INFO: task syz.6.3880:20134 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.3880 state:D stack:26232 pid:20134 tgid:20132 ppid:19782 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5504 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228 __schedule_loop kernel/sched/core.c:7307 [inline] schedule+0x164/0x360 kernel/sched/core.c:7322 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1798 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:775 [inline] __sock_sendmsg net/socket.c:790 [inline] ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738 __sys_sendmsg net/socket.c:2770 [inline] __do_sys_sendmsg net/socket.c:2775 [inline] __se_sys_sendmsg net/socket.c:2773 [inline] __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd0df59ce59 RSP: 002b:00007fd0e039d028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd0df816090 RCX: 00007fd0df59ce59 RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000003 RBP: 00007fd0df632e6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd0df816128 R14: 00007fd0df816090 R15: 00007ffe5d806ec8 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 29516 Comm: syz.3.6537 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:__wrmsrq arch/x86/include/asm/msr.h:80 [inline] RIP: 0010:arch_inlined_clockevent_set_next_coupled arch/x86/include/asm/clock_inlined.h:19 [inline] RIP: 0010:clockevent_set_next_coupled kernel/time/clockevents.c:318 [inline] RIP: 0010:clockevents_program_event+0x1b9/0x630 kernel/time/clockevents.c:360 Code: 3c 24 4c 89 fe e8 67 b5 fc ff 84 c0 0f 84 da 00 00 00 e8 aa ad 0f 00 48 8b 44 24 40 48 89 c2 48 c1 ea 20 b9 e0 06 00 00 0f 30 <4c> 8b 64 24 10 43 c6 44 2c 04 f8 31 c0 48 c7 44 24 20 0e 36 e0 45 RSP: 0018:ffffc90000a08ec0 EFLAGS: 00000007 RAX: 000000f59c71bede RBX: ffff8880b8723c80 RCX: 00000000000006e0 RDX: 00000000000000f5 RSI: 0000000000000014 RDI: 0000000000000040 RBP: ffffc90000a08f80 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000000 R12: ffff8880b8723cc8 R13: dffffc0000000000 R14: 0000000000000004 R15: 0000006d6db973b8 FS: 0000000000000000(0000) GS:ffff88812537b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f66afeed6c8 CR3: 000000004048a000 CR4: 00000000003526f0 Call Trace: hrtimer_rearm kernel/time/hrtimer.c:2141 [inline] __hrtimer_rearm_deferred+0x26c/0x420 kernel/time/hrtimer.c:2161 hrtimer_rearm_deferred_tif include/linux/hrtimer_rearm.h:53 [inline] hrtimer_rearm_deferred include/linux/hrtimer_rearm.h:62 [inline] __irq_exit_rcu+0x14e/0x220 kernel/softirq.c:734 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:write_comp_data kernel/kcov.c:246 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x10/0x90 kernel/kcov.c:314 Code: 09 cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 98 55 74 11 <65> 8b 0d b9 55 74 11 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 RSP: 0018:ffffc9000664f398 EFLAGS: 00000246 RAX: ffffffff8216b96b RBX: 0000000000000001 RCX: ffff888062b03e00 RDX: ffff888062b03e00 RSI: 0000000000000002 RDI: 0000000000000000 RBP: ffffc9000664f690 R08: ffffea0005577ff3 R09: 1ffffd4000aaeffe R10: dffffc0000000000 R11: fffff94000aaefff R12: 00000000166ff700 R13: ffff8880b37fbfe0 R14: 00007f248e200000 R15: 00007f248e1fc000 zap_present_folio_ptes mm/memory.c:1674 [inline] zap_present_ptes mm/memory.c:1730 [inline] do_zap_pte_range mm/memory.c:1832 [inline] zap_pte_range mm/memory.c:1934 [inline] zap_pmd_range mm/memory.c:2020 [inline] zap_pud_range mm/memory.c:2048 [inline] zap_p4d_range mm/memory.c:2069 [inline] __zap_vma_range+0x228b/0x4c70 mm/memory.c:2109 unmap_vmas+0x390/0x550 mm/memory.c:2178 exit_mmap+0x293/0x9f0 mm/mmap.c:1300 __mmput+0x118/0x420 kernel/fork.c:1181 exit_mm+0x221/0x2d0 kernel/exit.c:610 do_exit+0x6cd/0x2360 kernel/exit.c:992 do_group_exit+0x22d/0x2f0 kernel/exit.c:1147 get_signal+0x121b/0x12c0 kernel/signal.c:3038 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f248e99ce59 Code: Unable to access opcode bytes at 0x7f248e99ce2f. RSP: 002b:00007f248f7d7028 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: 0000000000000000 RBX: 00007f248ec15fa0 RCX: 00007f248e99ce59 RDX: 00000000000000cf RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f248ea32e6f R08: 0000000000000004 R09: 0000000000000000 R10: 00002000000029c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f248ec16038 R14: 00007f248ec15fa0 R15: 00007fff7d2c8db8