INFO: rcu detected stall in sys_mprotect (3)

Status: upstream: reported on 2025/09/19 07:33
Reported-by: syzbot+38389a646a23817e3097@syzkaller.appspotmail.com
First crash: 325d, last: 55d
▶ ▼ Similar bugs (17)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_mprotect (6) kernel 1 3 1306d 1357d 0/29 auto-obsoleted due to no activity on 2023/04/20 15:51
upstream INFO: rcu detected stall in sys_mprotect (3) mm 1 3 2406d 2406d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_mprotect (2) mm 1 1 2407d 2407d 0/29 closed as invalid on 2020/01/08 05:23
linux-6.6 INFO: rcu detected stall in sys_mprotect (2) origin:lts-only 1 syz error 6 25d 240d 0/2 upstream: reported syz repro on 2025/12/14 03:47
upstream INFO: rcu detected stall in sys_mprotect (8) prio:normal mm 1 syz done error 129 15h32m 668d 0/29 upstream: reported syz repro on 2024/10/11 07:05
linux-5.15 INFO: rcu detected stall in sys_mprotect 1 1 836d 836d 0/3 auto-obsoleted due to no activity on 2024/08/04 17:12
linux-6.6 INFO: rcu detected stall in sys_mprotect 1 1 361d 361d 0/2 auto-obsoleted due to no activity on 2025/11/23 01:57
upstream INFO: rcu detected stall in sys_mprotect (5) kernel 1 1 1625d 1625d 0/29 auto-closed as invalid on 2022/05/29 03:15
linux-5.15 INFO: rcu detected stall in sys_mprotect (4) 1 1 80d 80d 0/3 upstream: reported on 2026/05/22 15:45
linux-5.15 INFO: rcu detected stall in sys_mprotect (3) 1 1 286d 286d 0/3 auto-obsoleted due to no activity on 2026/02/05 12:28
upstream INFO: rcu detected stall in sys_mprotect (4) mm 1 1 1690d 1690d 0/29 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in sys_mprotect mm 1 3 2442d 2442d 0/29 closed as invalid on 2019/12/04 14:04
linux-5.15 INFO: rcu detected stall in sys_mprotect (2) 1 1 390d 390d 0/3 auto-obsoleted due to no activity on 2025/10/24 12:50
upstream INFO: rcu detected stall in sys_mprotect (7) mm 1 9 937d 1164d 0/29 auto-obsoleted due to no activity on 2024/04/15 19:55
linux-6.1 INFO: rcu detected stall in sys_mprotect (2) 1 1 561d 561d 0/3 auto-obsoleted due to no activity on 2025/05/06 08:25
linux-6.1 INFO: rcu detected stall in sys_mprotect 1 7 732d 808d 0/3 auto-obsoleted due to no activity on 2024/11/16 09:36
android-5-15 BUG: soft lockup in sys_mprotect 1 1 803d 803d 0/2 auto-obsoleted due to no activity on 2024/08/27 08:23

