syzbot


possible deadlock in __mod_timer (2)

Status: upstream: reported on 2024/08/11 05:04
Reported-by: syzbot+1e175fa5b198b9e3206f@syzkaller.appspotmail.com
First crash: 63d, last: 7d02h
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in __mod_timer (4) trace bpf C 4 10d 21d 0/28 upstream: reported C repro on 2024/09/22 06:39
upstream possible deadlock in __mod_timer kernel 35 672d 746d 0/28 auto-obsoleted due to no activity on 2023/04/09 11:04
linux-5.15 possible deadlock in __mod_timer 4 169d 187d 0/3 auto-obsoleted due to no activity on 2024/08/05 08:07
upstream possible deadlock in __mod_timer (2) kernel 1 522d 521d 22/28 fixed on 2023/07/01 16:05

Sample crash report:
------------[ cut here ]------------
======================================================
WARNING: possible circular locking dependency detected
5.15.167-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.28/3714 is trying to acquire lock:
ffffffff8c7fc4b8 ((console_sem).lock){..-.}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138

but task is already holding lock:
ffff8880b9028098 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x772/0xeb0 kernel/time/timer.c:1043

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&base->lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       lock_timer_base+0x120/0x260 kernel/time/timer.c:946
       __mod_timer+0x1d6/0xeb0 kernel/time/timer.c:1019
       queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1715
       psi_enqueue kernel/sched/stats.h:104 [inline]
       enqueue_task+0x2fe/0x3a0 kernel/sched/core.c:1970
       activate_task kernel/sched/core.c:2002 [inline]
       wake_up_new_task+0x515/0xb60 kernel/sched/core.c:4519
       kernel_clone+0x44e/0x960 kernel/fork.c:2628
       kernel_thread+0x168/0x1e0 kernel/fork.c:2656
       rest_init+0x21/0x330 init/main.c:706
       start_kernel+0x48c/0x540 init/main.c:1140
       secondary_startup_64_no_verify+0xb1/0xbb

-> #2 (&rq->__lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:368
       raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
       raw_spin_rq_lock kernel/sched/sched.h:1326 [inline]
       rq_lock kernel/sched/sched.h:1621 [inline]
       task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11484
       sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4463
       copy_process+0x224a/0x3ef0 kernel/fork.c:2320
       kernel_clone+0x210/0x960 kernel/fork.c:2604
       kernel_thread+0x168/0x1e0 kernel/fork.c:2656
       rest_init+0x21/0x330 init/main.c:706
       start_kernel+0x48c/0x540 init/main.c:1140
       secondary_startup_64_no_verify+0xb1/0xbb

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4027
       up+0x6e/0x90 kernel/locking/semaphore.c:190
       __up_console_sem+0x11a/0x1e0 kernel/printk/printk.c:256
       console_unlock+0x1145/0x12b0 kernel/printk/printk.c:2760
       vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
       _printk+0xd1/0x120 kernel/printk/printk.c:2299
       check_stack_usage kernel/exit.c:766 [inline]
       do_exit+0x1a91/0x2480 kernel/exit.c:917
       call_usermodehelper_exec_async+0x368/0x370 kernel/umh.c:125
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

