Extracting prog: 8m23.822018874s Minimizing prog: 24m27.907862637s Simplifying prog options: 0s Extracting C: 3m9.482334017s Simplifying C: 26m55.632169661s extracting reproducer from 1 programs testing a last program of every proc single: executing 1 programs separately with timeout 30s testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000080), 0x162e02, 0x0) r1 = dup(r0) fallocate(r1, 0x10, 0x0, 0x2000000400) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 1m40s testing program (duration=1m40s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000080), 0x162e02, 0x0) r1 = dup(r0) fallocate(r1, 0x10, 0x0, 0x2000000400) program did not crash single: failed to extract reproducer single: executing 1 programs separately with timeout 6m0s testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000080), 0x162e02, 0x0) r1 = dup(r0) fallocate(r1, 0x10, 0x0, 0x2000000400) program crashed: INFO: task hung in blkdev_fallocate single: successfully extracted reproducer found reproducer with 3 syscalls minimizing guilty program testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, &(0x7f0000000080), 0x162e02, 0x0) dup(r0) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-fallocate detailed listing: executing program 0: openat$nullb(0xffffffffffffff9c, &(0x7f0000000080), 0x162e02, 0x0) fallocate(0xffffffffffffffff, 0x10, 0x0, 0x2000000400) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): dup-fallocate detailed listing: executing program 0: r0 = dup(0xffffffffffffffff) fallocate(r0, 0x10, 0x0, 0x2000000400) program did not crash testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate detailed listing: executing program 0: r0 = openat$nullb(0xffffffffffffff9c, 0x0, 0x162e02, 0x0) r1 = dup(r0) fallocate(r1, 0x10, 0x0, 0x2000000400) program did not crash extracting C reproducer testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate simplifying C reproducer testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: no output from test machine a never seen crash title: no output from test machine, ignore testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$nullb-dup-fallocate program crashed: INFO: task hung in blkdev_fallocate reproducing took 1h2m56.844403494s repro crashed as (corrupted=false): INFO: task syz-executor114:5856 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor114 state:D stack:28008 pid:5856 tgid:5856 ppid:5854 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:869 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a0/0x830 fs/open.c:341 ksys_fallocate fs/open.c:365 [inline] __do_sys_fallocate fs/open.c:370 [inline] __se_sys_fallocate fs/open.c:368 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd447ea6b29 RSP: 002b:00007ffc9f938928 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd447ea6b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc9f938b48 R14: 00007ffc9f938950 R15: 00007ffc9f938940 INFO: task syz-executor114:5858 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor114 state:D stack:28008 pid:5858 tgid:5858 ppid:5855 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:869 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a0/0x830 fs/open.c:341 ksys_fallocate fs/open.c:365 [inline] __do_sys_fallocate fs/open.c:370 [inline] __se_sys_fallocate fs/open.c:368 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd447ea6b29 RSP: 002b:00007ffc9f938928 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd447ea6b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc9f938b48 R14: 00007ffc9f938950 R15: 00007ffc9f938940 INFO: task syz-executor114:5859 blocked for more than 144 seconds. Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor114 state:D stack:28264 pid:5859 tgid:5859 ppid:5853 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:869 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a0/0x830 fs/open.c:341 ksys_fallocate fs/open.c:365 [inline] __do_sys_fallocate fs/open.c:370 [inline] __se_sys_fallocate fs/open.c:368 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd447ea6b29 RSP: 002b:00007ffc9f938928 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd447ea6b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc9f938b48 R14: 00007ffc9f938950 R15: 00007ffc9f938940 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 1 lock held by klogd/5188: 2 locks held by getty/5596: #0: ffff888034c3a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000362b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor114/5856: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 4 locks held by syz-executor114/5857: 1 lock held by syz-executor114/5858: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor114/5859: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor114/5866: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 1097 Comm: kworker/u8:6 Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:36 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_x2apic_icr_write arch/x86/include/asm/apic.h:233 [inline] RIP: 0010:__x2apic_send_IPI_dest arch/x86/kernel/apic/x2apic_phys.c:113 [inline] RIP: 0010:x2apic_send_IPI+0x73/0xe0 arch/x86/kernel/apic/x2apic_phys.c:50 Code: 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 75 42 41 8b 16 0f ae f0 0f ae e8 83 fb 02 b8 00 04 00 00 0f 45 c3 b9 30 08 00 00 0f 30 <66> 90 5b 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 89 fe 89 fd 48 c7 RSP: 0018:ffffc90003b1f670 EFLAGS: 00000206 RAX: 00000000000000fb RBX: 00000000000000fb RCX: 0000000000000830 RDX: 0000000000000001 RSI: 00000000000000fb RDI: 0000000000000001 RBP: ffffc90003b1f800 R08: ffffffff8fa10df7 R09: 1ffffffff1f421be R10: dffffc0000000000 R11: ffffffff81703110 