Extracting prog: 5m23.708294216s
Minimizing prog: 1h14m38.786701624s
Simplifying prog options: 0s
Extracting C: 38.249402443s
Simplifying C: 19m13.296075886s


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: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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb-timer_gettime-process_vm_writev
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)
timer_gettime(0x0, 0x0)
process_vm_writev(0x0, 0x0, 0x0, 0x0, 0x0, 0x0)

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: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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb-timer_gettime-process_vm_writev
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)
timer_gettime(0x0, 0x0)
process_vm_writev(0x0, 0x0, 0x0, 0x0, 0x0, 0x0)

program crashed: possible deadlock in n_tty_flush_buffer
single: successfully extracted reproducer
found reproducer with 11 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb-timer_gettime
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)
timer_gettime(0x0, 0x0)

program crashed: possible deadlock in n_tty_flush_buffer
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program crashed: possible deadlock in tty_buffer_flush
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-ioctl$EVIOCSFF-syz_open_dev$evdev
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-ioctl$EVIOCSFF-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
write$char_usb(0xffffffffffffffff, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-rt_sigprocmask-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
rt_sigprocmask(0x0, &(0x7f0000000000)={[0xfffffffffffffffd]}, 0x0, 0x8)
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-rt_sigprocmask-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
rt_sigprocmask(0x0, 0x0, 0x0, 0x0)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program crashed: possible deadlock in n_tty_flush_buffer
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-bpf$BPF_PROG_RAW_TRACEPOINT_LOAD-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
bpf$BPF_PROG_RAW_TRACEPOINT_LOAD(0x5, 0x0, 0x0)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program crashed: possible deadlock in n_tty_flush_buffer
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-bpf$PROG_LOAD-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
bpf$PROG_LOAD(0x5, 0x0, 0x0)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program crashed: possible deadlock in tty_buffer_flush
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program crashed: possible deadlock in n_tty_flush_buffer
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r0 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r0, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
ioctl$KDSKBENT(0xffffffffffffffff, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r0 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r0, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, 0x0)
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, 0x0)
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(0x0, 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040)="e2", 0x12d8)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, 0x0, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
detailed listing:
executing program 0:
r0 = syz_open_dev$tty1(0xc, 0x4, 0x1)
ioctl$KDSKBENT(r0, 0x4b47, &(0x7f0000000080)={0x0, 0x7f, 0x20f})
ioctl$EVIOCSFF(0xffffffffffffffff, 0x40304580, &(0x7f00000006c0)={0xd309bedfc70f16ed, 0x0, 0x2, {0x0, 0x1}, {0x7f, 0x2}, @cond=[{0x22f, 0x3ff, 0x404, 0x4, 0x1, 0xa}, {0x0, 0xa0, 0x1, 0x4, 0x7ff, 0xff01}]})
r1 = syz_open_dev$evdev(&(0x7f00000000c0), 0x2, 0x822b01)
write$char_usb(r1, &(0x7f0000000040), 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
simplifying C reproducer
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in n_tty_flush_buffer
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 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}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$tty1-ioctl$KDSKBENT-ioctl$EVIOCSFF-syz_open_dev$evdev-write$char_usb
program crashed: possible deadlock in tty_buffer_flush
reproducing took 1h39m54.040505596s
repro crashed as (corrupted=false):
======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc3-next-20250625-syzkaller #0 Not tainted
------------------------------------------------------
kworker/1:2/1208 is trying to acquire lock:
ffff88801a4a10b8 (&buf->lock){+.+.}-{4:4}, at: tty_buffer_flush+0x74/0x2b0 drivers/tty/tty_buffer.c:229

but task is already holding lock:
ffffffff8e130200 (console_lock){+.+.}-{0:0}, at: vc_SAK+0x28/0x220 drivers/tty/vt/vt_ioctl.c:999

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (console_lock){+.+.}-{0:0}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       console_lock+0x164/0x1b0 kernel/printk/printk.c:2849
       uart_configure_port drivers/tty/serial/serial_core.c:2570 [inline]
       serial_core_add_one_port drivers/tty/serial/serial_core.c:3130 [inline]
       serial_core_register_port+0xc73/0x2700 drivers/tty/serial/serial_core.c:3356
       serial8250_register_8250_port+0x16db/0x2050 drivers/tty/serial/8250/8250_core.c:827
       serial_pnp_probe+0x527/0x790 drivers/tty/serial/8250/8250_pnp.c:480
       pnp_device_probe+0x30b/0x4c0 drivers/pnp/driver.c:111
       call_driver_probe drivers/base/dd.c:-1 [inline]
       really_probe+0x26d/0x9a0 drivers/base/dd.c:657
       __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799
       driver_probe_device+0x4f/0x430 drivers/base/dd.c:829
       __driver_attach+0x452/0x700 drivers/base/dd.c:1215
       bus_for_each_dev+0x233/0x2b0 drivers/base/bus.c:370
       bus_add_driver+0x345/0x640 drivers/base/bus.c:678
       driver_register+0x23a/0x320 drivers/base/driver.c:249
       serial8250_init+0xc2/0x1c0 drivers/tty/serial/8250/8250_platform.c:315
       do_one_initcall+0x233/0x820 init/main.c:1269
       do_initcall_level+0x137/0x1f0 init/main.c:1331
       do_initcalls+0x69/0xd0 init/main.c:1347
       kernel_init_freeable+0x3d9/0x570 init/main.c:1579
       kernel_init+0x1d/0x1d0 init/main.c:1469
       ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #2 (&port->mutex){+.+.}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:602 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
       class_mutex_constructor include/linux/mutex.h:225 [inline]
       uart_set_termios+0x82/0x6f0 drivers/tty/serial/serial_core.c:1688
       tty_set_termios+0xca5/0x17e0 drivers/tty/tty_ioctl.c:341
       set_termios+0x516/0x6c0 drivers/tty/tty_ioctl.c:516
       tty_mode_ioctl+0x47e/0x740 drivers/tty/tty_ioctl.c:-1
       tty_ioctl+0x9c3/0xde0 drivers/tty/tty_io.c:2801
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:907 [inline]
       __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
       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