-> #0 ((console_sem).lock){..-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
       down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138
       __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239
       console_trylock kernel/printk/printk.c:2575 [inline]
       console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867
       vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273
       _printk+0xd1/0x120 kernel/printk/printk.c:2299
       report_bug+0x1e5/0x2e0 lib/bug.c:195
       handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239
       exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:259
       asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:566
       copy_from_user_nofault+0x15c/0x1c0
       bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
       ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline]
       bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163
       bpf_prog_02073d59a3c0f06f+0x3d/0xa60
       bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
       __bpf_prog_run include/linux/filter.h:628 [inline]
       bpf_prog_run include/linux/filter.h:635 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
       bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
       trace_timer_start include/trace/events/timer.h:52 [inline]
       enqueue_timer+0x3ae/0x540 kernel/time/timer.c:586
       internal_add_timer kernel/time/timer.c:611 [inline]
       __mod_timer+0xa60/0xeb0 kernel/time/timer.c:1062
       queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1715
       queue_delayed_work include/linux/workqueue.h:527 [inline]
       srcu_funnel_gp_start kernel/rcu/srcutree.c:682 [inline]
       srcu_gp_start_if_needed+0x5dc/0x8f0 kernel/rcu/srcutree.c:838
       rcu_do_batch kernel/rcu/tree.c:2523 [inline]
       rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763
       handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
       __do_softirq kernel/softirq.c:592 [inline]
       invoke_softirq kernel/softirq.c:432 [inline]
       __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
       irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
       sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
       asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
       free_pages_and_swap_cache+0x49/0x90 mm/swap_state.c:319
       tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
       tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
       tlb_flush_mmu+0xc8/0x170 mm/mmu_gather.c:247
       zap_pte_range mm/memory.c:1445 [inline]
       zap_pmd_range mm/memory.c:1494 [inline]
       zap_pud_range mm/memory.c:1523 [inline]
       zap_p4d_range mm/memory.c:1544 [inline]
       unmap_page_range+0x214d/0x2630 mm/memory.c:1565
       unmap_vmas+0x1f8/0x390 mm/memory.c:1642
       exit_mmap+0x3b6/0x670 mm/mmap.c:3186
       __mmput+0x112/0x3b0 kernel/fork.c:1126
       exit_mm+0x688/0x7f0 kernel/exit.c:550
       do_exit+0x626/0x2480 kernel/exit.c:861
       do_group_exit+0x144/0x310 kernel/exit.c:996
       get_signal+0xc66/0x14e0 kernel/signal.c:2897
       arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
       handle_signal_work kernel/entry/common.c:154 [inline]
       exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
       exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
       __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
       syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
       do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &rq->__lock --> &base->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&base->lock);
                               lock(&rq->__lock);
                               lock(&base->lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

