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INFO: rcu detected stall in mas_store_prealloc (3)

Status: auto-obsoleted due to no activity on 2025/09/03 06:15
Subsystems: mm
[Documentation on labels]
First crash: 273d, last: 273d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mas_store_prealloc (2) mm 1 2 497d 504d 0/29 auto-obsoleted due to no activity on 2025/01/22 20:20
upstream INFO: rcu detected stall in mas_store_prealloc (4) mm 1 1 161d 161d 0/29 auto-obsoleted due to no activity on 2025/12/24 05:56
upstream INFO: rcu detected stall in mas_store_prealloc mm 1 1 964d 964d 0/29 auto-obsoleted due to no activity on 2023/10/13 16:47
linux-6.1 INFO: rcu detected stall in mas_store_prealloc 1 1 621d 621d 0/3 auto-obsoleted due to no activity on 2024/09/30 04:09

Sample crash report:
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P14236/1:b..l P23546/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=71573, q=784 ncpus=2)
task:modprobe        state:R  running task     stack:26696 pid:23546 tgid:23546 ppid:1162   task_flags:0x400000 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6785
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7108
 irqentry_exit+0x36/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:842 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
RIP: 0010:unwind_next_frame+0xa36/0x20a0 arch/x86/kernel/unwind_orc.c:479
Code: 87 0c 00 0f 84 6d f9 ff ff 80 3d 74 f0 67 12 00 0f 85 60 f9 ff ff 4c 89 ef c6 05 64 f0 67 12 01 e8 cf f0 ff ff e9 4c f9 ff ff <e8> c5 8b 36 00 84 c0 0f 85 9c f6 ff ff e8 98 3f 14 0a 85 c0 0f 84
RSP: 0018:ffffc9000356ecf8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 00000000f15b9e87
RDX: ffffffff816ac8ad RSI: ffffffff8ddef7a3 RDI: ffffffff8c157060
RBP: ffffc9000356edb0 R08: 6616c1856c1cfbea R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffffffff81a77a90
R13: ffffc9000356ed68 R14: 0000000000000000 R15: ffff88802677c880
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xa7/0xc0 mm/kasan/generic.c:548
 __call_rcu_common.constprop.0+0x9a/0x9f0 kernel/rcu/tree.c:3090
 mas_free lib/maple_tree.c:1313 [inline]
 mas_replace_node lib/maple_tree.c:1752 [inline]
 mas_wr_node_store+0xdc8/0x1620 lib/maple_tree.c:3887
 mas_wr_store_entry+0x102d/0x2550 lib/maple_tree.c:4098
 mas_store_prealloc+0x771/0x1680 lib/maple_tree.c:5506
 vma_iter_store_new mm/vma.h:455 [inline]
 __mmap_new_vma mm/vma.c:2476 [inline]
 __mmap_region+0x1639/0x25e0 mm/vma.c:2615
 mmap_region+0x1ab/0x3f0 mm/vma.c:2685
 do_mmap+0xa3e/0x1210 mm/mmap.c:561
 vm_mmap_pgoff+0x281/0x450 mm/util.c:579
 vm_mmap+0x8e/0xc0 mm/util.c:615
 elf_map fs/binfmt_elf.c:384 [inline]
 elf_load+0x36d/0x780 fs/binfmt_elf.c:407
 load_elf_binary+0x13c8/0x4f00 fs/binfmt_elf.c:1173
 search_binary_handler fs/exec.c:1665 [inline]
 exec_binprm fs/exec.c:1697 [inline]
 bprm_execve fs/exec.c:1749 [inline]
 bprm_execve+0x8c3/0x1650 fs/exec.c:1725
 kernel_execve+0x2ef/0x3b0 fs/exec.c:1915
 call_usermodehelper_exec_async+0x255/0x4c0 kernel/umh.c:109
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
task:kworker/u8:3    state:R  running task     stack:22584 pid:14236 tgid:14236 ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6785
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7108
 irqentry_exit+0x36/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875
Code: e2 33 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 42 81 0f 0f 0f 82 74 02 00 00 8b 35 2a b3 0f 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 d9 e1 33 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc90003ddfa68 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c4cc0 RCX: 0000000068c9ccde
RDX: 0000000000000000 RSI: ffffffff8ddef7a3 RDI: ffffffff8c157060
RBP: 0000000000000002 R08: fb723964e4088d99 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:762 [inline]
 batadv_iv_ogm_schedule_buff+0x5b4/0x14e0 net/batman-adv/bat_iv_ogm.c:833
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:876 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:869 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x329/0x920 net/batman-adv/bat_iv_ogm.c:1720
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread starved for 9745 jiffies! g71573 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:27784 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x116a/0x5de0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6878
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256
 kthread+0x3c5/0x780 kernel/kthread.c:464
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.15.0-syzkaller-12058-g64980441d269 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: 1b 73 02 e9 03 fb 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 f0 2a 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e207e08 EFLAGS: 000002c6
RAX: 0000000009670123 RBX: 0000000000000000 RCX: ffffffff8b7f1c99
RDX: 0000000000000000 RSI: ffffffff8de14d4b RDI: ffffffff8c157060
RBP: fffffbfff1c52ef0 R08: 0000000000000001 R09: ffffed1017086645
R10: ffff8880b843322b R11: 0000000000000001 R12: 0000000000000000
R13: ffffffff8e297780 R14: ffffffff90a7ff50 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88812475a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd588d36f98 CR3: 0000000035930000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:743
 default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
 cpuidle_idle_call kernel/sched/idle.c:185 [inline]
 do_idle+0x391/0x510 kernel/sched/idle.c:325
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
 rest_init+0x16b/0x2b0 init/main.c:744
 start_kernel+0x3ee/0x4d0 init/main.c:1101
 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:307
 x86_64_start_kernel+0x130/0x190 arch/x86/kernel/head64.c:288
 common_startup_64+0x13e/0x148
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/05 06:06 upstream 64980441d269 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in mas_store_prealloc
* Struck through repros no longer work on HEAD.