-> #1 (&tty->termios_rwsem){++++}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       down_read+0x46/0x2e0 kernel/locking/rwsem.c:1524
       n_tty_receive_buf_common+0x84/0x12f0 drivers/tty/n_tty.c:1686
       tty_port_default_receive_buf+0x6e/0xa0 drivers/tty/tty_port.c:37
       receive_buf drivers/tty/tty_buffer.c:445 [inline]
       flush_to_ldisc+0x24a/0x720 drivers/tty/tty_buffer.c:495
       process_one_work kernel/workqueue.c:3239 [inline]
       process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
       worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
       kthread+0x711/0x8a0 kernel/kthread.c:463
       ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #0 (&buf->lock){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3168 [inline]
       check_prevs_add kernel/locking/lockdep.c:3287 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
       __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:602 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
       tty_buffer_flush+0x74/0x2b0 drivers/tty/tty_buffer.c:229
       tty_ldisc_flush+0x6b/0xc0 drivers/tty/tty_ldisc.c:388
       __do_SAK+0x138/0x6d0 drivers/tty/tty_io.c:3025
       vc_SAK+0x78/0x220 drivers/tty/vt/vt_ioctl.c:1009
       process_one_work kernel/workqueue.c:3239 [inline]
       process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
       worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
       kthread+0x711/0x8a0 kernel/kthread.c:463
       ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

other info that might help us debug this:

Chain exists of:
  &buf->lock --> &port->mutex --> console_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(console_lock);
                               lock(&port->mutex);
                               lock(console_lock);
  lock(&buf->lock);

 *** DEADLOCK ***

4 locks held by kworker/1:2/1208:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
 #1: ffffc900043efbc0 ((work_completion)(&vc_cons[currcons].SAK_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
 #1: ffffc900043efbc0 ((work_completion)(&vc_cons[currcons].SAK_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
 #2: ffffffff8e130200 (console_lock){+.+.}-{0:0}, at: vc_SAK+0x28/0x220 drivers/tty/vt/vt_ioctl.c:999
 #3: ffff88802f90b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref drivers/tty/tty_ldisc.c:263 [inline]
 #3: ffff88802f90b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_flush+0x20/0xc0 drivers/tty/tty_ldisc.c:386

stack backtrace:
CPU: 1 UID: 0 PID: 1208 Comm: kworker/1:2 Not tainted 6.16.0-rc3-next-20250625-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events vc_SAK
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3168 [inline]
 check_prevs_add kernel/locking/lockdep.c:3287 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 __mutex_lock_common kernel/locking/mutex.c:602 [inline]
 __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
 tty_buffer_flush+0x74/0x2b0 drivers/tty/tty_buffer.c:229
 tty_ldisc_flush+0x6b/0xc0 drivers/tty/tty_ldisc.c:388
 __do_SAK+0x138/0x6d0 drivers/tty/tty_io.c:3025
 vc_SAK+0x78/0x220 drivers/tty/vt/vt_ioctl.c:1009
 process_one_work kernel/workqueue.c:3239 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

final repro crashed as (corrupted=false):
======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc3-next-20250625-syzkaller #0 Not tainted
------------------------------------------------------
kworker/1:2/1208 is trying to acquire lock:
ffff88801a4a10b8 (&buf->lock){+.+.}-{4:4}, at: tty_buffer_flush+0x74/0x2b0 drivers/tty/tty_buffer.c:229

but task is already holding lock:
ffffffff8e130200 (console_lock){+.+.}-{0:0}, at: vc_SAK+0x28/0x220 drivers/tty/vt/vt_ioctl.c:999

