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INFO: rcu detected stall in sys_munmap (2)

Status: upstream: reported on 2025/04/02 07:15
Reported-by: syzbot+87c23d2143b7fa642291@syzkaller.appspotmail.com
First crash: 2d14h, last: 2d14h
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_munmap kasan mm 1 575d 575d 0/28 auto-obsoleted due to no activity on 2023/11/06 05:09
linux-6.1 INFO: rcu detected stall in sys_munmap 1 255d 255d 0/3 auto-obsoleted due to no activity on 2024/10/31 01:03

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=03fc/1/0x4000000000000000 softirq=19694/19694 fqs=0
	(detected by 1, t=10502 jiffies, g=26477, q=100 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6817 Comm: syz.3.855 Not tainted 6.1.132-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:-1 [inline]
RIP: 0010:rcu_is_watching+0x40/0xb0 kernel/rcu/tree.c:721
Code: 73 76 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 70 69 df 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 30 74 6e 00 <48> c7 c3 a8 56 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38
RSP: 0018:ffffc90000007b20 EFLAGS: 00000046
RAX: 1ffffffff19bed2e RBX: 0000000000000000 RCX: ffffffff816ab57b
RDX: 0000000000000000 RSI: ffffffff8b5f70c0 RDI: ffffffff8b5f7080
RBP: ffffc90000007c98 R08: dffffc0000000000 R09: fffffbfff1d416c6
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000000f70
R13: dffffc0000000000 R14: ffffffff8cdf6970 R15: dffffc0000000000
FS:  00007fc56c4976c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d61bff8 CR3: 000000007dcad000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xfa/0x5a0 kernel/locking/lockdep.c:5633
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0x47/0x970 net/sched/sch_taprio.c:700
 __run_hrtimer kernel/time/hrtimer.c:1691 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline]
RIP: 0010:lock_release+0x172/0xa20 kernel/locking/lockdep.c:5678
Code: 00 00 00 4c 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bf 2f 77 00 4c 89 6c 24 48 48 c7 84 24 b0 00 00 00 00 00 00 00 <9c> 8f 84 24 b0 00 00 00 42 80 3c 3b 00 74 08 4c 89 f7 e8 17 2f 77
RSP: 0018:ffffc90005ce7420 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff92000b9ce9a RCX: ffffffff816adbb7
RDX: 0000000000000000 RSI: ffffffff8b5f70c0 RDI: ffffffff8b5f7080
RBP: ffffc90005ce7558 R08: dffffc0000000000 R09: fffffbfff1d416c6
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000b9ce90
R13: ffffffff81ece856 R14: ffffc90005ce74d0 R15: dffffc0000000000
 rcu_lock_release include/linux/rcupdate.h:355 [inline]
 rcu_read_unlock_sched include/linux/rcupdate.h:904 [inline]
 pfn_valid+0x3eb/0x440 include/linux/mmzone.h:1867
 page_table_check_clear+0x1e/0x6d0 mm/page_table_check.c:67
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 zap_pte_range mm/memory.c:1435 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x1b4a/0x2740 mm/memory.c:1645
 unmap_vmas+0x48b/0x640 mm/memory.c:1730
 unmap_region+0x1fc/0x2f0 mm/mmap.c:2328
 do_mas_align_munmap+0xef5/0x15a0 mm/mmap.c:2580
 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2638
 __vm_munmap+0x268/0x370 mm/mmap.c:2924
 __do_sys_munmap mm/mmap.c:2949 [inline]
 __se_sys_munmap mm/mmap.c:2946 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2946
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc56b58d1f7
Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc56c496e18 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fc56b58d1f7
RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007fc560df7000
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000988f
R10: 0000200000009842 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fc56c496ef0 R14: 00007fc56c496eb0 R15: 00007fc560df7000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g26477 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=9810
