rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2676 jiffies s: 46629 root: 0x2/.
rcu: blocking rcu_node structures (internal RCU debug):
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12487 Comm: syz.2.2260 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:error_return+0x8/0x20 arch/x86/entry/entry_64.S:1123
Code: 02 00 89 d0 48 c1 ea 20 0f 30 0f 1f 44 00 00 48 8d 7c 24 08 e8 99 c5 ec ff 48 89 c7 eb 89 90 90 90 90 f6 84 24 88 00 00 00 03 <0f> 84 5f fd ff ff e9 fd fc ff ff 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90004647358 EFLAGS: 00000046
RAX: c4245c303802e600 RBX: 0000000000000000 RCX: c4245c303802e600
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60
RBP: 0000000000000000 R08: ffffffff90af62df R09: 1ffffffff215ec5b
R10: dffffc0000000000 R11: fffffbfff215ec5c R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f59d2b4c6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555641dd4e8 CR3: 0000000029335000 CR4: 00000000003506e0
DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000200000000800
DR3: 0000200000000800 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
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 e2 33 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:ffffc90004647400 EFLAGS: 00000206
RAX: c4245c303802e600 RBX: 1ffff920008c8e88 RCX: c4245c303802e600
RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60
RBP: ffffc900046474f0 R08: ffffffff90af62df R09: 1ffffffff215ec5b
R10: dffffc0000000000 R11: fffffbfff215ec5c R12: 0000000000000246
R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:823 [inline]
 page_ext_put+0x91/0xb0 mm/page_ext.c:182
 page_table_check_pte_set include/linux/page_table_check.h:83 [inline]
 set_pte_at arch/x86/include/asm/pgtable.h:1009 [inline]
 copy_present_pte mm/memory.c:1000 [inline]
 copy_pte_range mm/memory.c:1091 [inline]
 copy_pmd_range mm/memory.c:1177 [inline]
 copy_pud_range mm/memory.c:1214 [inline]
 copy_p4d_range mm/memory.c:1238 [inline]
 copy_page_range+0x24ea/0x3900 mm/memory.c:1332
 dup_mmap kernel/fork.c:702 [inline]
 dup_mm kernel/fork.c:1546 [inline]
 copy_mm+0xec3/0x1690 kernel/fork.c:1595
 copy_process+0x1979/0x4030 kernel/fork.c:2356
 kernel_clone+0x24b/0x900 kernel/fork.c:2762
 __do_sys_clone kernel/fork.c:2903 [inline]
 __se_sys_clone kernel/fork.c:2887 [inline]
 __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2887
 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: 0033:0x7f59d1b9c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f59d2b4bfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f59d1e15fa0 RCX: 00007f59d1b9c799
RDX: 0000200000000200 RSI: 00002000000001e0 RDI: 0000000000200200
RBP: 00007f59d1c32c99 R08: 0000200000000280 R09: 0000200000000280
R10: 0000200000000240 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f59d1e16038 R14: 00007f59d1e15fa0 R15: 00007ffdf8ce2368
 </TASK>