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possible deadlock in rcu_report_exp_cpu_mult

Status: fixed on 2024/05/22 23:36
Subsystems: net bpf
[Documentation on labels]
Reported-by: syzbot+c4f4d25859c2e5859988@syzkaller.appspotmail.com
Fix commit: ff9105993240 bpf, sockmap: Prevent lock inversion deadlock in map delete elem
First crash: 271d, last: 231d
Cause bisection: introduced by (bisect log) :
commit ee042be16cb455116d0fe99b77c6bc8baf87c8c6
Author: Namhyung Kim <namhyung@kernel.org>
Date: Tue Mar 22 18:57:09 2022 +0000

  locking: Apply contention tracepoints in the slow path

Crash: possible deadlock in scheduler_tick (log)
Repro: C syz .config
  
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[syzbot] [bpf?] [net?] possible deadlock in rcu_report_exp_cpu_mult 3 (6) 2024/04/20 14:51
[PATCH] bpf, sockmap: fix deadlock in rcu_report_exp_cpu_mult 7 (7) 2024/03/29 15:52
[syzbot] [kernel?] possible deadlock in console_flush_all (2) 13 (16) 2024/03/27 14:25
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in rcu_report_exp_cpu_mult C done 7 246d 271d 3/3 fixed on 2024/05/16 16:53
▶ ▼ Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/03/22 00:17 24m eadavis@qq.com patch https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git master OK log
2024/03/21 00:25 24m eadavis@qq.com patch https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git master report log

Sample crash report:
=====================================================
WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted
-----------------------------------------------------
rcu_exp_gp_kthr/18 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire:
ffff88802d7c1a00 (&stab->lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88802d7c1a00 (&stab->lock){+...}-{2:2}, at: __sock_map_delete net/core/sock_map.c:414 [inline]
ffff88802d7c1a00 (&stab->lock){+...}-{2:2}, at: sock_map_delete_elem+0xc8/0x150 net/core/sock_map.c:446

and this task is already holding:
ffffffff8d7bbd58 (rcu_node_0){-.-.}-{2:2}, at: sync_rcu_exp_done_unlocked+0xc/0x90 kernel/rcu/tree_exp.h:169
which would create a new lock dependency:
 (rcu_node_0){-.-.}-{2:2} -> (&stab->lock){+...}-{2:2}

but this new dependency connects a HARDIRQ-irq-safe lock:
 (rcu_node_0){-.-.}-{2:2}

... which became HARDIRQ-irq-safe at:
  lock_acquire kernel/locking/lockdep.c:5754 [inline]
  lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
  __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
  _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
  rcu_report_exp_cpu_mult+0x1c/0x2b0 kernel/rcu/tree_exp.h:238
  csd_do_func kernel/smp.c:133 [inline]
  __flush_smp_call_function_queue+0x41f/0x8c0 kernel/smp.c:542
  __sysvec_call_function_single+0x8c/0x3a0 arch/x86/kernel/smp.c:271
  instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
  sysvec_call_function_single+0x90/0xb0 arch/x86/kernel/smp.c:266
  asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
  __sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:223
  update_event_printk kernel/trace/trace_events.c:2766 [inline]
  trace_event_eval_update+0x3fe/0xfe0 kernel/trace/trace_events.c:2922
  trace_insert_eval_map kernel/trace/trace.c:6294 [inline]
  eval_map_work_func+0x3d/0x50 kernel/trace/trace.c:10069
  process_one_work+0x9a9/0x1a60 kernel/workqueue.c:3254
  process_scheduled_works kernel/workqueue.c:3335 [inline]
  worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
  kthread+0x2c1/0x3a0 kernel/kthread.c:388
  ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

to a HARDIRQ-irq-unsafe lock:
 (&stab->lock){+...}-{2:2}

... which became HARDIRQ-irq-unsafe at:
...
  lock_acquire kernel/locking/lockdep.c:5754 [inline]
  lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
  __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
  _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178
  spin_lock_bh include/linux/spinlock.h:356 [inline]
  __sock_map_delete net/core/sock_map.c:414 [inline]
  sock_map_delete_elem+0xc8/0x150 net/core/sock_map.c:446
  ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
  __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
  bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
  __bpf_prog_run include/linux/filter.h:657 [inline]
  bpf_prog_run include/linux/filter.h:664 [inline]
  __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
  bpf_trace_run2+0x151/0x420 kernel/trace/bpf_trace.c:2420
  __bpf_trace_contention_end+0xca/0x110 include/trace/events/lock.h:122
  trace_contention_end+0xce/0x120 include/trace/events/lock.h:122
  __mutex_lock_common kernel/locking/mutex.c:617 [inline]
  __mutex_lock+0x19c/0x9c0 kernel/locking/mutex.c:752
  futex_cleanup_begin kernel/futex/core.c:1091 [inline]
  futex_exit_release+0x2a/0x220 kernel/futex/core.c:1143
  exit_mm_release+0x19/0x30 kernel/fork.c:1652
  exit_mm kernel/exit.c:542 [inline]
  do_exit+0x865/0x2be0 kernel/exit.c:865
  do_group_exit+0xd3/0x2a0 kernel/exit.c:1027
  __do_sys_exit_group kernel/exit.c:1038 [inline]
  __se_sys_exit_group kernel/exit.c:1036 [inline]
  __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1036
  do_syscall_x64 arch/x86/entry/common.c:52 [inline]
  do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
  entry_SYSCALL_64_after_hwframe+0x6d/0x75

