syzbot


BUG: soft lockup in kthreadd

Status: upstream: reported C repro on 2024/07/07 21:57
Bug presence: origin:lts
[Documentation on labels]
Reported-by: syzbot+6620297dd6e8ca5e3fe5@syzkaller.appspotmail.com
First crash: 62d, last: 41d
Bug presence (2)
Date Name Commit Repro Result
2024/07/28 lts (merge base) fd63fb84ed6d C [report] BUG: soft lockup in vfork
2024/07/28 upstream (ToT) 5437f30d3458 C Didn't crash
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in kthreadd 1 115d 115d 0/3 auto-obsoleted due to no activity on 2024/08/23 07:20
upstream INFO: rcu detected stall in kthreadd mm 2 135d 146d 0/27 auto-obsoleted due to no activity on 2024/07/25 04:06
Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/08/11 13:17 1h03m retest repro android13-5.15-lts report log
2024/07/21 22:16 14m retest repro android13-5.15-lts OK log

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 143s! [kthreadd:2]
Modules linked in:
CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.15.151-syzkaller-00127-g4edafe6c0231 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 2b 02 13 04 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc900000270c0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff92000004e1c RCX: 1ffffffff0d5aa9c
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8881f7038ad4
RBP: ffffc90000027170 R08: dffffc0000000000 R09: ffffed103ee0715b
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881f7038ad4 R14: 0000000000000001 R15: 1ffff92000004e20
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcbfee7be8 CR3: 000000011b746000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline]
 __pv_queued_spin_lock_slowpath+0x41b/0xc40 kernel/locking/qspinlock.c:473
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x4a8
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
 bpf_trace_run4+0x13f/0x270 kernel/trace/bpf_trace.c:1919
 __bpf_trace_mm_page_alloc+0xbf/0xf0 include/trace/events/kmem.h:201
 trace_mm_page_alloc include/trace/events/kmem.h:201 [inline]
 __alloc_pages+0x3cb/0x8f0 mm/page_alloc.c:5799
 __alloc_pages_node include/linux/gfp.h:591 [inline]
 alloc_pages_node include/linux/gfp.h:605 [inline]
 alloc_pages include/linux/gfp.h:618 [inline]
 __get_free_pages+0x10/0x30 mm/page_alloc.c:5814
 kasan_populate_vmalloc_pte+0x39/0x130 mm/kasan/shadow.c:266
 apply_to_pte_range mm/memory.c:2610 [inline]
 apply_to_pmd_range mm/memory.c:2654 [inline]
 apply_to_pud_range mm/memory.c:2690 [inline]
 apply_to_p4d_range mm/memory.c:2726 [inline]
 __apply_to_page_range+0x8dd/0xbe0 mm/memory.c:2760
 apply_to_page_range+0x3b/0x50 mm/memory.c:2779
 kasan_populate_vmalloc+0x65/0x70 mm/kasan/shadow.c:297
 alloc_vmap_area+0x192f/0x1a80 mm/vmalloc.c:1576
 __get_vm_area_node+0x158/0x360 mm/vmalloc.c:2439
 __vmalloc_node_range+0xe2/0x8d0 mm/vmalloc.c:3051
 alloc_thread_stack_node kernel/fork.c:254 [inline]
 dup_task_struct+0x416/0xc60 kernel/fork.c:944
 copy_process+0x5c4/0x3290 kernel/fork.c:2094
 kernel_clone+0x21e/0x9e0 kernel/fork.c:2662
 kernel_thread+0x168/0x1e0 kernel/fork.c:2723
 create_kthread kernel/kthread.c:360 [inline]
 kthreadd+0x35b/0x490 kernel/kthread.c:715
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/28 13:03 android13-5.15-lts 4edafe6c0231 46eb10b7 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in kthreadd
2024/07/07 21:56 android13-5.15-lts 9044d25b8ff5 2a40360c .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in kthreadd
* Struck through repros no longer work on HEAD.