5 locks held by syz.0.28/3714:
 #0: ffffffff8c91fd20 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x0/0x20
 #1: ffffffff8c95f858 (tracepoint_srcu){....}-{0:0}, at: rcu_lock_acquire+0x0/0x20
 #2: ffffffff8c95f5d0 (tracepoint_srcu.lock){..-.}-{2:2}, at: srcu_funnel_gp_start kernel/rcu/srcutree.c:665 [inline]
 #2: ffffffff8c95f5d0 (tracepoint_srcu.lock){..-.}-{2:2}, at: srcu_gp_start_if_needed+0x460/0x8f0 kernel/rcu/srcutree.c:838
 #3: ffff8880b9028098 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x772/0xeb0 kernel/time/timer.c:1043
 #4: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 0 PID: 3714 Comm: syz.0.28 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138
 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239
 console_trylock kernel/printk/printk.c:2575 [inline]
 console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867
 vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 report_bug+0x1e5/0x2e0 lib/bug.c:195
 handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239
 exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:259
 asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:566
RIP: 0010:copy_from_user_nofault+0x15c/0x1c0 mm/maccess.c:226
Code: db 48 c7 c0 f2 ff ff ff 48 0f 44 c5 eb 0c e8 eb c6 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 d4 c6 d5 ff <0f> 0b e9 1e ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c ef fe ff
RSP: 0018:ffffc90000007760 EFLAGS: 00010046
RAX: ffffffff81aa939c RBX: 0000000000000000 RCX: ffff888020a59dc0
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff81aa92ad R09: fffffbfff20e2419
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: 0000000000000008 R14: 0000000000000000 R15: ffffc900000077c8
 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
 ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline]
 bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163
 bpf_prog_02073d59a3c0f06f+0x3d/0xa60
 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
 trace_timer_start include/trace/events/timer.h:52 [inline]
 enqueue_timer+0x3ae/0x540 kernel/time/timer.c:586
 internal_add_timer kernel/time/timer.c:611 [inline]
 __mod_timer+0xa60/0xeb0 kernel/time/timer.c:1062
 queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1715
 queue_delayed_work include/linux/workqueue.h:527 [inline]
 srcu_funnel_gp_start kernel/rcu/srcutree.c:682 [inline]
 srcu_gp_start_if_needed+0x5dc/0x8f0 kernel/rcu/srcutree.c:838
 rcu_do_batch kernel/rcu/tree.c:2523 [inline]
 rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:free_pages_and_swap_cache+0x49/0x90 mm/swap_state.c:319
Code: 31 be ff 45 85 f6 7e 4e 44 89 f0 4c 8d 3c c5 f8 ff ff ff 31 ed 49 bc 00 00 00 00 00 fc ff df 48 8d 3c 2b 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 7b f8 07 00 48 8b 3c 2b e8 b2 fa ff ff 49
RSP: 0018:ffffc900030e73b0 EFLAGS: 00000a02
RAX: 1ffff1100bda3bf8 RBX: ffff88805ed1d010 RCX: ffff888020a59dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805ed1dfc0
RBP: 0000000000000fb0 R08: ffffffff81c22820 R09: fffff940003c3e59
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88805ed1d008 R14: 00000000000001fc R15: 0000000000000fd8
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu+0xc8/0x170 mm/mmu_gather.c:247
 zap_pte_range mm/memory.c:1445 [inline]
 zap_pmd_range mm/memory.c:1494 [inline]
 zap_pud_range mm/memory.c:1523 [inline]
 zap_p4d_range mm/memory.c:1544 [inline]
 unmap_page_range+0x214d/0x2630 mm/memory.c:1565
 unmap_vmas+0x1f8/0x390 mm/memory.c:1642
 exit_mmap+0x3b6/0x670 mm/mmap.c:3186
 __mmput+0x112/0x3b0 kernel/fork.c:1126
 exit_mm+0x688/0x7f0 kernel/exit.c:550
 do_exit+0x626/0x2480 kernel/exit.c:861
 do_group_exit+0x144/0x310 kernel/exit.c:996
 get_signal+0xc66/0x14e0 kernel/signal.c:2897
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f16c5eb8ff9
Code: Unable to access opcode bytes at RIP 0x7f16c5eb8fcf.
RSP: 002b:00007f16c43310e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f16c6070f88 RCX: 00007f16c5eb8ff9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f16c6070f88
RBP: 00007f16c6070f80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f16c6070f8c
R13: 0000000000000000 R14: 00007ffd90ea9080 R15: 00007ffd90ea9168
 </TASK>
WARNING: CPU: 0 PID: 3714 at mm/maccess.c:226 copy_from_user_nofault+0x15c/0x1c0
Modules linked in:
