So there I was having a lovely time doing the seL4 Tutorials...and I got hit with debug output #1 below, so I confirmed that I indeed had nested virtualization working by making an running an Ubuntu VM in side of an Ubuntu VM on an Ubuntu box in using kvm and qemu, so I do not think it is that. I tried passing the host processor through just to see if there something was getting in the way to no avail. That was when I decided to go through the devel archives and the closest similar post I could find was 07 Aug 2020 ( https://sel4.systems/pipermail/devel/2020-August/002845.html) unfortunately there's no debug output so I cannot confirm is it is the same issue. There was also an issue in April ( https://sel4.systems/pipermail/devel/2020-April/002781.html) that also looked similar but I grep'd through the source and could not find the line referenced line from the commit. Finally I natively built minimal from https://github.com/seL4/camkes-vm-examples in the hopes that it was an issue with the tutorial docker container which led to output #2 below. Which brings me to now humbly request for help so I can finish up the tutorials. Thank you advance for any help anyone can provide, hopefully it is a simple mistake on my part. -Jim ====== VERY LONG DEBUG STUFF BELOW ====== - Debug Output #1: ./simulate: qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split -cpu Nehalem,+vme,+pdpe1gb,-xsave,-xsaveopt,-xsavec,-fsgsbase,-invpcid,enforce,+vmx -nographic -serial mon:stdio -m size=2G -enable-kvm -device intel-iommu,intremap=off -net nic,model=e1000 -net tap,script=no,ifname=tap0 -kernel images/kernel-x86_64-pc99 -initrd images/capdl-loader-image-x86_64-pc99 Boot config: debug_port = 0x3f8 Boot config: disable_iommu = false Detected 1 boot module(s): module #0: start=0xa1d000 end=0x1e366e0 size=0x14196e0 name='images/capdl-loader-image-x86_64-pc99' Parsing GRUB physical memory map Physical Memory Region from 0 size 9fc00 type 1 Physical Memory Region from 9fc00 size 400 type 2 Physical Memory Region from f0000 size 10000 type 2 Physical Memory Region from 100000 size 7fedf000 type 1 Adding physical memory region 0x100000-0x7ffdf000 Physical Memory Region from 7ffdf000 size 21000 type 2 Physical Memory Region from b0000000 size 10000000 type 2 Physical Memory Region from fed1c000 size 4000 type 2 Physical Memory Region from feffc000 size 4000 type 2 Physical Memory Region from fffc0000 size 40000 type 2 Multiboot gave us no video information ACPI: RSDP paddr=0xf68d0 ACPI: RSDP vaddr=0xf68d0 ACPI: RSDT paddr=0x7ffe210d ACPI: RSDT vaddr=0x7ffe210d Kernel loaded to: start=0x100000 end=0xa1c000 size=0x91c000 entry=0x10125e ACPI: RSDT paddr=0x7ffe210d ACPI: RSDT vaddr=0x7ffe210d ACPI: FADT paddr=0x7ffe1ee5 ACPI: FADT vaddr=0x7ffe1ee5 ACPI: FADT flags=0x84a5 ACPI: DMAR paddr=0x7ffe20c5 ACPI: DMAR vaddr=0x7ffe20c5 ACPI: IOMMU host address width: 39 ACPI: 1 IOMMUs detected ACPI: MADT paddr=0x7ffe1fd9 ACPI: MADT vaddr=0x7ffe1fd9 ACPI: MADT apic_addr=0xfee00000 ACPI: MADT flags=0x1 ACPI: MADT_APIC apic_id=0x0 ACPI: MADT_IOAPIC ioapic_id=0 ioapic_addr=0xfec00000 gsib=0 ACPI: MADT_ISO bus=0 source=0 gsi=2 flags=0x0 ACPI: MADT_ISO bus=0 source=5 gsi=5 flags=0xd ACPI: MADT_ISO bus=0 source=9 gsi=9 flags=0xd ACPI: MADT_ISO bus=0 source=10 gsi=10 flags=0xd ACPI: MADT_ISO bus=0 source=11 gsi=11 flags=0xd ACPI: 1 CPU(s) detected ELF-loading userland images from boot modules: size=0x289a000 v_entry=0x4083af v_start=0x400000 v_end=0x2c9a000 p_start=0x1e37000 p_end=0x46d1000 Moving