watchdog: BUG: soft lockup - CPU#1 stuck for 246s! [syz.1.5516:20885] Modules linked in: irq event stamp: 1401056 hardirqs last enabled at (1401055): [] irqentry_exit+0x1dd/0x8c0 kernel/entry/common.c:219 hardirqs last disabled at (1401056): [] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1056 softirqs last enabled at (1401052): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last enabled at (1401052): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last enabled at (1401052): [] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 softirqs last disabled at (1400761): [] __do_softirq kernel/softirq.c:656 [inline] softirqs last disabled at (1400761): [] invoke_softirq kernel/softirq.c:496 [inline] softirqs last disabled at (1400761): [] __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723 CPU: 1 UID: 0 PID: 20885 Comm: syz.1.5516 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline] RIP: 0010:smp_call_function_many_cond+0xe02/0x15e0 kernel/smp.c:877 Code: 10 4c 89 74 24 10 49 89 d5 48 89 d5 48 89 54 24 18 49 c1 ed 03 83 e5 07 4d 01 e5 83 c5 03 e8 65 5b 0c 00 f3 90 41 0f b6 45 00 <40> 38 c5 7c 08 84 c0 0f 85 b6 05 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc900035576d0 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b8443020 RCX: ffffffff81b278d1 RDX: ffff88801cb90000 RSI: ffffffff81b278ab RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: ffff88801cb90b30 R12: dffffc0000000000 R13: ffffed1017088605 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124a08000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000f000 CR3: 000000005587f000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1043 __flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline] flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline] flush_tlb_mm_range+0x2f0/0x12c0 arch/x86/mm/tlb.c:1472 tlb_flush arch/x86/include/asm/tlb.h:23 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline] tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:480 [inline] tlb_flush_mmu mm/mmu_gather.c:403 [inline] tlb_finish_mmu+0x3c9/0x7c0 mm/mmu_gather.c:497 exit_mmap+0x3f9/0xb60 mm/mmap.c:1290 __mmput+0x12a/0x410 kernel/fork.c:1173 mmput+0x62/0x70 kernel/fork.c:1196 exit_mm kernel/exit.c:581 [inline] do_exit+0x7d7/0x2bd0 kernel/exit.c:959 do_group_exit+0xd3/0x2a0 kernel/exit.c:1112 get_signal+0x2671/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x8c/0x540 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ee/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f825d58f749 Code: Unable to access opcode bytes at 0x7f825d58f71f. RSP: 002b:00007f825b7f60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f825d7e5fa8 RCX: 00007f825d58f749 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f825d7e5fa8 RBP: 00007f825d7e5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f825d7e6038 R14: 00007fff3307f2c0 R15: 00007fff3307f3a8 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 20881 Comm: syz.6.5507 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:cpu_max_bits_warn include/linux/cpumask.h:138 [inline] RIP: 0010:cpumask_check include/linux/cpumask.h:145 [inline] RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:649 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1231 [inline] RIP: 0010:trace_hrtimer_expire_exit include/trace/events/timer.h:306 [inline] RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1780 [inline] RIP: 0010:__hrtimer_run_queues+0x258/0xc40 kernel/time/hrtimer.c:1841 Code: 5b 09 00 00 48 8b 44 24 18 c7 80 18 0b 00 00 00 00 00 00 e8 aa 1d 14 00 0f 1f 44 00 00 e8 a0 1d 14 00 65 44 8b 2d bc c9 06 12 07 00 00 00 44 89 ee e8 2b 18 14 00 41 83 fd 07 0f 87 56 08 00 RSP: 0018:ffffc90000007e40 EFLAGS: 00000046 RAX: 0000000080010001 RBX: ffff8880b8428540 RCX: ffffc90000007d54 RDX: ffff88803b6f9e80 RSI: ffffffff81aab670 RDI: ffff88803b6fa998 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff88803b6fa9b0 R12: ffff8880b8428440 R13: 0000000000000000 R14: ffff88804f729300 R15: 0000000000000001 FS: 00007f07a1b746c0(0000) GS:ffff888124908000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2db23ffc CR3: 0000000058199000 CR4: 0000000000350ef0 Call Trace: hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline] __sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:folios_put_refs+0x57/0x750 mm/swap.c:952 Code: c7 44 24 40 b3 8a b5 41 48 c1 e8 03 48 c7 44 24 48 e8 ab bd 8d 49 89 c7 48 01 d8 48 c7 44 24 50 30 8c fb 81 c7 00 f1 f1 f1 f1 40 04 00 f2 f2 f2 c7 40 08 00 f3 f3 f3 65 48 8b 05 6b f3 b5 11 RSP: 0018:ffffc90003f8f6f8 EFLAGS: 00000286 RAX: fffff520007f1ee7 RBX: dffffc0000000000 RCX: ffffc90010856000 RDX: 0000000000080000 RSI: 0000000000000000 RDI: ffff8880b8433ab0 RBP: 000000000000001f R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff90883dd7 R11: ffff88803b6fa9b0 R12: 000000000000001f R13: ffff8880b8433bb0 R14: ffff8880b8433ab0 R15: 1ffff920007f1ee7 folios_put include/linux/mm.h:1671 [inline] folio_batch_move_lru+0x278/0x3a0 mm/swap.c:179 __folio_batch_add_and_move+0x318/0xc30 mm/swap.c:196 shmem_alloc_and_add_folio+0x835/0xc20 mm/shmem.c:1991 shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556 shmem_get_folio mm/shmem.c:2662 [inline] shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315 generic_perform_write+0x3c4/0x900 mm/filemap.c:4314 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7d3/0x11d0 fs/read_write.c:686 ksys_write+0x12a/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f07a0d8e1ff Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48 RSP: 002b:00007f07a1b73df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007f07a0d8e1ff RDX: 0000000001000000 RSI: 00007f0796a00000 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000050ed R10: 000020000000a2c2 R11: 0000000000000293 R12: 0000000000000003 R13: 00007f07a1b73ef0 R14: 00007f07a1b73eb0 R15: 00007f0796a00000