Got on 2 different installations in different virtualization platform.
Second start panic after system update, so something was broken after 14 apr.
Panic fast on heavy load.


Unread portion of the kernel message buffer:
[104228] interrupt                   total
[104228] irq1: atkbd0                           2
[104228] irq0: hpet0:t0                  12359529
[104228] irq8: hpet0:t1                   3042994
[104228] irq11: uhci0+                         17
[104228] irq15: ata1                        69310
[104228] irq25: virtio_pci1                     6
[104228] irq27: virtio_pci1                 86958
[104228] irq29: virtio_pci2               3748776
[104228] irq30: virtio_pci2                     7
[104228] Total                    19307599
[104228] panic: watchdog timeout
[104228] cpuid = 0
[104228] time = 1687914426
[104228] KDB: stack backtrace:
[104228] #0 0xffffffff8062e60b at kdb_backtrace+0x6b
[104228] #1 0xffffffff805e5232 at vpanic+0x152
[104228] #2 0xffffffff805e50d3 at panic+0x43
[104228] #3 0xffffffff805835da at hardclock+0x29a
[104228] #4 0xffffffff805842bf at handleevents+0xaf
[104228] #5 0xffffffff80584e89 at timercb+0x1d9
[104228] #6 0xffffffff80886e95 at hpet_intr_single+0x1c5
[104228] #7 0xffffffff805b0dd8 at intr_event_handle+0xd8
[104228] #8 0xffffffff808c0420 at intr_execute_handlers+0x50
[104228] #9 0xffffffff808ced8c at Xapic_isr1+0xdc
[104228] #10 0xffffffff808bc0b8 at cpu_idle+0xa8
[104228] #11 0xffffffff806157b1 at sched_idletd+0x4e1
[104228] #12 0xffffffff805ade26 at fork_exit+0x76
[104228] #13 0xffffffff808cebde at fork_trampoline+0xe
[104228] Uptime: 1d4h57m8s
[104228] Dumping 637 out of 4078 MB:..3%..11%..21%..31%..41%..51%..61%..71%..81%..91%

__curthread () at /usr/src/sys/amd64/include/pcpu_aux.h:55
55              __asm("movq %%gs:%P1,%0" : "=r" (td) : "n" (offsetof(struct pcpu,
(kgdb) #0  __curthread () at /usr/src/sys/amd64/include/pcpu_aux.h:55
#1  doadump (textdump=<optimized out>)
    at ../../../sys/kern/kern_shutdown.c:396
#2  0xffffffff805e4e28 in kern_reboot (howto=260)
    at ../../../sys/kern/kern_shutdown.c:484
#3  0xffffffff805e529f in vpanic (fmt=<optimized out>,
    ap=ap@entry=0xfffffe00084b1bb0) at ../../../sys/kern/kern_shutdown.c:923
#4  0xffffffff805e50d3 in panic (fmt=<unavailable>)
    at ../../../sys/kern/kern_shutdown.c:847
#5  0xffffffff805835da in watchdog_fire ()
    at ../../../sys/kern/kern_clock.c:849
#6  hardclock (cnt=<optimized out>, usermode=<optimized out>)
    at ../../../sys/kern/kern_clock.c:505
#7  0xffffffff805842bf in handleevents (now=now@entry=447657490799483,
    fake=fake@entry=0) at ../../../sys/kern/kern_clocksource.c:187
#8  0xffffffff80584e89 in timercb (et=0xfffffe00a3faa0b0, arg=<optimized out>)
    at ../../../sys/kern/kern_clocksource.c:355
#9  0xffffffff80886e95 in hpet_intr_single (arg=0xfffffe00a3faa0b0)
    at ../../../sys/dev/acpica/acpi_hpet.c:314
#10 0xffffffff805b0dd8 in intr_event_handle (ie=ie@entry=0xfffff800020c1800,
    frame=frame@entry=0xfffffe00084b1d60)
    at ../../../sys/kern/kern_intr.c:1375
#11 0xffffffff808c0420 in intr_execute_handlers (isrc=0xfffff800025fa138,
    frame=0xfffffe00084b1d60) at ../../../sys/x86/x86/intr_machdep.c:357
#12 <signal handler called>
#13 0xffffffff808bcdd5 in cpu_idle_hlt (sbt=<optimized out>)
    at ../../../sys/x86/x86/cpu_machdep.c:246
#14 0xffffffff808bc0b8 in cpu_idle (busy=0)
    at ../../../sys/x86/x86/cpu_machdep.c:685
#15 0xffffffff806157b1 in sched_idletd (dummy=<optimized out>)
    at ../../../sys/kern/sched_ule.c:3018
#16 0xffffffff805ade26 in fork_exit (
    callout=0xffffffff806152d0 <sched_idletd>, arg=0x0,
    frame=0xfffffe00084b1f40) at ../../../sys/kern/kern_fork.c:1094
#17 <signal handler called>
(kgdb)