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BUG: soft lockup in sys_clone

Status: closed as invalid on 2020/05/29 21:04
Subsystems: kernel
[Documentation on labels]
First crash: 2297d, last: 2293d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 BUG: soft lockup in sys_clone 1 1 729d 729d 0/2 auto-obsoleted due to no activity on 2024/10/06 12:58
android-5-10 BUG: soft lockup in sys_clone (2) 1 1 304d 304d 0/2 auto-obsoleted due to no activity on 2025/12/06 02:03
android-5-10 BUG: soft lockup in sys_clone (4) 1 1 31d 31d 0/2 premoderation: reported on 2026/06/07 05:26
android-5-10 BUG: soft lockup in sys_clone (3) 1 1 156d 156d 0/2 auto-obsoleted due to no activity on 2026/05/02 19:39
upstream INFO: rcu detected stall in sys_clone (8) mm 1 C error 454 2d15h 831d 0/29 upstream: reported C repro on 2024/03/29 00:16
linux-5.15 INFO: rcu detected stall in sys_clone (2) missing-backport origin:upstream 1 C done 152 25m 833d 0/3 upstream: reported C repro on 2024/03/27 00:16
android-5-15 BUG: soft lockup in sys_clone origin:upstream 1 C error 18 665d 809d 0/2 auto-obsoleted due to no activity on 2024/12/19 12:14

Sample crash report:
watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz-executor.1:373]
Modules linked in:
irq event stamp: 2330844
hardirqs last  enabled at (2330843): [<ffffffff81004721>] trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41
hardirqs last disabled at (2330844): [<ffffffff8100473d>] trace_hardirqs_off_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:42
softirqs last  enabled at (2330842): [<ffffffff85c00673>] __do_softirq+0x673/0x950 kernel/softirq.c:319
softirqs last disabled at (2330835): [<ffffffff81157f28>] invoke_softirq kernel/softirq.c:373 [inline]
softirqs last disabled at (2330835): [<ffffffff81157f28>] irq_exit+0x178/0x1a0 kernel/softirq.c:413
CPU: 1 PID: 373 Comm: syz-executor.1 Not tainted 5.6.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:write_comp_data+0x9/0x80 kernel/kcov.c:218
Code: 12 00 00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 2e 0f 1f 84 00 00 00 00 00 65 4c 8b 04 25 00 0f 02 00 <65> 8b 05 78 b8 c2 7e a9 00 01 1f 00 74 0f f6 c4 01 74 5b 41 80 b8
RSP: 0018:ffff8881adcef898 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: ffff8881cc754980 RBX: 0000000000000001 RCX: ffffffff8134f3bf
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000005
RBP: ffff8881adcef978 R08: ffff8881cc754980 R09: fffffbfff1266e8a
R10: fffffbfff1266e89 R11: ffffffff8933744f R12: 0000000000000000
R13: 0000000000000001 R14: ffff8881cf00f440 R15: ffff8881db333e00
FS:  0000000002b44940(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005573274138b8 CR3: 00000001ae31c000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 csd_lock_wait kernel/smp.c:109 [inline]
 smp_call_function_single+0x2df/0x3a0 kernel/smp.c:311
 smp_call_function_many_cond+0x25e/0x900 kernel/smp.c:439
 flush_tlb_others arch/x86/include/asm/paravirt.h:68 [inline]
 flush_tlb_mm_range+0x1e8/0x3e0 arch/x86/mm/tlb.c:798
 dup_mmap kernel/fork.c:616 [inline]
 dup_mm+0xcc6/0x1180 kernel/fork.c:1360
 copy_mm kernel/fork.c:1416 [inline]
 copy_process+0x26ef/0x6640 kernel/fork.c:2081
 _do_fork+0x12d/0xfd0 kernel/fork.c:2430
 __do_sys_clone kernel/fork.c:2585 [inline]
 __se_sys_clone kernel/fork.c:2566 [inline]
 __x64_sys_clone+0x182/0x210 kernel/fork.c:2566
 do_syscall_64+0xb6/0x5a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45ae1a
Code: f7 d8 64 89 04 25 d4 02 00 00 64 4c 8b 0c 25 10 00 00 00 31 d2 4d 8d 91 d0 02 00 00 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 f5 00 00 00 85 c0 41 89 c5 0f 85 fc 00 00
RSP: 002b:00007ffd04feb7b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffd04feb7b0 RCX: 000000000045ae1a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffd04feb7f0 R08: 0000000000000001 R09: 0000000002b44940
R10: 0000000002b44c10 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffd04feb840
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 94 Comm: kworker/0:2 Not tainted 5.6.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
RIP: 0010:__sanitizer_cov_trace_pc+0x45/0x60 kernel/kcov.c:202
