[syzbot] [mm?] INFO: rcu detected stall in vms_gather_munmap_vmas

[syzbot] [mm?] INFO: rcu detected stall in vms_gather_munmap_vmas

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    82f2b0b97b36 Linux 6.15-rc6
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=129f4cd4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=714342dbe6af3a03
dashboard link: https://syzkaller.appspot.com/bug?extid=701fc0fcde2b68c4bf59
compiler:       Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7a2b57ba9ad2/disk-82f2b0b9.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2dabda38719c/vmlinux-82f2b0b9.xz
kernel image: https://storage.googleapis.com/syzbot-assets/5e734acfa53b/bzImage-82f2b0b9.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+701fc0fcde2b68c4bf59@syzkaller.appspotmail.com

bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5179/1:b..l P7230/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=21217, q=525 ncpus=2)
task:sed             state:R  running task     stack:24280 pid:7230  tgid:7230  ppid:7226   task_flags:0x400000 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5870
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 6b 32 d4 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90003656f70 EFLAGS: 00000206
RAX: 983870c225f6e200 RBX: 0000000000000000 RCX: 983870c225f6e200
RDX: 0000000000000000 RSI: ffffffff8d9219f6 RDI: ffffffff8bc0ffa0
RBP: ffffffff822a7ffa R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff822a7ffa R12: 0000000000000002
R13: ffffffff8df3d860 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 __page_table_check_zero+0xd7/0x510 mm/page_table_check.c:138
 page_table_check_free include/linux/page_table_check.h:41 [inline]
 free_pages_prepare mm/page_alloc.c:1263 [inline]
 __free_frozen_pages+0xb19/0xcd0 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4203
 mt_alloc_one lib/maple_tree.c:176 [inline]
 mas_alloc_nodes+0x2e9/0x8e0 lib/maple_tree.c:1249
 mas_node_count_gfp lib/maple_tree.c:1331 [inline]
 mas_preallocate+0x542/0x8b0 lib/maple_tree.c:5501
 vma_iter_prealloc mm/vma.h:409 [inline]
 __split_vma+0x315/0x9b0 mm/vma.c:490
 vms_gather_munmap_vmas+0x4ab/0x12b0 mm/vma.c:1336
 __mmap_prepare mm/vma.c:2303 [inline]
 __mmap_region mm/vma.c:2506 [inline]
 mmap_region+0x5f5/0x1e50 mm/vma.c:2597
 do_mmap+0xc68/0x1100 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+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f60fe10d242
RSP: 002b:00007fff93f23708 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f60fdde1000 RCX: 00007f60fe10d242
RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007f60fdde1000
RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000006000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007fff93f237c8
R13: 00007f60fdde40c0 R14: 00007fff93f23b40 R15: 00000ffff27e46e4
 </TASK>
task:klogd           state:R  running task     stack:24280 pid:5179  tgid:5179  ppid:1      task_flags:0x400100 flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x168f/0x4c70 kernel/sched/core.c:6767
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7090
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5870
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 6b 32 d4 10 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90002ed7198 EFLAGS: 00000206
RAX: 59b6fbc4dbd42200 RBX: 0000000000000000 RCX: 59b6fbc4dbd42200
RDX: 0000000000000000 RSI: ffffffff8d9219f6 RDI: ffffffff8bc0ffa0
RBP: ffffffff8171a9f5 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8171a9f5 R12: 0000000000000002
R13: ffffffff8df3d860 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf7/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xb05/0xcd0 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x161/0x1c0 mm/slub.c:3185
 put_cpu_partial+0x17c/0x250 mm/slub.c:3260
 __slab_free+0x2f7/0x400 mm/slub.c:4512
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4248
 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:658
 alloc_skb include/linux/skbuff.h:1340 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6639
 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2954
 unix_dgram_sendmsg+0x5c2/0x17c0 net/unix/af_unix.c:2007
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f56ee8c6407
RSP: 002b:00007ffd8756dbe0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f56ee776c80 RCX: 00007f56ee8c6407
RDX: 00000000000000a0 RSI: 00007ffd8756dd20 RDI: 0000000000000003
RBP: 00007ffd8756e150 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffd8756e168
R13: 00007ffd8756dd20 R14: 0000000000000085 R15: 00007ffd8756dd20
 </TASK>
net_ratelimit: 18139 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)


---
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Re: [syzbot] [mm?] INFO: rcu detected stall in vms_gather_munmap_vmas

