03:13 upstream 24d479d26b25 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in snd_rawmidi_write
2025/12/24 14:48 upstream b927546677c8 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in snd_rawmidi_write
2025/10/27 18:32 upstream dcb6fa37fd7b fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in snd_rawmidi_write
2025/08/21 08:34 upstream 41cd3fd15263 0b9605c8 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in snd_rawmidi_write
2025/08/09 04:48 upstream 038d61fd6422 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in snd_rawmidi_write
2025/06/28 18:32 upstream 35e261cd95dd fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in snd_rawmidi_write
2025/06/10 16:15 upstream f09079bd04a9 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in snd_rawmidi_write
2025/06/24 04:34 linux-next f817b6dd2b62 1a7fb460 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in snd_rawmidi_write
* Struck through repros no longer work on HEAD.