Code: 0e 80 e6 01 74 34 80 b8 d4 12 00 00 00 74 2b 8b 90 b0 12 00 00 83 fa 02 75 20 48 8b 88 b8 12 00 00 8b 80 b4 12 00 00 48 8b 11 <48> 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 66 2e 0f 1f 84
RSP: 0018:ffff8881db2099d8 EFLAGS: 00000046
RAX: 0000000000040000 RBX: 00000000000000fe RCX: ffffc90000022000
RDX: 000000000003ffff RSI: ffffffff84ba5b85 RDI: 0000000000000001
RBP: ffff8881c64e7ea0 R08: ffff8881d6f6b100 R09: ffffed10399d18c1
R10: ffffed10399d18c0 R11: ffff8881cce8c600 R12: 000000000000000b
R13: 0000000000000025 R14: 00000000000003db R15: 0000000000000013
FS:  0000000000000000(0000) GS:ffff8881db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557327418258 CR3: 00000001ae31c000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 midibuf_message_length sound/usb/line6/midibuf.c:31 [inline]
 line6_midibuf_read+0x1e5/0xa30 sound/usb/line6/midibuf.c:160
 line6_data_received+0x318/0x520 sound/usb/line6/driver.c:305
 __usb_hcd_giveback_urb+0x29a/0x550 drivers/usb/core/hcd.c:1650
 usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1716
 dummy_timer+0x1258/0x32ae drivers/usb/gadget/udc/dummy_hcd.c:1966
 call_timer_fn+0x195/0x6f0 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x5f9/0x1500 kernel/time/timer.c:1786
 __do_softirq+0x21e/0x950 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x178/0x1a0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x141/0x540 arch/x86/kernel/apic/apic.c:1146
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:85 [inline]
RIP: 0010:console_unlock+0xa6b/0xca0 kernel/printk/printk.c:2481
Code: 00 89 ee 48 c7 c7 60 43 14 87 e8 10 c3 03 00 65 ff 0d a1 ef d8 7e e9 b5 f9 ff ff e8 af 36 16 00 e8 aa 7f 1b 00 ff 74 24 30 9d <e9> fd fd ff ff e8 9b 36 16 00 48 8d 7d 08 48 89 f8 48 c1 e8 03 42
RSP: 0018:ffff8881d58c6d80 EFLAGS: 00000216 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: 0000000000000200 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8881d6f6b94c
RBP: 0000000000000000 R08: ffff8881d6f6b100 R09: fffffbfff1266e85
R10: fffffbfff1266e84 R11: ffffffff89337427 R12: ffffffff82a07730
R13: ffffffff874d4810 R14: 0000000000000052 R15: dffffc0000000000
 vprintk_emit+0x171/0x3d0 kernel/printk/printk.c:1996
 dev_vprintk_emit+0x4fc/0x541 drivers/base/core.c:3616
 dev_printk_emit+0xba/0xf1 drivers/base/core.c:3627
 __dev_printk+0x1db/0x203 drivers/base/core.c:3639
 _dev_err+0xd7/0x109 drivers/base/core.c:3682
 hub_configure drivers/usb/core/hub.c:1678 [inline]
 hub_probe.cold+0x903/0x2a22 drivers/usb/core/hub.c:1876
 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374
 really_probe+0x290/0xac0 drivers/base/dd.c:551
 driver_probe_device+0x223/0x350 drivers/base/dd.c:724
 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x217/0x390 drivers/base/dd.c:897
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0x1459/0x1bf0 drivers/base/core.c:2500
 usb_set_configuration+0xe47/0x17d0 drivers/usb/core/message.c:2023
 usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241
 usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272
 really_probe+0x290/0xac0 drivers/base/dd.c:551
 driver_probe_device+0x223/0x350 drivers/base/dd.c:724
 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
 __device_attach+0x217/0x390 drivers/base/dd.c:897
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0x1459/0x1bf0 drivers/base/core.c:2500
 usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2548
 hub_port_connect drivers/usb/core/hub.c:5195 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
 port_event drivers/usb/core/hub.c:5481 [inline]
 hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5563
 process_one_work+0x94b/0x1620 kernel/workqueue.c:2264
 worker_thread+0x96/0xe20 kernel/workqueue.c:2410
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/03/27 19:35 https://github.com/google/kasan.git usb-fuzzer e17994d1e7b1 831e9a81 .config console log report ci2-upstream-usb
2020/03/27 15:06 https://github.com/google/kasan.git usb-fuzzer e17994d1e7b1 831e9a81 .config console log report ci2-upstream-usb
2020/03/23 20:25 https://github.com/google/kasan.git usb-fuzzer e17994d1e7b1 84f999d6 .config console log report ci2-upstream-usb
* Struck through repros no longer work on HEAD.