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    86731a2a651e Linux 6.16-rc3
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14c41b0c580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=28cc6f051378bb16
dashboard link: https://syzkaller.appspot.com/bug?extid=701fc0fcde2b68c4bf59
compiler:       Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13e5e182580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4323a61a1fcd/disk-86731a2a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/646a4fb19be1/vmlinux-86731a2a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4235bfd16a36/bzImage-86731a2a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+701fc0fcde2b68c4bf59@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=095c/1/0x4000000000000000 softirq=18291/18292 fqs=1
rcu: 	(detected by 1, t=10504 jiffies, g=11509, q=2130 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6072 Comm: modprobe Not tainted 6.16.0-rc3-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__lock_acquire+0x80c/0xd20 kernel/locking/lockdep.c:-1
Code: d2 e9 c4 00 00 00 48 c7 c7 70 02 01 8e 48 89 de e8 39 98 51 03 eb c2 44 89 e0 25 ff 1f 00 00 41 c1 ec 03 41 81 e4 00 60 00 00 <41> 09 c4 4c 89 f9 48 c1 e9 20 89 ca c1 c2 04 41 29 cc 44 31 e2 44
RSP: 0018:ffffc90000007b30 EFLAGS: 00000046
RAX: 000000000000090a RBX: 0000000000000001 RCX: ffffffffffffffff
RDX: 00000000ffffc000 RSI: ffff88802f5fc718 RDI: ffff88802f5fbc00
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff897ed7f4
R10: dffffc0000000000 R11: ffffffff897ed730 R12: 0000000000000000
R13: ffff88802f5fc6f0 R14: ffff88802f5fc718 R15: ffffffffffffffff
FS:  0000000000000000(0000) GS:ffff888125c85000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd5919b74e8 CR3: 0000000073704000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 advance_sched+0xc4/0xc90 net/sched/sch_taprio.c:924
 __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:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:127 [inline]
RIP: 0010:lock_acquire+0xcd/0x360 kernel/locking/lockdep.c:5867
Code: 0f 85 eb 00 00 00 65 48 8b 04 25 08 b0 99 92 83 b8 ec 0a 00 00 00 0f 85 d5 00 00 00 48 c7 44 24 30 00 00 00 00 9c 8f 44 24 30 <4c> 89 74 24 10 4d 89 fe 4c 8b 7c 24 30 fa 48 c7 c7 f0 21 98 8d e8
RSP: 0018:ffffc90003abecd8 EFLAGS: 00000246
RAX: ffff88802f5fbc00 RBX: 0000000000000000 RCX: 48d8de1ae89d0f00
RDX: 0000000000000000 RSI: ffffffff81728b12 RDI: 1ffffffff1c27dcc
RBP: ffffffff81728af5 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90003abee98 R11: ffffffff81ace5b0 R12: 0000000000000002
R13: ffffffff8e13ee60 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:319 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4148 [inline]
 kmem_cache_alloc_bulk_noprof+0x4e0/0x790 mm/slub.c:5374
 mt_alloc_bulk lib/maple_tree.c:181 [inline]
 mas_alloc_nodes+0x447/0x8e0 lib/maple_tree.c:1271
 mas_node_count_gfp lib/maple_tree.c:1331 [inline]
 mas_preallocate+0x39e/0x6b0 lib/maple_tree.c:5532
 vma_iter_prealloc mm/vma.h:463 [inline]
 __split_vma+0x2fa/0xa00 mm/vma.c:525
 vms_gather_munmap_vmas+0x4ab/0x12b0 mm/vma.c:1375
 __mmap_prepare mm/vma.c:2351 [inline]
 __mmap_region mm/vma.c:2607 [inline]
 mmap_region+0x678/0x1f30 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: 0033:0x7fd5919e8242
Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00
RSP: 002b:00007ffc896f1078 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fd591742000 RCX: 00007fd5919e8242
RDX: 0000000000000005 RSI: 000000000014e000 RDI: 00007fd591742000
RBP: 0000000000000812 R08: 0000000000000000 R09: 0000000000028000
R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffc896f10c8
R13: 00007fd5919bc5f0 R14: 00007ffc896f18b0 R15: 00000fff912de212
 </TASK>
rcu: rcu_preempt kthread starved for 10500 jiffies! g11509 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27128 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16a2/0x4cb0 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: 1 UID: 0 PID: 5190 Comm: udevd Not tainted 6.16.0-rc3-syzkaller #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 60 78 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 0b 74 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 f0 73 0b
RSP: 0018:ffffc900030a7580 EFLAGS: 00000293
RAX: ffffffff81b4d830 RBX: ffff8880b873b040 RCX: ffff88807c598000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900030a76e0 R08: ffffffff8f9fe0f7 R09: 1ffffffff1f3fc1e
R10: dffffc0000000000 R11: fffffbfff1f3fc1f R12: 1ffff110170c835d
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641ae8
FS:  00007f8df5585880(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e81504cef0 CR3: 000000007c958000 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
 dup_mmap+0x15a0/0x1ac0 mm/mmap.c:1877
 dup_mm kernel/fork.c:1477 [inline]
 copy_mm+0x13c/0x4b0 kernel/fork.c:1529
 copy_process+0x1706/0x3c00 kernel/fork.c:2169
 kernel_clone+0x224/0x7f0 kernel/fork.c:2599
 __do_sys_clone kernel/fork.c:2742 [inline]
 __se_sys_clone kernel/fork.c:2726 [inline]
 __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726
 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: 0033:0x7f8df4ef1636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffffac3e030 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffffac3e038 RCX: 00007f8df4ef1636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055e814eac910 R08: 0000000000000000 R09: 000055e814eb4890
R10: 00007f8df5585b50 R11: 0000000000000246 R12: 00007ffffac3e3f0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


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