other info that might help us debug this:

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&stab->lock);
                               local_irq_disable();
                               lock(rcu_node_0);
                               lock(&stab->lock);
  <Interrupt>
    lock(rcu_node_0);

 *** DEADLOCK ***

2 locks held by rcu_exp_gp_kthr/18:
 #0: ffffffff8d7bbd58 (rcu_node_0){-.-.}-{2:2}, at: sync_rcu_exp_done_unlocked+0xc/0x90 kernel/rcu/tree_exp.h:169
 #1: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 #1: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
 #1: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline]
 #1: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0xe4/0x420 kernel/trace/bpf_trace.c:2420

the dependencies between HARDIRQ-irq-safe lock and the holding lock:
-> (rcu_node_0){-.-.}-{2:2} {
   IN-HARDIRQ-W at:
                    lock_acquire kernel/locking/lockdep.c:5754 [inline]
                    lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
                    __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                    _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
                    rcu_report_exp_cpu_mult+0x1c/0x2b0 kernel/rcu/tree_exp.h:238
                    csd_do_func kernel/smp.c:133 [inline]
                    __flush_smp_call_function_queue+0x41f/0x8c0 kernel/smp.c:542
                    __sysvec_call_function_single+0x8c/0x3a0 arch/x86/kernel/smp.c:271
                    instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
                    sysvec_call_function_single+0x90/0xb0 arch/x86/kernel/smp.c:266
                    asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
                    __sanitizer_cov_trace_pc+0x58/0x60 kernel/kcov.c:223
                    update_event_printk kernel/trace/trace_events.c:2766 [inline]
                    trace_event_eval_update+0x3fe/0xfe0 kernel/trace/trace_events.c:2922
                    trace_insert_eval_map kernel/trace/trace.c:6294 [inline]
                    eval_map_work_func+0x3d/0x50 kernel/trace/trace.c:10069
                    process_one_work+0x9a9/0x1a60 kernel/workqueue.c:3254
                    process_scheduled_works kernel/workqueue.c:3335 [inline]
                    worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416
                    kthread+0x2c1/0x3a0 kernel/kthread.c:388
                    ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
                    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
   IN-SOFTIRQ-W at:
                    lock_acquire kernel/locking/lockdep.c:5754 [inline]
                    lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
                    __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                    _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
                    rcu_report_qs_rdp kernel/rcu/tree.c:2018 [inline]
                    rcu_check_quiescent_state kernel/rcu/tree.c:2100 [inline]
                    rcu_core+0x213/0x16b0 kernel/rcu/tree.c:2455
                    __do_softirq+0x218/0x8de kernel/softirq.c:554
                    invoke_softirq kernel/softirq.c:428 [inline]
                    __irq_exit_rcu kernel/softirq.c:633 [inline]
                    irq_exit_rcu+0xb9/0x120 kernel/softirq.c:645
                    instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
                    sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043
                    asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
                    check_kcov_mode kernel/kcov.c:175 [inline]
                    __sanitizer_cov_trace_pc+0x33/0x60 kernel/kcov.c:207
                    deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline]
                    unwind_next_frame+0x1bb2/0x23a0 arch/x86/kernel/unwind_orc.c:648
                    arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25
                    stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
                    kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
                    kasan_save_track+0x14/0x30 mm/kasan/common.c:68
                    poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
                    __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
                    kmalloc include/linux/slab.h:628 [inline]
                    kzalloc include/linux/slab.h:749 [inline]
                    ddebug_add_module+0xd7/0x950 lib/dynamic_debug.c:1240
                    dynamic_debug_init+0x192/0x4b0 lib/dynamic_debug.c:1446
                    do_one_initcall+0x128/0x690 init/main.c:1241
                    do_pre_smp_initcalls init/main.c:1347 [inline]
                    kernel_init_freeable+0x400/0xc40 init/main.c:1539
                    kernel_init+0x1c/0x2a0 init/main.c:1439
                    ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
                    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
   INITIAL USE at:
                   lock_acquire kernel/locking/lockdep.c:5754 [inline]
                   lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
                   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
                   _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
                   rcutree_prepare_cpu+0x6c/0x590 kernel/rcu/tree.c:4484
                   rcu_init+0x15d0/0x20c0 kernel/rcu/tree.c:5224
                   start_kernel+0x19e/0x490 init/main.c:969
                   x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:509
                   x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:490
                   common_startup_64+0x13e/0x148
 }
 ... key      at: [<ffffffff94686cc0>] rcu_node_class.17+0x0/0x40