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff8880b87201b0 R15: ffffffff8dba7c68 FS: 0000000000000000(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb69acacfb3 CR3: 000000000df38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_send_call_function_single_ipi arch/x86/include/asm/smp.h:95 [inline] send_call_function_single_ipi kernel/smp.c:118 [inline] smp_call_function_many_cond+0xc8f/0x12d0 kernel/smp.c:867 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline] smp_text_poke_batch_finish+0xe6a/0x1100 arch/x86/kernel/alternative.c:2984 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:855 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.089 msecs final repro crashed as (corrupted=false): INFO: task syz-executor114:5856 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor114 state:D stack:28008 pid:5856 tgid:5856 ppid:5854 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:869 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a0/0x830 fs/open.c:341 ksys_fallocate fs/open.c:365 [inline] __do_sys_fallocate fs/open.c:370 [inline] __se_sys_fallocate fs/open.c:368 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd447ea6b29 RSP: 002b:00007ffc9f938928 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd447ea6b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc9f938b48 R14: 00007ffc9f938950 R15: 00007ffc9f938940 INFO: task syz-executor114:5858 blocked for more than 143 seconds. Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor114 state:D stack:28008 pid:5858 tgid:5858 ppid:5855 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:869 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a0/0x830 fs/open.c:341 ksys_fallocate fs/open.c:365 [inline] __do_sys_fallocate fs/open.c:370 [inline] __se_sys_fallocate fs/open.c:368 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd447ea6b29 RSP: 002b:00007ffc9f938928 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd447ea6b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc9f938b48 R14: 00007ffc9f938950 R15: 00007ffc9f938940 INFO: task syz-executor114:5859 blocked for more than 144 seconds. Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor114 state:D stack:28264 pid:5859 tgid:5859 ppid:5853 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935 rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176 __down_write_common kernel/locking/rwsem.c:1304 [inline] __down_write kernel/locking/rwsem.c:1313 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578 inode_lock include/linux/fs.h:869 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a0/0x830 fs/open.c:341 ksys_fallocate fs/open.c:365 [inline] __do_sys_fallocate fs/open.c:370 [inline] __se_sys_fallocate fs/open.c:368 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:368 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd447ea6b29 RSP: 002b:00007ffc9f938928 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd447ea6b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc9f938b48 R14: 00007ffc9f938950 R15: 00007ffc9f938940 Showing all locks held in the system: 1 lock held by ksoftirqd/0/15: 1 lock held by khungtaskd/31: #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 1 lock held by klogd/5188: 2 locks held by getty/5596: #0: ffff888034c3a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000362b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor114/5856: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 4 locks held by syz-executor114/5857: 1 lock held by syz-executor114/5858: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor114/5859: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor114/5866: #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff888022ceaa20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 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: 1097 Comm: kworker/u8:6 Not tainted 6.16.0-rc2-syzkaller-00308-gf7301f856d35 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:36 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_x2apic_icr_write arch/x86/include/asm/apic.h:233 [inline] RIP: 0010:__x2apic_send_IPI_dest arch/x86/kernel/apic/x2apic_phys.c:113 [inline] RIP: 0010:x2apic_send_IPI+0x73/0xe0 arch/x86/kernel/apic/x2apic_phys.c:50 Code: 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 75 42 41 8b 16 0f ae f0 0f ae e8 83 fb 02 b8 00 04 00 00 0f 45 c3 b9 30 08 00 00 0f 30 <66> 90 5b 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 89 fe 89 fd 48 c7 RSP: 0018:ffffc90003b1f670 EFLAGS: 00000206 RAX: 00000000000000fb RBX: 00000000000000fb RCX: 0000000000000830 RDX: 0000000000000001 RSI: 00000000000000fb RDI: 0000000000000001 RBP: ffffc90003b1f800 R08: ffffffff8fa10df7 R09: 1ffffffff1f421be R10: dffffc0000000000 R11: ffffffff81703110 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff8880b87201b0 R15: ffffffff8dba7c68 FS: 0000000000000000(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb69acacfb3 CR3: 000000000df38000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_send_call_function_single_ipi arch/x86/include/asm/smp.h:95 [inline] send_call_function_single_ipi kernel/smp.c:118 [inline] smp_call_function_many_cond+0xc8f/0x12d0 kernel/smp.c:867 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052 on_each_cpu include/linux/smp.h:71 [inline] smp_text_poke_sync_each_cpu arch/x86/kernel/alternative.c:2691 [inline] smp_text_poke_batch_finish+0xe6a/0x1100 arch/x86/kernel/alternative.c:2984 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_disable_cpuslocked+0xc5/0x1b0 kernel/jump_label.c:240 static_key_disable+0x1a/0x20 kernel/jump_label.c:248 toggle_allocation_gate+0x1a1/0x240 mm/kfence/core.c:855 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.089 msecs