Extracting prog: 8m7.186447088s Minimizing prog: 24m33.163416934s Simplifying prog options: 0s Extracting C: 3m14.097359419s Simplifying C: 26m52.016485597s 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 1h2m46.46373533s repro crashed as (corrupted=false): INFO: task syz-executor355:5858 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor355 state:D stack:27768 pid:5858 tgid:5858 ppid:5856 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 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+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: 0033:0x7f00824e0b29 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 INFO: task syz-executor355:5859 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor355 state:D stack:28040 pid:5859 tgid:5859 ppid:5857 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 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+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: 0033:0x7f00824e0b29 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 INFO: task syz-executor355:5861 blocked for more than 144 seconds. Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor355 state:D stack:28040 pid:5861 tgid:5861 ppid:5860 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 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+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: 0033:0x7f00824e0b29 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5598: #0: ffff88803078d0a0 (&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 2 locks held by syz-executor355/5855: 1 lock held by syz-executor355/5858: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor355/5859: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor355/5861: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor355/5873: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&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 6.15.0-syzkaller-08297-ge0797d3b91de #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:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/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: 5855 Comm: syz-executor355 Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:check_preemption_disabled+0x17/0x120 lib/smp_processor_id.c:14 Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 9e d0 37 07 48 89 44 24 08 <65> 8b 05 a6 d0 37 07 65 8b 0d 9b d0 37 07 f7 c1 ff ff ff 7f 74 23 RSP: 0018:ffffc9000456edc0 EFLAGS: 00000086 RAX: 64bd9f1d0f1d2500 RBX: 0000000000000000 RCX: 64bd9f1d0f1d2500 RDX: 0000000000000000 RSI: ffffffff8db59fcc RDI: ffffffff8be26380 RBP: ffffffff81727865 R08: 0000000000000000 R09: ffffffff81727865 R10: ffffc9000456efb8 R11: ffffffff81acc920 R12: 0000000000000002 R13: ffffffff8e13ccc0 R14: 0000000000000000 R15: 0000000000000246 FS: 00005555723dd380(0000) GS:ffff888125c64000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555a106fc168 CR3: 0000000079620000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline] lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5873 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] slab_free_hook mm/slub.c:2332 [inline] slab_free mm/slub.c:4642 [inline] kmem_cache_free+0x166/0x400 mm/slub.c:4744 __bio_chain_endio block/bio.c:319 [inline] bio_endio+0x3f/0x870 block/bio.c:1628 blk_update_request+0x5eb/0xe70 block/blk-mq.c:987 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1149 nullb_complete_cmd drivers/block/null_blk/main.c:1402 [inline] null_handle_cmd drivers/block/null_blk/main.c:1454 [inline] null_queue_rq+0xbfe/0xe30 drivers/block/null_blk/main.c:1693 null_queue_rqs+0x123/0x270 drivers/block/null_blk/main.c:1707 __blk_mq_flush_list block/blk-mq.c:2826 [inline] blk_mq_dispatch_queue_requests+0x414/0x800 block/blk-mq.c:2871 blk_mq_flush_plug_list+0x432/0x550 block/blk-mq.c:2959 blk_add_rq_to_plug+0x175/0x450 block/blk-mq.c:1388 blk_mq_submit_bio+0xbd3/0x22d0 block/blk-mq.c:3208 __submit_bio+0x207/0x5a0 block/blk-core.c:635 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x505/0xb50 block/blk-core.c:751 bio_chain_and_submit+0xeb/0x130 block/bio.c:362 __blkdev_issue_zero_pages+0x24f/0x2c0 block/blk-lib.c:222 blkdev_issue_zero_pages block/blk-lib.c:238 [inline] blkdev_issue_zeroout+0x56c/0x7c0 block/blk-lib.c:325 blkdev_fallocate+0x3e6/0x4b0 block/fops.c:-1 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: 0033:0x7f00824e0b29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.351 msecs final repro crashed as (corrupted=false): INFO: task syz-executor355:5858 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor355 state:D stack:27768 pid:5858 tgid:5858 ppid:5856 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 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+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: 0033:0x7f00824e0b29 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 INFO: task syz-executor355:5859 blocked for more than 143 seconds. Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor355 state:D stack:28040 pid:5859 tgid:5859 ppid:5857 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 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+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: 0033:0x7f00824e0b29 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 INFO: task syz-executor355:5861 blocked for more than 144 seconds. Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor355 state:D stack:28040 pid:5861 tgid:5861 ppid:5860 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5392 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0x165/0x360 kernel/sched/core.c:6874 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931 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+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: 0033:0x7f00824e0b29 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5598: #0: ffff88803078d0a0 (&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 2 locks held by syz-executor355/5855: 1 lock held by syz-executor355/5858: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor355/5859: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor355/5861: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x1d8/0x4b0 block/fops.c:877 1 lock held by syz-executor355/5873: #0: ffff888148c2ef20 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888148c2ef20 (&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 6.15.0-syzkaller-08297-ge0797d3b91de #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:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/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: 5855 Comm: syz-executor355 Not tainted 6.15.0-syzkaller-08297-ge0797d3b91de #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:check_preemption_disabled+0x17/0x120 lib/smp_processor_id.c:14 Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 9e d0 37 07 48 89 44 24 08 <65> 8b 05 a6 d0 37 07 65 8b 0d 9b d0 37 07 f7 c1 ff ff ff 7f 74 23 RSP: 0018:ffffc9000456edc0 EFLAGS: 00000086 RAX: 64bd9f1d0f1d2500 RBX: 0000000000000000 RCX: 64bd9f1d0f1d2500 RDX: 0000000000000000 RSI: ffffffff8db59fcc RDI: ffffffff8be26380 RBP: ffffffff81727865 R08: 0000000000000000 R09: ffffffff81727865 R10: ffffc9000456efb8 R11: ffffffff81acc920 R12: 0000000000000002 R13: ffffffff8e13ccc0 R14: 0000000000000000 R15: 0000000000000246 FS: 00005555723dd380(0000) GS:ffff888125c64000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555a106fc168 CR3: 0000000079620000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline] lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5873 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] slab_free_hook mm/slub.c:2332 [inline] slab_free mm/slub.c:4642 [inline] kmem_cache_free+0x166/0x400 mm/slub.c:4744 __bio_chain_endio block/bio.c:319 [inline] bio_endio+0x3f/0x870 block/bio.c:1628 blk_update_request+0x5eb/0xe70 block/blk-mq.c:987 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1149 nullb_complete_cmd drivers/block/null_blk/main.c:1402 [inline] null_handle_cmd drivers/block/null_blk/main.c:1454 [inline] null_queue_rq+0xbfe/0xe30 drivers/block/null_blk/main.c:1693 null_queue_rqs+0x123/0x270 drivers/block/null_blk/main.c:1707 __blk_mq_flush_list block/blk-mq.c:2826 [inline] blk_mq_dispatch_queue_requests+0x414/0x800 block/blk-mq.c:2871 blk_mq_flush_plug_list+0x432/0x550 block/blk-mq.c:2959 blk_add_rq_to_plug+0x175/0x450 block/blk-mq.c:1388 blk_mq_submit_bio+0xbd3/0x22d0 block/blk-mq.c:3208 __submit_bio+0x207/0x5a0 block/blk-core.c:635 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x505/0xb50 block/blk-core.c:751 bio_chain_and_submit+0xeb/0x130 block/bio.c:362 __blkdev_issue_zero_pages+0x24f/0x2c0 block/blk-lib.c:222 blkdev_issue_zero_pages block/blk-lib.c:238 [inline] blkdev_issue_zeroout+0x56c/0x7c0 block/blk-lib.c:325 blkdev_fallocate+0x3e6/0x4b0 block/fops.c:-1 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: 0033:0x7f00824e0b29 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffea60d2008 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f00824e0b29 RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000004 RBP: 00000000000f4240 R08: 00000000000000a0 R09: 00000000000000a0 R10: 0000002000000400 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffea60d2228 R14: 00007ffea60d2030 R15: 00007ffea60d2020 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.351 msecs