Re: CURRENT (after commit b1f72dd2a9a5e69a310b9e76b55f16cff433b8da): silently crashing when make -jXX buildworld

From: Herbert J. Skuhra <herbert_at_gojira.at>
Date: Sat, 21 Mar 2026 10:58:39 UTC 
On Sat, 21 Mar 2026, at 09:30, A FreeBSD User wrote:
> Hello,
>
> after upgrading sources and recompiling averything from scratch after 
> make cleanworld, host is
> silently rebooting (not trace of a crash or anything suitable to 
> present).
>
> The box is booting as usual, starting jails.
> When issuing "make -j16 buildworld buildkernel", the box shows some 
> text on the console and
> then - byebye. Rebooting, no crashdump.
>
> The same issue occurs when booting in single user mode.
>
>
> Working kernel is
> FreeBSD 16.0-CURRENT #9 main-n284575-14b9955e57cc: Fri Mar 20 05:39:16 
> CET 2026 amd64
>
> anything later/beyond seems to fail on all recent CURRENT running boxes.
>
> Platform is AMD AM5 based toy CPUs.

I guess this is caused by e90950627327de9226b052851b36f341bc72b746.
/var/log/messages shows:
Mar 21 11:38:08 srv03 kernel: Fatal trap 9: general protection fault while in kernel mode
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 syslogd: last message repeated 4 times
Mar 21 11:38:08 srv03 kernel: cpuid = 5; apic id = 05
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 kernel: Fatal trap 9: general protection fault while in kernel mode
Mar 21 11:38:08 srv03 syslogd: last message repeated 1 times
Mar 21 11:38:08 srv03 kernel: cpuid = 12; apic id = 0c
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 syslogd: last message repeated 1 times
Mar 21 11:38:08 srv03 kernel: cpuid = 13; apic id = 0d
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 kernel: Fatal trap 9: general protection fault while in kernel mode
Mar 21 11:38:08 srv03 kernel: instruction pointer       = 0x20:0xffffffff8268b324
Mar 21 11:38:08 srv03 kernel: cpuid = 11; apic id = 0b
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 syslogd: last message repeated 1 times
Mar 21 11:38:08 srv03 kernel: stack pointer             = 0x28:0xfffffe01d249a6c0
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 syslogd: last message repeated 1 times
Mar 21 11:38:08 srv03 kernel: instruction pointer       = 0x20:0xffffffff8110df0b
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 syslogd: last message repeated 1 times
Mar 21 11:38:08 srv03 kernel: Fatal trap 12: page fault while in kernel mode
Mar 21 11:38:08 srv03 kernel: 
Mar 21 11:38:08 srv03 kernel: cpuid = 15; apic id = 0f
Mar 21 11:38:08 srv03 kernel: fault virtual address     = 0xffffffff0507f098
Mar 21 11:38:08 srv03 kernel: Fatal trap 12: page fault while in kernel mode
Mar 21 11:38:08 srv03 kernel: fault code                = supervisor read data, page not present
Mar 21 11:38:08 srv03 kernel: cpuid = 6; apic id = 06
Mar 21 11:38:08 srv03 kernel: fault virtual address     = 0x0
Mar 21 11:38:08 srv03 kernel: fault code                = supervisor read data, page not present
Mar 21 11:38:08 srv03 kernel: instruction pointer       = 0x20:0xffffffff80bb0aa4
Mar 21 11:38:08 srv03 kernel: stack pointer             = 0:0xfffffe01d2305300
Mar 21 11:38:08 srv03 kernel: frame pointer             = 0:0xfffffe01d2305320
Mar 21 11:38:08 srv03 kernel: code segment              = base 0x0, limit 0xfffff, type 0x1b
Mar 21 11:38:08 srv03 kernel:                   = DPL 0, pres 1, long 1, def32 0, gran 1
Mar 21 11:38:08 srv03 kernel: processor eflags  = interrupt enabled, resume, Fatal trap 12: page fault while in kernel mode
Mar 21 11:38:08 srv03 kernel: IOPL = 0
Mar 21 11:38:08 srv03 kernel: cpuid = 18; apic id = 12
Mar 21 11:38:08 srv03 kernel: fault virtual address     = 0x20
Mar 21 11:38:08 srv03 kernel: fault code                = supervisor read data, page not present
Mar 21 11:38:08 srv03 kernel: instruction pointer       = 0x20:0xffffffff8110018a
Mar 21 11:38:08 srv03 kernel: stack pointer             = 0x28:0xfffffe01d24ccc00
Mar 21 11:38:08 srv03 kernel: frame pointer             = 0x28:0xfffffe01d24ccc20
Mar 21 11:38:08 srv03 kernel: code segment              = base 0x0, limit 0xfffff, type 0x1b
Mar 21 11:38:08 srv03 kernel: current process           = 61681 (which)
Mar 21 11:38:08 srv03 kernel: ---<<BOOT>>---