the dependencies between the lock to be acquired
 and HARDIRQ-irq-unsafe lock:
-> (&stab->lock){+...}-{2:2} {
   HARDIRQ-ON-W at:
                    lock_acquire kernel/locking/lockdep.c:5754 [inline]
                    lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
                    __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
                    _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178
                    spin_lock_bh include/linux/spinlock.h:356 [inline]
                    __sock_map_delete net/core/sock_map.c:414 [inline]
                    sock_map_delete_elem+0xc8/0x150 net/core/sock_map.c:446
                    ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
                    __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
                    bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
                    __bpf_prog_run include/linux/filter.h:657 [inline]
                    bpf_prog_run include/linux/filter.h:664 [inline]
                    __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
                    bpf_trace_run2+0x151/0x420 kernel/trace/bpf_trace.c:2420
                    __bpf_trace_contention_end+0xca/0x110 include/trace/events/lock.h:122
                    trace_contention_end+0xce/0x120 include/trace/events/lock.h:122
                    __mutex_lock_common kernel/locking/mutex.c:617 [inline]
                    __mutex_lock+0x19c/0x9c0 kernel/locking/mutex.c:752
                    futex_cleanup_begin kernel/futex/core.c:1091 [inline]
                    futex_exit_release+0x2a/0x220 kernel/futex/core.c:1143
                    exit_mm_release+0x19/0x30 kernel/fork.c:1652
                    exit_mm kernel/exit.c:542 [inline]
                    do_exit+0x865/0x2be0 kernel/exit.c:865
                    do_group_exit+0xd3/0x2a0 kernel/exit.c:1027
                    __do_sys_exit_group kernel/exit.c:1038 [inline]
                    __se_sys_exit_group kernel/exit.c:1036 [inline]
                    __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1036
                    do_syscall_x64 arch/x86/entry/common.c:52 [inline]
                    do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
                    entry_SYSCALL_64_after_hwframe+0x6d/0x75
   INITIAL USE at:
                   lock_acquire kernel/locking/lockdep.c:5754 [inline]
                   lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
                   __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
                   _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178
                   spin_lock_bh include/linux/spinlock.h:356 [inline]
                   __sock_map_delete net/core/sock_map.c:414 [inline]
                   sock_map_delete_elem+0xc8/0x150 net/core/sock_map.c:446
                   ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
                   __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
                   bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
                   __bpf_prog_run include/linux/filter.h:657 [inline]
                   bpf_prog_run include/linux/filter.h:664 [inline]
                   __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
                   bpf_trace_run2+0x151/0x420 kernel/trace/bpf_trace.c:2420
                   __bpf_trace_contention_end+0xca/0x110 include/trace/events/lock.h:122
                   trace_contention_end+0xce/0x120 include/trace/events/lock.h:122
                   __mutex_lock_common kernel/locking/mutex.c:617 [inline]
                   __mutex_lock+0x19c/0x9c0 kernel/locking/mutex.c:752
                   futex_cleanup_begin kernel/futex/core.c:1091 [inline]
                   futex_exit_release+0x2a/0x220 kernel/futex/core.c:1143
                   exit_mm_release+0x19/0x30 kernel/fork.c:1652
                   exit_mm kernel/exit.c:542 [inline]
                   do_exit+0x865/0x2be0 kernel/exit.c:865
                   do_group_exit+0xd3/0x2a0 kernel/exit.c:1027
                   __do_sys_exit_group kernel/exit.c:1038 [inline]
                   __se_sys_exit_group kernel/exit.c:1036 [inline]
                   __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1036
                   do_syscall_x64 arch/x86/entry/common.c:52 [inline]
                   do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
                   entry_SYSCALL_64_after_hwframe+0x6d/0x75
 }
 ... key      at: [<ffffffff949c6800>] __key.1+0x0/0x40
 ... acquired at:
   lock_acquire kernel/locking/lockdep.c:5754 [inline]
   lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
   __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
   _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178
   spin_lock_bh include/linux/spinlock.h:356 [inline]
   __sock_map_delete net/core/sock_map.c:414 [inline]
   sock_map_delete_elem+0xc8/0x150 net/core/sock_map.c:446
   ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
   __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
   bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
   __bpf_prog_run include/linux/filter.h:657 [inline]
   bpf_prog_run include/linux/filter.h:664 [inline]
   __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
   bpf_trace_run2+0x151/0x420 kernel/trace/bpf_trace.c:2420
   __bpf_trace_contention_end+0xca/0x110 include/trace/events/lock.h:122
   trace_contention_end.constprop.0+0xe2/0x140 include/trace/events/lock.h:122
   __pv_queued_spin_lock_slowpath+0x266/0xc80 kernel/locking/qspinlock.c:560
   pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
   queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
   queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
   do_raw_spin_lock+0x210/0x2c0 kernel/locking/spinlock_debug.c:116
   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
   _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162
   sync_rcu_exp_done_unlocked+0xc/0x90 kernel/rcu/tree_exp.h:169
   synchronize_rcu_expedited_wait_once kernel/rcu/tree_exp.h:516 [inline]
   synchronize_rcu_expedited_wait kernel/rcu/tree_exp.h:570 [inline]
   rcu_exp_wait_wake+0xee/0x15e0 kernel/rcu/tree_exp.h:641
   kthread_worker_fn+0x305/0xab0 kernel/kthread.c:841
   kthread+0x2c1/0x3a0 kernel/kthread.c:388
   ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
   ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243


