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INFO: rcu detected stall in do_mas_munmap (2)

Status: upstream: reported on 2025/03/26 06:55
Reported-by: syzbot+009b2a7f9d8a0615cf9b@syzkaller.appspotmail.com
First crash: 214d, last: 7d00h
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in do_mas_munmap 1 12 383d 505d 0/3 auto-obsoleted due to no activity on 2025/01/16 11:56
upstream INFO: rcu detected stall in do_mas_munmap kernel 1 3 1001d 1063d 0/29 auto-obsoleted due to no activity on 2023/04/29 23:21

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10457/1:b..l
	(detected by 1, t=10503 jiffies, g=53645, q=55 ncpus=2)
task:modprobe        state:R  running task     stack:24352 pid:10457 ppid:4651   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5710
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90005fcf378 EFLAGS: 00000206
RAX: a992940a63c24300 RBX: ffff88802d8cbb80 RCX: a992940a63c24300
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef3a0
RBP: 0000000000000001 R08: dffffc0000000000 R09: ffffc90005fcf4b0
R10: fffff52000bf9e98 R11: 1ffff92000bf9e96 R12: 0000000000000000
R13: 0000000000000246 R14: ffff88807f0788d8 R15: ffff88802d8cc660
 lock_is_held include/linux/lockdep.h:283 [inline]
 mt_locked lib/maple_tree.c:-1 [inline]
 mas_root lib/maple_tree.c:858 [inline]
 mas_start lib/maple_tree.c:1399 [inline]
 mt_validate_nulls lib/maple_tree.c:7182 [inline]
 mt_validate+0x3f8c/0x4c90 lib/maple_tree.c:7247
 validate_mm_mt+0xcd/0x420 mm/mmap.c:295
 validate_mm+0xcc/0x2b0 mm/mmap.c:332
 remove_mt mm/mmap.c:2322 [inline]
 do_mas_align_munmap+0xf98/0x1220 mm/mmap.c:2595
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650
 __mmap_region mm/mmap.c:2698 [inline]
 mmap_region+0x6e5/0x1c70 mm/mmap.c:2916
 do_mmap+0x958/0xfd0 mm/mmap.c:1436
 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520
 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f23f14ac242
RSP: 002b:00007ffec3f19958 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f23f120e000 RCX: 00007f23f14ac242
RDX: 0000000000000005 RSI: 000000000014e000 RDI: 00007f23f120e000
RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000028000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffec3f199a8
R13: 00007f23f14885f0 R14: 00007ffec3f1a190 R15: 00000fffd87e332e
 </TASK>
rcu: rcu_preempt kthread starved for 10538 jiffies! g53645 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27744 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
 try_to_del_timer_sync+0x165/0x1b0 kernel/time/timer.c:1318
 timer_delete_sync+0x1de/0x2a0 kernel/time/timer.c:1466
 del_timer_sync include/linux/timer.h:198 [inline]
 schedule_timeout+0x164/0x280 kernel/time/timer.c:1966
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 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: 10460 Comm: syz.6.1416 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:asm_sysvec_irq_work+0x3/0x20 arch/x86/include/asm/idtentry.h:728
Code: 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 b5 02 00 00 48 89 c4 48 89 e7 e8 1a 8d d7 ff e9 95 03 00 00 90 90 90 90 90 0f 01 ca <fc> 6a ff e8 95 02 00 00 48 89 c4 48 89 e7 e8 ea 91 d7 ff e9 75 03
RSP: 0018:ffffc9000c2b7c88 EFLAGS: 00000046
RAX: 00000000000000f6 RBX: ffffffff8c5e4b88 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffff52001856f85
R10: fffff52001856f85 R11: 1ffff92001856f84 R12: ffff8880b8e33e01
R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020
FS:  00007f30bd43f6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f30bc7e6098 CR3: 000000007ceee000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:207 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:147 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:254 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:206
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 5f e0 f7 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc9000c2b7cb0 EFLAGS: 00000246
 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31
 irq_work_queue+0x95/0x140 kernel/irq_work.c:114
 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:879
 ____bpf_send_signal kernel/trace/bpf_trace.c:888 [inline]
 bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:886
 bpf_prog_7ba5217f62dcd359+0x38/0x3c
 bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2285 [inline]
 bpf_trace_run2+0x1cd/0x3b0 kernel/trace/bpf_trace.c:2324
 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
 trace_sys_enter+0x6b/0x80 include/trace/events/syscalls.h:18
 syscall_trace_enter+0xf0/0x150 kernel/entry/common.c:81
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:77
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f30bc52b099
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007f30bd43eb40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f30bc7e6098 RCX: 00007f30bc52b099
RDX: 00007f30bd43eb40 RSI: 00007f30bd43ec70 RDI: 0000000000000011
RBP: 00007f30bc7e6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f30bc7e6128 R14: 00007fff4c9f4780 R15: 00007fff4c9f4868
 </TASK>

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/20 01:49 linux-6.1.y 8e6e2188d949 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/09/25 04:04 linux-6.1.y 363a599da6d9 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/09/10 15:40 linux-6.1.y f97f1002271b fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/08/14 01:16 linux-6.1.y 3594f306da12 22ec1469 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/07/17 07:20 linux-6.1.y f2198ea7eb3e 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/07/13 22:44 linux-6.1.y dfc486ec9cce 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/06/23 10:14 linux-6.1.y 58485ff1a74f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/06/15 01:20 linux-6.1.y 58485ff1a74f 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/06/04 18:46 linux-6.1.y 58485ff1a74f e565f08d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
2025/03/26 06:54 linux-6.1.y 344a09659766 89d30d73 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in do_mas_munmap
* Struck through repros no longer work on HEAD.