rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2658 jiffies s: 88309 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 16196 Comm: syz.3.3610 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:asm_sysvec_irq_work+0x0/0x20 arch/x86/include/asm/idtentry.h:722 Code: e9 b5 03 00 00 90 90 90 90 90 0f 01 ca fc 6a ff e8 b5 02 00 00 48 89 c4 48 89 e7 e8 ea b0 ed ff e9 95 03 00 00 90 90 90 90 90 <0f> 01 ca fc 6a ff e8 95 02 00 00 48 89 c4 48 89 e7 e8 ba b5 ed ff RSP: 0018:ffffc9000e9ff3d8 EFLAGS: 00000006 RAX: cf4c417510f88500 RBX: 1ffff92001d3fe88 RCX: cf4c417510f88500 RDX: dffffc0000000000 RSI: ffffffff8a8c1120 RDI: ffffffff8adf1320 RBP: ffffc9000e9ff4f0 R08: ffffffff90af92df R09: 1ffffffff215f25b R10: dffffc0000000000 R11: fffffbfff215f25c R12: 0000000000000246 R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001 FS: 00007f412a7386c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f965394da08 CR3: 0000000062ec4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: 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 d2 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:ffffc9000e9ff400 EFLAGS: 00000206 __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: 0033:0x7f412979cdd9 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:00007f412a737fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f4129a15fa0 RCX: 00007f412979cdd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000011 RBP: 00007f4129832d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f4129a16038 R14: 00007f4129a15fa0 R15: 00007fff2aa94558