Extracting prog: 9m8.172496169s Minimizing prog: 24m30.061800036s Simplifying prog options: 0s Extracting C: 3m12.014357616s Simplifying C: 27m16.499343734s 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 1h4m6.748026558s repro crashed as (corrupted=false): INFO: task syz-executor214:5858 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor214 state:D stack:28008 pid:5858 tgid:5858 ppid:5857 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:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a3/0x830 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: 0033:0x7fb643b8cb29 RSP: 002b:00007ffc4379a418 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb643b8cb29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4379a638 R14: 00007ffc4379a440 R15: 00007ffc4379a430 INFO: task syz-executor214:5861 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor214 state:D stack:28008 pid:5861 tgid:5861 ppid:5859 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:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a3/0x830 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: 0033:0x7fb643b8cb29 RSP: 002b:00007ffc4379a418 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb643b8cb29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4379a638 R14: 00007ffc4379a440 R15: 00007ffc4379a430 INFO: task syz-executor214:5864 blocked for more than 144 seconds. Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor214 state:D stack:27112 pid:5864 tgid:5864 ppid:5863 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:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a3/0x830 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: 0033:0x7fb643b8cb29 RSP: 002b:00007ffc4379a418 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb643b8cb29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4379a638 R14: 00007ffc4379a440 R15: 00007ffc4379a430 Showing all locks held in the system: 2 locks held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by kworker/u8:4/65: #0: ffff8880b863b918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 #1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39a/0x6d0 kernel/sched/psi.c:987 2 locks held by getty/5596: #0: ffff88814c4010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor214/5858: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor214/5861: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 3 locks held by syz-executor214/5862: 1 lock held by syz-executor214/5864: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor214/5877: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:rcu_lockdep_current_cpu_online+0x60/0x120 kernel/rcu/tree.c:3994 Code: 09 89 c3 83 f8 08 0f 83 c7 00 00 00 49 be 00 00 00 00 00 fc ff df 48 8d 1c dd 60 6c ba 8d 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 c6 68 7c 00 48 8b 03 48 8d 98 00 a9 9e 92 48 8d RSP: 0018:ffffc900001d7778 EFLAGS: 00000246 RAX: 1ffffffff1b74d8d RBX: ffffffff8dba6c68 RCX: b9c373ea9cbee800 RDX: 0000000000000100 RSI: ffffffff8be28260 RDI: ffffffff8be28220 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff822d291e R10: 0000000000000008 R11: ffffffff81acf990 R12: 00000000000783c3 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000001000 FS: 0000000000000000(0000) GS:ffff888125d52000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555e38c6f8 CR3: 0000000077d7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 lookup_page_ext mm/page_ext.c:254 [inline] page_ext_lookup+0xe7/0x180 mm/page_ext.c:520 page_ext_iter_begin include/linux/page_ext.h:132 [inline] __update_page_owner_free_handle+0x103/0x470 mm/page_owner.c:272 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:309 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x286/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164 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: 1.167 msecs final repro crashed as (corrupted=false): INFO: task syz-executor214:5858 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor214 state:D stack:28008 pid:5858 tgid:5858 ppid:5857 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:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a3/0x830 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: 0033:0x7fb643b8cb29 RSP: 002b:00007ffc4379a418 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb643b8cb29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4379a638 R14: 00007ffc4379a440 R15: 00007ffc4379a430 INFO: task syz-executor214:5861 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor214 state:D stack:28008 pid:5861 tgid:5861 ppid:5859 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:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a3/0x830 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: 0033:0x7fb643b8cb29 RSP: 002b:00007ffc4379a418 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb643b8cb29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4379a638 R14: 00007ffc4379a440 R15: 00007ffc4379a430 INFO: task syz-executor214:5864 blocked for more than 144 seconds. Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor214 state:D stack:27112 pid:5864 tgid:5864 ppid:5863 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:867 [inline] blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 vfs_fallocate+0x6a3/0x830 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: 0033:0x7fb643b8cb29 RSP: 002b:00007ffc4379a418 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb643b8cb29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffc4379a638 R14: 00007ffc4379a440 R15: 00007ffc4379a430 Showing all locks held in the system: 2 locks held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by kworker/u8:4/65: #0: ffff8880b863b918 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606 #1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39a/0x6d0 kernel/sched/psi.c:987 2 locks held by getty/5596: #0: ffff88814c4010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor214/5858: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor214/5861: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 3 locks held by syz-executor214/5862: 1 lock held by syz-executor214/5864: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor214/5877: #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888022e8b5a0 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.15.0-syzkaller-13743-g8630c59e9936 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:rcu_lockdep_current_cpu_online+0x60/0x120 kernel/rcu/tree.c:3994 Code: 09 89 c3 83 f8 08 0f 83 c7 00 00 00 49 be 00 00 00 00 00 fc ff df 48 8d 1c dd 60 6c ba 8d 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 c6 68 7c 00 48 8b 03 48 8d 98 00 a9 9e 92 48 8d RSP: 0018:ffffc900001d7778 EFLAGS: 00000246 RAX: 1ffffffff1b74d8d RBX: ffffffff8dba6c68 RCX: b9c373ea9cbee800 RDX: 0000000000000100 RSI: ffffffff8be28260 RDI: ffffffff8be28220 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff822d291e R10: 0000000000000008 R11: ffffffff81acf990 R12: 00000000000783c3 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000001000 FS: 0000000000000000(0000) GS:ffff888125d52000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555e38c6f8 CR3: 0000000077d7e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:113 [inline] rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349 lookup_page_ext mm/page_ext.c:254 [inline] page_ext_lookup+0xe7/0x180 mm/page_ext.c:520 page_ext_iter_begin include/linux/page_ext.h:132 [inline] __update_page_owner_free_handle+0x103/0x470 mm/page_owner.c:272 __reset_page_owner+0x85/0x1f0 mm/page_owner.c:309 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x286/0x870 kernel/softirq.c:579 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968 smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164 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: 1.167 msecs