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INFO: rcu detected stall in vma_expand (2)

Status: auto-obsoleted due to no activity on 2024/11/09 10:52
Reported-by: syzbot+39c1e917d175ca1386ef@syzkaller.appspotmail.com
First crash: 691d, last: 691d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: rcu detected stall in vma_expand origin:lts-only 1 syz error 1 43d 43d 0/2 upstream: reported syz repro on 2026/05/10 14:35
linux-6.1 INFO: rcu detected stall in vma_expand 1 1 929d 929d 0/3 auto-obsoleted due to no activity on 2024/03/15 20:47
upstream INFO: rcu detected stall in vma_expand mm 1 8 662d 778d 0/29 auto-obsoleted due to no activity on 2024/11/27 12:01
linux-6.1 INFO: rcu detected stall in vma_expand (3) 1 4 147d 327d 0/3 auto-obsoleted due to no activity on 2026/05/06 20:38

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3939/1:b..l P3955/1:b..l
	(detected by 1, t=10502 jiffies, g=7617, q=93 ncpus=2)
task:syz-executor    state:R  running task     stack:27080 pid:3955  ppid:3634   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__kasan_check_write+0x0/0x10 mm/kasan/shadow.c:37
Code: 8e b7 8c eb 0a 48 c7 c7 dd 8e b7 8c 4c 89 fe e8 16 b2 c0 08 31 db eb d7 cc cc 89 f6 48 8b 0c 24 31 d2 e9 d3 ec ff ff 0f 1f 00 <89> f6 48 8b 0c 24 ba 01 00 00 00 e9 c0 ec ff ff 55 41 56 53 48 89
RSP: 0018:ffffc90004b17558 EFLAGS: 00000207
RAX: ffffffff8a9bea01 RBX: dffffc0000000000 RCX: ffffffff8a9beac4
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff923a1d60
RBP: ffffc90004b17750 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffff92000962ecb
R13: ffffc90004b17658 R14: ffff8880744d2580 R15: ffff8880177affd8
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_inc include/linux/atomic/atomic-instrumented.h:190 [inline]
 mt_validate_nulls lib/maple_tree.c:7192 [inline]
 mt_validate+0x50dc/0x5ad0 lib/maple_tree.c:7243
 validate_mm_mt+0x165/0x670 mm/mmap.c:295
 validate_mm+0x16e/0x380 mm/mmap.c:332
 vma_expand+0x87e/0x8f0 mm/mmap.c:604
 mmap_region+0xc3f/0x1fa0 mm/mmap.c:2730
 do_mmap+0x8c5/0xf60 mm/mmap.c:1425
 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:520
 ksys_mmap_pgoff+0x4f5/0x6d0 mm/mmap.c:1471
 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: 0033:0x7f70f0d773f3
RSP: 002b:00007fffbf7ca9f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000000000400000 RCX: 00007f70f0d773f3
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b2e960000
RBP: 0000001b2e960000 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000032
R13: 0000000000014753 R14: 00000000000143c4 R15: 00007fffbf7cacd0
 </TASK>
task:syz.2.60        state:R  running task     stack:25896 pid:3939  ppid:3647   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:658
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:lock_acquire+0xf3/0x5a0 kernel/locking/lockdep.c:5633
Code: 0d 0f 86 e4 02 00 00 89 db 48 89 d8 48 c1 e8 06 48 8d 3c c5 68 bd 99 8e be 08 00 00 00 e8 35 b8 77 00 48 0f a3 1d 85 50 2f 0d <73> 0d e8 66 e5 08 00 84 c0 0f 84 b9 02 00 00 48 c7 c0 24 f2 99 8e
RSP: 0018:ffffc900049975a0 EFLAGS: 00000257
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff816a6cdb
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8e99bd68
RBP: ffffc900049976f0 R08: dffffc0000000000 R09: fffffbfff1d337ae
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000932ebc
R13: dffffc0000000000 R14: 0000000000000000 R15: 00007f2f9e576fbb
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 is_bpf_text_address+0x3e/0x2a0 kernel/bpf/core.c:731
 kernel_text_address+0x9f/0xd0 kernel/extable.c:125
 __kernel_text_address+0x9/0x40 kernel/extable.c:79
 unwind_get_return_address+0x49/0x80 arch/x86/kernel/unwind_orc.c:323
 arch_stack_walk+0xf3/0x140 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 raw_ioctl+0x2235/0x3bf0
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 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: 0033:0x7f2f9e576fbb
RSP: 002b:00007f2f9f2acf20 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f2f9e576fbb
RDX: 00007f2f9f2acfe0 RSI: 0000000040085503 RDI: 0000000000000009
RBP: 00007f2f9f2adff0 R08: 0000000000000080 R09: 00007f2f9f2acfe8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 0000000000000012 R15: 00007f2f9e5edee8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10581 jiffies! g7617 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=4822
rcu: rcu_preempt kthread starved for 10582 jiffies! g7617 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:27064 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:567
sched: RT throttling activated

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/01 10:51 linux-6.1.y c1cec4dad96b 1e9c4cf3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in vma_expand
* Struck through repros no longer work on HEAD.