stack backtrace:
CPU: 1 PID: 18 Comm: rcu_exp_gp_kthr Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline]
 check_irq_usage+0xe3c/0x1490 kernel/locking/lockdep.c:2865
 check_prev_add kernel/locking/lockdep.c:3138 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x248e/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x540 kernel/locking/lockdep.c:5719
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
 _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 __sock_map_delete net/core/sock_map.c:414 [inline]
 sock_map_delete_elem+0xc8/0x150 net/core/sock_map.c:446
 ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run2+0x151/0x420 kernel/trace/bpf_trace.c:2420
 __bpf_trace_contention_end+0xca/0x110 include/trace/events/lock.h:122
 trace_contention_end.constprop.0+0xe2/0x140 include/trace/events/lock.h:122
 __pv_queued_spin_lock_slowpath+0x266/0xc80 kernel/locking/qspinlock.c:560
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock+0x210/0x2c0 kernel/locking/spinlock_debug.c:116
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162
 sync_rcu_exp_done_unlocked+0xc/0x90 kernel/rcu/tree_exp.h:169
 synchronize_rcu_expedited_wait_once kernel/rcu/tree_exp.h:516 [inline]
 synchronize_rcu_expedited_wait kernel/rcu/tree_exp.h:570 [inline]
 rcu_exp_wait_wake+0xee/0x15e0 kernel/rcu/tree_exp.h:641
 kthread_worker_fn+0x305/0xab0 kernel/kthread.c:841
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

Crashes (30):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/12 04:30 upstream fe46a7dd189e 478efa7f .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root possible deadlock in rcu_report_exp_cpu_mult
2024/04/18 07:48 bpf 443574b03387 bd38b692 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/15 04:03 bpf 443574b03387 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/14 20:14 net f99c5f563c17 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/14 20:04 bpf 443574b03387 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/14 17:24 net f99c5f563c17 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/14 16:17 net f99c5f563c17 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/14 06:35 bpf 443574b03387 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/14 04:26 bpf 443574b03387 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/13 10:47 net f99c5f563c17 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/13 08:07 net f99c5f563c17 c8349e48 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/12 12:42 bpf 443574b03387 27de0a5c .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/12 11:05 bpf 443574b03387 27de0a5c .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/11 05:08 bpf 443574b03387 56086b24 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/11 04:43 bpf 443574b03387 56086b24 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/11 02:08 bpf 443574b03387 56086b24 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/07 18:44 bpf 443574b03387 ca620dd8 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/07 00:30 net f99c5f563c17 ca620dd8 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/03/16 22:51 net ea80e3ed09ab d615901c .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/03/24 03:19 net-next 237bb5f7f7f5 0ea90952 .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/03/16 22:12 bpf-next 4c8644f86c85 d615901c .config console log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/13 07:47 upstream fe46a7dd189e c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root possible deadlock in rcu_report_exp_cpu_mult
2024/04/25 10:45 bpf 443574b03387 8bdc0f22 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/24 12:00 bpf 443574b03387 21339d7b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/11 23:15 net f99c5f563c17 478efa7f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/10 12:42 bpf 443574b03387 56086b24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/10 03:17 net f99c5f563c17 56086b24 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/08 07:34 bpf-next 14bb1e8c8d4a ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/04/07 20:00 bpf-next 14bb1e8c8d4a ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
2024/03/27 03:46 bpf-next 14bb1e8c8d4a 454571b6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce possible deadlock in rcu_report_exp_cpu_mult
* Struck through repros no longer work on HEAD.