CPU: 0 PID: 3714 Comm: syz.0.28 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:copy_from_user_nofault+0x15c/0x1c0 mm/maccess.c:226
Code: db 48 c7 c0 f2 ff ff ff 48 0f 44 c5 eb 0c e8 eb c6 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 d4 c6 d5 ff <0f> 0b e9 1e ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c ef fe ff
RSP: 0018:ffffc90000007760 EFLAGS: 00010046
RAX: ffffffff81aa939c RBX: 0000000000000000 RCX: ffff888020a59dc0
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff81aa92ad R09: fffffbfff20e2419
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: 0000000000000008 R14: 0000000000000000 R15: ffffc900000077c8
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32c1fffc CR3: 0000000065ffe000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline]
 ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline]
 bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163
 bpf_prog_02073d59a3c0f06f+0x3d/0xa60
 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
 bpf_trace_run3+0x1d1/0x380 kernel/trace/bpf_trace.c:1918
 trace_timer_start include/trace/events/timer.h:52 [inline]
 enqueue_timer+0x3ae/0x540 kernel/time/timer.c:586
 internal_add_timer kernel/time/timer.c:611 [inline]
 __mod_timer+0xa60/0xeb0 kernel/time/timer.c:1062
 queue_delayed_work_on+0x156/0x250 kernel/workqueue.c:1715
 queue_delayed_work include/linux/workqueue.h:527 [inline]
 srcu_funnel_gp_start kernel/rcu/srcutree.c:682 [inline]
 srcu_gp_start_if_needed+0x5dc/0x8f0 kernel/rcu/srcutree.c:838
 rcu_do_batch kernel/rcu/tree.c:2523 [inline]
 rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763
 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:free_pages_and_swap_cache+0x49/0x90 mm/swap_state.c:319
Code: 31 be ff 45 85 f6 7e 4e 44 89 f0 4c 8d 3c c5 f8 ff ff ff 31 ed 49 bc 00 00 00 00 00 fc ff df 48 8d 3c 2b 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 7b f8 07 00 48 8b 3c 2b e8 b2 fa ff ff 49
RSP: 0018:ffffc900030e73b0 EFLAGS: 00000a02
RAX: 1ffff1100bda3bf8 RBX: ffff88805ed1d010 RCX: ffff888020a59dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88805ed1dfc0
RBP: 0000000000000fb0 R08: ffffffff81c22820 R09: fffff940003c3e59
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff88805ed1d008 R14: 00000000000001fc R15: 0000000000000fd8
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu+0xc8/0x170 mm/mmu_gather.c:247
 zap_pte_range mm/memory.c:1445 [inline]
 zap_pmd_range mm/memory.c:1494 [inline]
 zap_pud_range mm/memory.c:1523 [inline]
 zap_p4d_range mm/memory.c:1544 [inline]
 unmap_page_range+0x214d/0x2630 mm/memory.c:1565
 unmap_vmas+0x1f8/0x390 mm/memory.c:1642
 exit_mmap+0x3b6/0x670 mm/mmap.c:3186
 __mmput+0x112/0x3b0 kernel/fork.c:1126
 exit_mm+0x688/0x7f0 kernel/exit.c:550
 do_exit+0x626/0x2480 kernel/exit.c:861
 do_group_exit+0x144/0x310 kernel/exit.c:996
 get_signal+0xc66/0x14e0 kernel/signal.c:2897
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f16c5eb8ff9
Code: Unable to access opcode bytes at RIP 0x7f16c5eb8fcf.
RSP: 002b:00007f16c43310e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f16c6070f88 RCX: 00007f16c5eb8ff9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f16c6070f88
RBP: 00007f16c6070f80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f16c6070f8c
R13: 0000000000000000 R14: 00007ffd90ea9080 R15: 00007ffd90ea9168
 </TASK>
----------------
Code disassembly (best guess):
   0:	31 be ff 45 85 f6    	xor    %edi,-0x97aba01(%rsi)
   6:	7e 4e                	jle    0x56
   8:	44 89 f0             	mov    %r14d,%eax
   b:	4c 8d 3c c5 f8 ff ff 	lea    -0x8(,%rax,8),%r15
  12:	ff
  13:	31 ed                	xor    %ebp,%ebp
  15:	49 bc 00 00 00 00 00 	movabs $0xdffffc0000000000,%r12
  1c:	fc ff df
  1f:	48 8d 3c 2b          	lea    (%rbx,%rbp,1),%rdi
  23:	48 89 f8             	mov    %rdi,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	74 05                	je     0x36
  31:	e8 7b f8 07 00       	call   0x7f8b1
  36:	48 8b 3c 2b          	mov    (%rbx,%rbp,1),%rdi
  3a:	e8 b2 fa ff ff       	call   0xfffffaf1
  3f:	49                   	rex.WB

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/06 08:10 linux-5.15.y 3a5928702e71 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf possible deadlock in __mod_timer
2024/08/11 05:03 linux-5.15.y 7e89efd3ae1c 6f4edef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in __mod_timer
* Struck through repros no longer work on HEAD.