rcu: rcu_preempt kthread starved for 10502 jiffies! g26477 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:26080 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6817 Comm: syz.3.855 Not tainted 6.1.132-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:kasan_check_range+0x1ae/0x290 mm/kasan/generic.c:189
Code: d5 48 8d 5d 07 48 85 ed 48 0f 49 dd 48 83 e3 f8 48 29 dd 74 12 41 80 39 00 0f 85 a2 00 00 00 49 ff c1 48 ff cd 75 ee 5b 41 5e <41> 5f 5d c3 45 84 f6 75 61 41 f7 c6 00 ff 00 00 75 5d 41 f7 c6 00
RSP: 0018:ffffc900000079e8 EFLAGS: 00000056
RAX: 0000000000000001 RBX: 000000000000005e RCX: ffffffff816acae7
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff912bb268
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff225764e
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88802d026418
R13: ffff88802d025940 R14: 0000000000000000 R15: 1ffff11005a04c9c
FS:  00007fc56c4976c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d61bff8 CR3: 000000007dcad000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 __lock_acquire+0xf77/0x1f80 kernel/locking/lockdep.c:5045
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_deactivate+0x63/0x380 lib/debugobjects.c:753
 debug_hrtimer_deactivate kernel/time/hrtimer.c:416 [inline]
 debug_deactivate+0x1d/0x280 kernel/time/hrtimer.c:472
 __run_hrtimer kernel/time/hrtimer.c:1659 [inline]
 __hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1755
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1817
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline]
RIP: 0010:lock_release+0x172/0xa20 kernel/locking/lockdep.c:5678
Code: 00 00 00 4c 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bf 2f 77 00 4c 89 6c 24 48 48 c7 84 24 b0 00 00 00 00 00 00 00 <9c> 8f 84 24 b0 00 00 00 42 80 3c 3b 00 74 08 4c 89 f7 e8 17 2f 77
RSP: 0018:ffffc90005ce7420 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 1ffff92000b9ce9a RCX: ffffffff816adbb7
RDX: 0000000000000000 RSI: ffffffff8b5f70c0 RDI: ffffffff8b5f7080
RBP: ffffc90005ce7558 R08: dffffc0000000000 R09: fffffbfff1d416c6
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000b9ce90
R13: ffffffff81ece856 R14: ffffc90005ce74d0 R15: dffffc0000000000
 rcu_lock_release include/linux/rcupdate.h:355 [inline]
 rcu_read_unlock_sched include/linux/rcupdate.h:904 [inline]
 pfn_valid+0x3eb/0x440 include/linux/mmzone.h:1867
 page_table_check_clear+0x1e/0x6d0 mm/page_table_check.c:67
 ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
 zap_pte_range mm/memory.c:1435 [inline]
 zap_pmd_range mm/memory.c:1574 [inline]
 zap_pud_range mm/memory.c:1603 [inline]
 zap_p4d_range mm/memory.c:1624 [inline]
 unmap_page_range+0x1b4a/0x2740 mm/memory.c:1645
 unmap_vmas+0x48b/0x640 mm/memory.c:1730
 unmap_region+0x1fc/0x2f0 mm/mmap.c:2328
 do_mas_align_munmap+0xef5/0x15a0 mm/mmap.c:2580
 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2638
 __vm_munmap+0x268/0x370 mm/mmap.c:2924
 __do_sys_munmap mm/mmap.c:2949 [inline]
 __se_sys_munmap mm/mmap.c:2946 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2946
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc56b58d1f7
Code: 00 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc56c496e18 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fc56b58d1f7
RDX: 0000000000000000 RSI: 0000000008400000 RDI: 00007fc560df7000
RBP: 0000000000000000 R08: 0000000000000000 R09: 000000000000988f
R10: 0000200000009842 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fc56c496ef0 R14: 00007fc56c496eb0 R15: 00007fc560df7000
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/02 07:16 linux-6.1.y 8e60a714ba3b c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_munmap
2025/04/02 07:14 linux-6.1.y 8e60a714ba3b c799dfdd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_munmap
* Struck through repros no longer work on HEAD.