ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 watchdog: BUG: soft lockup - CPU#1 stuck for 245s! [kworker/u8:9:7163] Modules linked in: irq event stamp: 3973976 hardirqs last enabled at (3973975): [] kvm_wait arch/x86/kernel/kvm.c:1063 [inline] hardirqs last enabled at (3973975): [] kvm_wait+0x157/0x1f0 arch/x86/kernel/kvm.c:1045 hardirqs last disabled at (3973976): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1049 softirqs last enabled at (3973972): [] softirq_handle_end kernel/softirq.c:425 [inline] softirqs last enabled at (3973972): [] handle_softirqs+0x5be/0x8e0 kernel/softirq.c:607 softirqs last disabled at (3973931): [] __do_softirq kernel/softirq.c:613 [inline] softirqs last disabled at (3973931): [] invoke_softirq kernel/softirq.c:453 [inline] softirqs last disabled at (3973931): [] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:680 CPU: 1 UID: 0 PID: 7163 Comm: kworker/u8:9 Not tainted 6.15.0-rc3-syzkaller-00008-ga33b5a08cbbd #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: writeback wb_workfn (flush-8:0) RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:81 Code: 25 5f 02 e9 7e f4 9f f5 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d b3 8a 19 00 fb f4 57 f4 9f f5 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc900041ce690 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000006 RDX: ffff888028623c00 RSI: ffffffff81693531 RDI: ffffffff8bf45140 RBP: ffff88801b46e180 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90866917 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000003 R14: ffff8880b853ae40 R15: ffffed100368dc30 FS: 0000000000000000(0000) GS:ffff888124ab8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd9adbd7f98 CR3: 000000005e9cc000 CR4: 0000000000350ef0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] kvm_wait arch/x86/kernel/kvm.c:1063 [inline] kvm_wait+0x186/0x1f0 arch/x86/kernel/kvm.c:1045 pv_wait arch/x86/include/asm/paravirt.h:584 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:466 [inline] __pv_queued_spin_lock_slowpath+0x4e1/0xcf0 kernel/locking/qspinlock.c:325 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:572 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x20e/0x2b0 kernel/locking/spinlock_debug.c:116 spin_lock include/linux/spinlock.h:351 [inline] __pte_offset_map_lock+0xf0/0x2f0 mm/pgtable-generic.c:402 pte_offset_map_lock include/linux/mm.h:3149 [inline] map_pte mm/page_vma_mapped.c:23 [inline] page_vma_mapped_walk+0x1d67/0x2d10 mm/page_vma_mapped.c:292 page_vma_mkclean_one.constprop.0+0x2ee/0x7e0 mm/rmap.c:1039 page_mkclean_one+0x183/0x230 mm/rmap.c:1100 __rmap_walk_file+0x359/0x620 mm/rmap.c:2897 rmap_walk_file+0x174/0x1f0 mm/rmap.c:2930 rmap_walk mm/rmap.c:2941 [inline] folio_mkclean+0x251/0x3f0 mm/rmap.c:1132 folio_clear_dirty_for_io+0x153/0x810 mm/page-writeback.c:2987 mpage_submit_folio+0x80/0x350 fs/ext4/inode.c:1918 mpage_process_page_bufs+0x47c/0x9a0 fs/ext4/inode.c:2050 mpage_prepare_extent_to_map+0x759/0x1460 fs/ext4/inode.c:2551 ext4_do_writepages+0x9af/0x3490 fs/ext4/inode.c:2692 ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:2829 do_writepages+0x1b5/0x820 mm/page-writeback.c:2656 __writeback_single_inode+0x160/0xfb0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x601/0xf90 fs/fs-writeback.c:1976 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2047 wb_writeback+0x7f3/0xb70 fs/fs-writeback.c:2158 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline] wb_do_writeback fs/fs-writeback.c:2315 [inline] wb_workfn+0x8ca/0xbe0 fs/fs-writeback.c:2343 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c5/0x780 kernel/kthread.c:464 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9513 Comm: syz.3.1343 Not tainted 6.15.0-rc3-syzkaller-00008-ga33b5a08cbbd #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline] RIP: 0010:debug_deactivate kernel/time/hrtimer.c:490 [inline] RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1729 [inline] RIP: 0010:__hrtimer_run_queues+0x467/0xad0 kernel/time/hrtimer.c:1825 Code: d2 0f 85 a0 05 00 00 8b 2d 6a 2c de 0e 31 ff 89 ee e8 4d ce 12 00 85 ed 0f 85 fb 03 00 00 e8 00 d3 12 00 48 c7 c6 c0 d7 8f 8b <4c> 89 f7 e8 31 81 2a 03 4c 89 f7 e8 49 e0 ff ff 8b 6c 24 38 48 89 RSP: 0018:ffffc90000007e40 EFLAGS: 00000046 RAX: 0000000080010002 RBX: ffff8880b8427940 RCX: ffffffff81a87055 RDX: ffff88801f3ebc00 RSI: ffffffff8b8fd7c0 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: ffffffff9ad90918 R12: ffff8880b8427840 R13: 184986abfc000000 R14: ffff888057965340 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8881249b8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c331f83 CR3: 000000006f2a0000 CR4: 0000000000350ef0 Call Trace: hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:const_folio_flags.constprop.0+0x44/0x70 include/linux/page-flags.h:350 Code: fa 48 c1 ea 03 80 3c 02 00 75 3c 48 8b 6b 08 31 ff 83 e5 01 48 89 ee e8 5a 81 b6 ff 48 85 ed 75 0f e8 e0 85 b6 ff 48 89 d8 5b <5d> e9 a1 87 0b ff e8 d1 85 b6 ff 48 c7 c6 40 39 9b 8b 48 89 df e8 RSP: 0018:ffffc9000aab7828 EFLAGS: 00000293 RAX: ffffea0001dd8140 RBX: 8000000077605025 RCX: ffffffff8204b956 RDX: ffff88801f3ebc00 RSI: ffffffff8204b960 RDI: 0000000000000007 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff8880314be8c0 folio_test_swapbacked include/linux/page-flags.h:574 [inline] mm_counter_file include/linux/mm.h:2737 [inline] mm_counter include/linux/mm.h:2746 [inline] zap_present_folio_ptes mm/memory.c:1511 [inline] zap_present_ptes mm/memory.c:1586 [inline] do_zap_pte_range mm/memory.c:1687 [inline] zap_pte_range mm/memory.c:1731 [inline] zap_pmd_range mm/memory.c:1823 [inline] zap_pud_range mm/memory.c:1852 [inline] zap_p4d_range mm/memory.c:1873 [inline] unmap_page_range+0x1e14/0x4390 mm/memory.c:1894 unmap_single_vma+0x194/0x2a0 mm/memory.c:1940 unmap_vmas+0x22c/0x490 mm/memory.c:1984 exit_mmap+0x1b9/0xb90 mm/mmap.c:1284 __mmput+0x12a/0x410 kernel/fork.c:1379 mmput+0x62/0x70 kernel/fork.c:1401 exit_mm kernel/exit.c:589 [inline] do_exit+0x9d1/0x2c30 kernel/exit.c:940 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102 __do_sys_exit_group kernel/exit.c:1113 [inline] __se_sys_exit_group kernel/exit.c:1111 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1111 x64_sys_call+0x1530/0x1730 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f81c3b8e169 Code: Unable to access opcode bytes at 0x7f81c3b8e13f. RSP: 002b:00007ffc25fc6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f81c3b8e169 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffc25fc608c R08: 0000000425fc611f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 00000000000000ef R13: 00000000000927c0 R14: 000000000004948a R15: 00007ffc25fc60e0