Sample crash report:
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2675 jiffies s: 293537 root: 0x1/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 21099 Comm: syz.3.13485 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4723 [inline]
RIP: 0010:__lock_acquire+0x549/0x7d10 kernel/locking/lockdep.c:4999
Code: 81 e3 ff 1f 00 00 41 c1 ed 03 41 81 e5 f8 03 00 00 49 8d bd 40 f2 af 90 be 08 00 00 00 e8 ef 39 6f 00 48 0f a3 1d 47 a7 4b 0f <73> 1f 48 8d 04 5b c1 e0 06 48 8d 98 00 71 48 90 48 ba 00 00 00 00
RSP: 0018:ffffc90000007080 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 000000000000002c RCX: ffffffff81644af1
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90aff240
RBP: ffffc900000072d0 R08: ffffffff90aff247 R09: 1ffffffff215fe48
R10: dffffc0000000000 R11: fffffbfff215fe49 R12: ffff888023abda00
R13: 0000000000000000 R14: 0000000000000000 R15: 000000000000002c
FS:  00005555936c3500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdb54e26d58 CR3: 0000000066851000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 trace_call_bpf+0xe0/0x6b0 kernel/trace/bpf_trace.c:134
 perf_trace_run_bpf_submit+0x79/0x1c0 kernel/events/core.c:10027
 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728
RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 82 30 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc90000007740 EFLAGS: 00000206
RAX: 876f43f42185e700 RBX: 1ffff92000000ef0 RCX: 876f43f42185e700
RDX: dffffc0000000000 RSI: ffffffff8a8c1aa0 RDI: ffffffff8adf2060
RBP: ffffc90000007828 R08: ffffffff90aff2ff R09: 1ffffffff215fe5f
R10: dffffc0000000000 R11: fffffbfff215fe60 R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 __ip_queue_xmit+0x1174/0x1c10 net/ipv4/ip_output.c:539
 __tcp_transmit_skb+0x1c9f/0x31b0 net/ipv4/tcp_output.c:1407
 tcp_delack_timer_handler+0x2a9/0x440 net/ipv4/tcp_timer.c:322
 tcp_delack_timer+0x188/0x2e0 net/ipv4/tcp_timer.c:345
 call_timer_fn+0x1ac/0x670 kernel/time/timer.c:1701
 expire_timers kernel/time/timer.c:1752 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:2023
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2036
 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
 __do_softirq kernel/softirq.c:630 [inline]
 invoke_softirq kernel/softirq.c:470 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 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:__orc_find arch/x86/kernel/unwind_orc.c:50 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x1340/0x20b0 arch/x86/kernel/unwind_orc.c:448
Code: 24 68 e8 75 f4 ea 08 e9 7f 05 00 00 49 89 f7 49 89 f5 4c 89 e0 4c 29 e8 48 89 c1 48 c1 f9 02 48 c1 e8 3f 48 01 c8 48 83 e0 fe <4d> 8d 74 45 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90005e9e730 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc90005e9e808 RCX: 0000000000000000
RDX: ffffffff8ea93d38 RSI: ffffffff8e364288 RDI: ffffffff81391adf
RBP: ffffffff81c29969 R08: 0000000000000001 R09: 0000000000000006
R10: dffffc0000000000 R11: fffff52000bd3d0d R12: ffffffff8e364288
R13: ffffffff8e364288 R14: 000000000000c299 R15: ffffffff8e364288
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486
 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849
 ma_free_rcu lib/maple_tree.c:184 [inline]
 mas_free lib/maple_tree.c:1343 [inline]
 mas_mat_free lib/maple_tree.c:1023 [inline]
 mas_wmb_replace+0xd77/0x13a0 lib/maple_tree.c:2813
 mas_split lib/maple_tree.c:3600 [inline]
 mas_commit_b_node lib/maple_tree.c:3651 [inline]
 mas_wr_bnode lib/maple_tree.c:4385 [inline]
 mas_wr_modify+0x3b4f/0x55c0 lib/maple_tree.c:4428
 mas_store_prealloc+0x2eb/0x440 lib/maple_tree.c:5790
 __vma_adjust+0x10ca/0x1cd0 mm/mmap.c:805
 vma_adjust include/linux/mm.h:2810 [inline]
 __split_vma+0x3a7/0x500 mm/mmap.c:-1
 mprotect_fixup+0x502/0x800 mm/mprotect.c:617
 do_mprotect_pkey+0x7fe/0xba0 mm/mprotect.c:792
 __do_sys_mprotect mm/mprotect.c:819 [inline]
 __se_sys_mprotect mm/mprotect.c:816 [inline]
 __x64_sys_mprotect+0x7c/0x90 mm/mprotect.c:816
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fdb53f9cc57
Code: 89 38 eb 84 0f 1f 80 00 00 00 00 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff e9 7a ff ff ff b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffe9d98b28 EFLAGS: 00000206 ORIG_RAX: 000000000000000a
RAX: ffffffffffffffda RBX: 00007fdb54e056c0 RCX: 00007fdb53f9cc57
RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007fdb54de6000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000021000 R11: 0000000000000206 R12: 00007fffe9d98c80
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
 </TASK>

Crashes (13):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/16 05:08 linux-6.1.y 228da13e907e 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_mprotect
2026/04/26 10:22 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2026/03/29 21:26 linux-6.1.y 1989cd3d56e2 b5ceaad2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2026/02/13 13:15 linux-6.1.y 8ce36b2849ef 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2026/02/01 15:01 linux-6.1.y cd9b81672742 6b8752f2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2026/01/27 20:57 linux-6.1.y cd9b81672742 9a514c2f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2026/01/25 09:09 linux-6.1.y cd9b81672742 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-perf INFO: rcu detected stall in sys_mprotect
2025/12/06 06:40 linux-6.1.y f6e38ae624cf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2025/10/17 18:09 linux-6.1.y c2fda4b3f577 7adf5298 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2025/10/12 23:57 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2025/09/30 14:18 linux-6.1.y 7b34dc04e4ff 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
2025/09/25 09:14 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 sys_mprotect
2025/09/19 07:32 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in sys_mprotect
* Struck through repros no longer work on HEAD.