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INFO: rcu detected stall in mas_find

Status: auto-obsoleted due to no activity on 2025/09/30 04:22
Subsystems: mm
[Documentation on labels]
First crash: 103d, last: 103d

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 ticks this GP) idle=07cc/1/0x4000000000000000 softirq=23541/23542 fqs=12
rcu: 	(detected by 0, t=10502 jiffies, g=14681, q=887 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7481 Comm: syz.0.435 Not tainted 6.16.0-rc3-syzkaller-00133-g42fd432fe6d3 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:kasan_check_range+0xb/0x2c0 mm/kasan/generic.c:188
Code: ff 90 0f 0b cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 55 <41> 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 f8 0f
RSP: 0018:ffffc90000a08bd8 EFLAGS: 00000082
RAX: ffffffff898655d4 RBX: 0000000000000000 RCX: ffffffff89865696
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff888058d59880
RBP: ffff888058d59880 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200014117c R12: 0000000000000000
R13: 000000007fffffff R14: ffff888058d59800 R15: ffff888058d59800
FS:  0000555581f65500(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f62b825ef40 CR3: 0000000062a6c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 atomic_set include/linux/atomic/atomic-instrumented.h:67 [inline]
 taprio_set_budgets+0x256/0x3b0 net/sched/sch_taprio.c:672
 advance_sched+0x963/0xc90 net/sched/sch_taprio.c:977
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:ma_dead_node lib/maple_tree.c:-1 [inline]
RIP: 0010:mas_rewalk_if_dead lib/maple_tree.c:4409 [inline]
RIP: 0010:mas_next_slot+0x9ca/0xcf0 lib/maple_tree.c:4744
Code: 85 db 0f 84 87 00 00 00 e8 83 a9 61 f6 eb 05 e8 7c a9 61 f6 4c 89 e8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ef e8 26 2d c5 f6 <49> 8b 45 00 48 c7 c1 00 ff ff ff 48 21 c8 49 39 c5 0f 84 ba 00 00
RSP: 0018:ffffc900056a7628 EFLAGS: 00000246
RAX: 1ffff1100c50e700 RBX: 0000000000000001 RCX: ffff888025da1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffff888025da1e00 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888062873800 R14: ffff8880313a4500 R15: ffffffffffffffff
 mas_find+0x9e7/0xc10 lib/maple_tree.c:6047
 vma_next include/linux/mm.h:864 [inline]
 vma_iter_next_rewind mm/vma.h:542 [inline]
 __mmap_prepare mm/vma.c:2361 [inline]
 __mmap_region mm/vma.c:2607 [inline]
 mmap_region+0x589/0x1f30 mm/vma.c:2692
 do_mmap+0xc45/0x10d0 mm/mmap.c:561
 vm_mmap_pgoff+0x31b/0x4c0 mm/util.c:579
 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:607
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62b838e963
Code: f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 41 89 ca 41 f7 c1 ff 0f 00 00 75 14 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 25 c3 0f 1f 40 00 48 c7 c0 a8 ff ff ff 64 c7
RSP: 002b:00007fffe7cb3ea8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000400000 RCX: 00007f62b838e963
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b2fc60000
RBP: 0000001b2fc60000 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000057
R13: 0000000000000060 R14: 000000000001ab4e R15: 00007fffe7cb4190
 </TASK>
rcu: rcu_preempt kthread starved for 10478 jiffies! g14681 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:27320 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 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: 5832 Comm: syz-executor Not tainted 6.16.0-rc3-syzkaller-00133-g42fd432fe6d3 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 c0 79 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 6b 75 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 50 75 0b
RSP: 0000:ffffc90003f8f720 EFLAGS: 00000293
RAX: ffffffff81b4d920 RBX: ffff8880b863b1c0 RCX: ffff888026f15a00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003f8f880 R08: ffffffff8fa10bf7 R09: 1ffffffff1f4217e
R10: dffffc0000000000 R11: fffffbfff1f4217f R12: 1ffff110170e7f5d
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b873fae8
FS:  00005555711dd500(0000) GS:ffff888125c50000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555711f85c8 CR3: 000000007866a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
 flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
 ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
 wp_page_copy mm/memory.c:3635 [inline]
 do_wp_page+0x1bc2/0x5800 mm/memory.c:4030
 handle_pte_fault mm/memory.c:6085 [inline]
 __handle_mm_fault+0x1144/0x5620 mm/memory.c:6212
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6381
 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f019a34cd9f
Code: 8d 34 19 48 39 d5 48 89 75 60 0f 95 c2 48 29 d8 48 83 c1 10 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 51 f8 <48> 89 46 08 eb 80 48 8d 0d 61 d3 0e 00 48 8d 15 65 e5 0e 00 bf 01
RSP: 002b:00007ffdd687adc0 EFLAGS: 00010206
RAX: 0000000000006a41 RBX: 0000000000008040 RCX: 00005555711f0590
RDX: 0000000000008041 RSI: 00005555711f85c0 RDI: 0000000000000004
RBP: 00007f019a584ca0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000802 R12: 0000000000008030
R13: 0000000000000076 R14: 00007f019a584d00 R15: 0000000000000000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/02 04:11 net 42fd432fe6d3 ffe4b334 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in mas_find
* Struck through repros no longer work on HEAD.