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (console_lock){+.+.}-{0:0}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       console_lock+0x164/0x1b0 kernel/printk/printk.c:2849
       uart_configure_port drivers/tty/serial/serial_core.c:2570 [inline]
       serial_core_add_one_port drivers/tty/serial/serial_core.c:3130 [inline]
       serial_core_register_port+0xc73/0x2700 drivers/tty/serial/serial_core.c:3356
       serial8250_register_8250_port+0x16db/0x2050 drivers/tty/serial/8250/8250_core.c:827
       serial_pnp_probe+0x527/0x790 drivers/tty/serial/8250/8250_pnp.c:480
       pnp_device_probe+0x30b/0x4c0 drivers/pnp/driver.c:111
       call_driver_probe drivers/base/dd.c:-1 [inline]
       really_probe+0x26d/0x9a0 drivers/base/dd.c:657
       __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799
       driver_probe_device+0x4f/0x430 drivers/base/dd.c:829
       __driver_attach+0x452/0x700 drivers/base/dd.c:1215
       bus_for_each_dev+0x233/0x2b0 drivers/base/bus.c:370
       bus_add_driver+0x345/0x640 drivers/base/bus.c:678
       driver_register+0x23a/0x320 drivers/base/driver.c:249
       serial8250_init+0xc2/0x1c0 drivers/tty/serial/8250/8250_platform.c:315
       do_one_initcall+0x233/0x820 init/main.c:1269
       do_initcall_level+0x137/0x1f0 init/main.c:1331
       do_initcalls+0x69/0xd0 init/main.c:1347
       kernel_init_freeable+0x3d9/0x570 init/main.c:1579
       kernel_init+0x1d/0x1d0 init/main.c:1469
       ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #2 (&port->mutex){+.+.}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:602 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
       class_mutex_constructor include/linux/mutex.h:225 [inline]
       uart_set_termios+0x82/0x6f0 drivers/tty/serial/serial_core.c:1688
       tty_set_termios+0xca5/0x17e0 drivers/tty/tty_ioctl.c:341
       set_termios+0x516/0x6c0 drivers/tty/tty_ioctl.c:516
       tty_mode_ioctl+0x47e/0x740 drivers/tty/tty_ioctl.c:-1
       tty_ioctl+0x9c3/0xde0 drivers/tty/tty_io.c:2801
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:907 [inline]
       __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
       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

-> #1 (&tty->termios_rwsem){++++}-{4:4}:
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       down_read+0x46/0x2e0 kernel/locking/rwsem.c:1524
       n_tty_receive_buf_common+0x84/0x12f0 drivers/tty/n_tty.c:1686
       tty_port_default_receive_buf+0x6e/0xa0 drivers/tty/tty_port.c:37
       receive_buf drivers/tty/tty_buffer.c:445 [inline]
       flush_to_ldisc+0x24a/0x720 drivers/tty/tty_buffer.c:495
       process_one_work kernel/workqueue.c:3239 [inline]
       process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
       worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
       kthread+0x711/0x8a0 kernel/kthread.c:463
       ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #0 (&buf->lock){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3168 [inline]
       check_prevs_add kernel/locking/lockdep.c:3287 [inline]
       validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
       __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
       lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
       __mutex_lock_common kernel/locking/mutex.c:602 [inline]
       __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
       tty_buffer_flush+0x74/0x2b0 drivers/tty/tty_buffer.c:229
       tty_ldisc_flush+0x6b/0xc0 drivers/tty/tty_ldisc.c:388
       __do_SAK+0x138/0x6d0 drivers/tty/tty_io.c:3025
       vc_SAK+0x78/0x220 drivers/tty/vt/vt_ioctl.c:1009
       process_one_work kernel/workqueue.c:3239 [inline]
       process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
       worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
       kthread+0x711/0x8a0 kernel/kthread.c:463
       ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

other info that might help us debug this:

Chain exists of:
  &buf->lock --> &port->mutex --> console_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(console_lock);
                               lock(&port->mutex);
                               lock(console_lock);
  lock(&buf->lock);

 *** DEADLOCK ***

4 locks held by kworker/1:2/1208:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
 #1: ffffc900043efbc0 ((work_completion)(&vc_cons[currcons].SAK_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
 #1: ffffc900043efbc0 ((work_completion)(&vc_cons[currcons].SAK_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
 #2: ffffffff8e130200 (console_lock){+.+.}-{0:0}, at: vc_SAK+0x28/0x220 drivers/tty/vt/vt_ioctl.c:999
 #3: ffff88802f90b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref drivers/tty/tty_ldisc.c:263 [inline]
 #3: ffff88802f90b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_flush+0x20/0xc0 drivers/tty/tty_ldisc.c:386

stack backtrace:
CPU: 1 UID: 0 PID: 1208 Comm: kworker/1:2 Not tainted 6.16.0-rc3-next-20250625-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events vc_SAK
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2046
 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2178
 check_prev_add kernel/locking/lockdep.c:3168 [inline]
 check_prevs_add kernel/locking/lockdep.c:3287 [inline]
 validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3911
 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
 __mutex_lock_common kernel/locking/mutex.c:602 [inline]
 __mutex_lock+0x182/0xe80 kernel/locking/mutex.c:747
 tty_buffer_flush+0x74/0x2b0 drivers/tty/tty_buffer.c:229
 tty_ldisc_flush+0x6b/0xc0 drivers/tty/tty_ldisc.c:388
 __do_SAK+0x138/0x6d0 drivers/tty/tty_io.c:3025
 vc_SAK+0x78/0x220 drivers/tty/vt/vt_ioctl.c:1009
 process_one_work kernel/workqueue.c:3239 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>