Subject: [syzbot] [kernel?] BUG: using smp_processor_id() in preemptible code in pwq_release_workfn

From: syzbot <[email-masked]>
Date: Wed, 27 Mar 2024 18:37:17 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    61df575632d6 libbpf: Add new sec_def "sk_skb/verdict"
git tree:       bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17683185180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6fb1be60a193d440
dashboard link: https://syzkaller.appspot.com/bug?extid=60f75ab7624f6e44392b
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0d2d0f91bfad/disk-61df5756.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0b0f2fd80260/vmlinux-61df5756.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0450c835a85f/bzImage-61df5756.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

BUG: using smp_processor_id() in preemptible [00000000] code: pool_workqueue_/3
caller is pv_init_node kernel/locking/qspinlock_paravirt.h:284 [inline]
caller is __pv_queued_spin_lock_slowpath+0x192/0xc60 kernel/locking/qspinlock.c:439
CPU: 1 PID: 3 Comm: pool_workqueue_ Not tainted 6.8.0-syzkaller-05238-g61df575632d6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 check_preemption_disabled+0x10e/0x120 lib/smp_processor_id.c:49
 pv_init_node kernel/locking/qspinlock_paravirt.h:284 [inline]
 __pv_queued_spin_lock_slowpath+0x192/0xc60 kernel/locking/qspinlock.c:439
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
 queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 lockdep_lock+0x1b0/0x2b0 kernel/locking/lockdep.c:144
 lockdep_unregister_key+0x20d/0x540 kernel/locking/lockdep.c:6456
 wq_unregister_lockdep kernel/workqueue.c:4655 [inline]
 pwq_release_workfn+0x6e0/0x840 kernel/workqueue.c:4958
 kthread_worker_fn+0x4bf/0xab0 kernel/kthread.c:841
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
BUG: using __this_cpu_add() in preemptible [00000000] code: pool_workqueue_/3
caller is __pv_queued_spin_lock_slowpath+0x945/0xc60 kernel/locking/qspinlock.c:565
CPU: 1 PID: 3 Comm: pool_workqueue_ Not tainted 6.8.0-syzkaller-05238-g61df575632d6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 check_preemption_disabled+0x10e/0x120 lib/smp_processor_id.c:49
 __pv_queued_spin_lock_slowpath+0x945/0xc60 kernel/locking/qspinlock.c:565
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
 queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 lockdep_lock+0x1b0/0x2b0 kernel/locking/lockdep.c:144
 lockdep_unregister_key+0x20d/0x540 kernel/locking/lockdep.c:6456
 wq_unregister_lockdep kernel/workqueue.c:4655 [inline]
 pwq_release_workfn+0x6e0/0x840 kernel/workqueue.c:4958
 kthread_worker_fn+0x4bf/0xab0 kernel/kthread.c:841
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
BUG: using __this_cpu_add() in preemptible [00000000] code: pool_workqueue_/3
caller is lockdep_unlock+0x16a/0x300 kernel/locking/lockdep.c:157
CPU: 1 PID: 3 Comm: pool_workqueue_ Not tainted 6.8.0-syzkaller-05238-g61df575632d6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 check_preemption_disabled+0x10e/0x120 lib/smp_processor_id.c:49
 lockdep_unlock+0x16a/0x300 kernel/locking/lockdep.c:157
 lockdep_unregister_key+0x45c/0x540 kernel/locking/lockdep.c:6471
 wq_unregister_lockdep kernel/workqueue.c:4655 [inline]
 pwq_release_workfn+0x6e0/0x840 kernel/workqueue.c:4958
 kthread_worker_fn+0x4bf/0xab0 kernel/kthread.c:841
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243
 </TASK>

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