I'm trying to boot FreeBSD-12.1-RELEASE-i386-bootonly.iso inside qemu: $ qemu-system-i386 -enable-kvm -boot d -cdrom FreeBSD-12.1-RELEASE-i386-bootonly.iso -cpu max -display curses To reproduce the fault, both -enable-kvm and '-cpu max' must be used. The host is Gentoo Linux. The CPU is: processor : 0 vendor_id : AuthenticAMD cpu family : 23 model : 113 model name : AMD Ryzen 5 3600 6-Core Processor stepping : 0 microcode : 0x8701021 cpu MHz : 2794.608 cache size : 512 KB physical id : 0 siblings : 12 core id : 0 cpu cores : 6 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 16 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt p dpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 movbe popcn t aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_c ore perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_pstate sme ssbd mba sev ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 cqm rdt_a rdse ed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru wbnoinvd arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif umip rdp id overflow_recov succor smca bugs : sysret_ss_attrs spectre_v1 spectre_v2 spec_store_bypass bogomips : 7190.59 TLB size : 3072 4K pages clflush size : 64 cache_alignment : 64 address sizes : 43 bits physical, 48 bits virtual power management: ts ttp tm hwpstate cpb eff_freq_ro [13] [14] I'm getting: Fatal trap 9: general protection fault while in kernel mode cpuid = 0; apic id = 00 error code = 0 instruction pointer = 0x20:0x157cfe3 stack pointer = 0x28:0x2423bb8 frame pointer = 0x28:0x2423bdc code segment = base rx0, limit 0xfffff, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor eflags = resume, IOPL = 0 current process = 0 () trap number = 9 panic: general protection fault cpuid = 0 time = 1 KDB: stack backtrace: #0 0x103c50e at kdb_backtrace+0x4e #1 0xff6001 at vpanic+0x121 #2 0xff5ed4 at panic+0x14 #3 0x155cf0e at trap_fatal+0x34e #4 0x155c392 at trap+0xd2 #5 0xffc0316d at PTDpde+0x4175 #6 0xf96644 at mi_startup+0xe4 #7 0x8fa05f at btext+0x5f Uptime: 1s I'm going to try installing it without '-cpu max' and then building fresh kernel with debug.
FWICS the issue doesn't happen on master anymore but it does happen on releng/12.1 branch.
Do 12.2-RC images boot?
FreeBSD-12.2-RC3-i386-bootonly.iso fails the same way.
I'm going to try a reverse-bisect.
I've been able to go back as far as to a93b5bbe069508aa0f8973501712d9c3664fc683 (2019-12-06) and reproduce the new (i.e. working) behavior. My next stop ended up to be incompatible with userland, so I'll need to try approaching in the other direction.
Curious enough, 12.0 doesn't seem to suffer from it.