loaded userland images to final location: from=0x1e37000 to=0xa1c000 size=0x289a000 Starting node #0 with APIC ID 0 Mapping kernel window is done vt-x: Load IA32_PERF_GLOBAL_CONTROL not supported. Hardware debugging may not work IOMMU 0x0: 16-bit domain IDs supported IOMMU: Using 3 page-table levels (max. supported:3) IOMMU: Create VTD context table for PCI bus 0x0 (pptr=0xffffff807e01d000) ===== SNIP ====== IOMMU: Create VTD context table for PCI bus 0xfe (pptr=0xffffff807e11b000) IOMMU: Create VTD context table for PCI bus 0xff (pptr=0xffffff807e11c000) IOMMU 0x0: enabling... enabled Booting all finished, dropped to user space Single bus detected lib_pci_scan_dev found pci device 0 0 PCI :: 00.00.00 : intel Unknown device ID. (vid 0x8086 did 0x29c0) line0 pin0 lib_pci_scan_dev found pci device 0 1 PCI :: 00.01.00 : Unknown vendor ID. Unknown device ID. (vid 0x1234 did 0x1111) line0 pin0 BAR0 : [ mem 0xfd000000 sz 0x1000000 szmask 0xff000000 prefetch ] BAR2 : [ mem 0xfebb0000 sz 0x1000 szmask 0xfffff000 ] lib_pci_scan_dev found pci device 0 2 PCI :: 00.02.00 : intel Unknown device ID. (vid 0x8086 did 0x100e) line11 pin1 BAR0 : [ mem 0xfeb80000 sz 0x20000 szmask 0xfffe0000 ] BAR1 : [ io 0xc000 sz 0x40 szmask 0xffffffc0 ] lib_pci_scan_dev found pci device 0 31 PCI :: 00.1f.00 : intel intel_ich9_8 (vid 0x8086 did 0x2918) line0 pin0 lib_pci_scan_dev found multi function device 0 31 PCI :: 00.1f.02 : intel Unknown device ID. (vid 0x8086 did 0x2922) line10 pin1 BAR4 : [ io 0xc080 sz 0x20 szmask 0xffffffe0 ] BAR5 : [ mem 0xfebb1000 sz 0x1000 szmask 0xfffff000 ] PCI :: 00.1f.03 : intel intel_ich9_6 (vid 0x8086 did 0x2930) line10 pin1 BAR4 : [ io 0x700 sz 0x40 szmask 0xffffffc0 ] ========== KERNEL EXCEPTION ========== Vector: 0xd ErrCode: 0x0 IP: 0xffffffff8080d2e9 SP: 0xffffffff80a0bd88 FLAGS: 0x10002 CR0: 0x8001003b CR2: 0x0 (page-fault address) CR3: 0xa17000 (page-directory physical address) CR4: 0x2220 Stack Dump: *0xffffffff80a0bd88 == 0xffffff807c052880 *0xffffffff80a0bd90 == 0xffffff80318c1400 *0xffffffff80a0bd98 == 0x1 *0xffffffff80a0bda0 == 0xffffffff80812415 *0xffffffff80a0bda8 == 0xffffff8020001580 *0xffffffff80a0bdb0 == 0x1000ff8029831000 *0xffffffff80a0bdb8 == 0xc *0xffffffff80a0bdc0 == 0xffffffff8081eeb8 *0xffffffff80a0bdc8 == 0xc *0xffffffff80a0bdd0 == 0xffffff8020002560 *0xffffffff80a0bdd8 == 0xffffff8029831000 *0xffffffff80a0bde0 == 0x0 *0xffffffff80a0bde8 == 0x1ffed6 *0xffffffff80a0bdf0 == 0xffffff8029831000 *0xffffffff80a0bdf8 == 0xffffff80318c1c00 *0xffffffff80a0be00 == 0xffffff8020002540 *0xffffffff80a0be08 == 0xffffffff80a0be60 *0xffffffff80a0be10 == 0xffffff8020002540 *0xffffffff80a0be18 == 0xffffff80318c18a0 *0xffffffff80a0be20 == 0xffffff8029831000 Halting... halting... Kernel entry via Syscall, number: 1, Call Cap type: 12, Invocation tag: 54 - Debug Output #2: ===== SNIP: Same as above ===== IOMMU: Create VTD context table for PCI bus 0xff (pptr=0xff10d000) IOMMU 0x0: enabling... enabled Booting all finished, dropped to user space <> Single bus detected lib_pci_scan_dev found pci device 0 0 PCI :: 00.00.00 : intel Unknown device ID. (vid 0x8086 did 0x29c0) line0 pin0 lib_pci_scan_dev found pci device 0 1 PCI :: 00.01.00 : Unknown vendor ID. Unknown device ID. (vid 0x1234 did 0x1111) line0 pin0 BAR0 : [ mem 0xfd000000 sz 0x1000000 szmask 0xff000000 prefetch ] BAR2 : [ mem 0xfebb0000 sz 0x1000 szmask 0xfffff000 ] lib_pci_scan_dev found pci device 0 2 PCI :: 00.02.00 : intel Unknown device ID. (vid 0x8086 did 0x100e) line11 pin1 BAR0 : [ mem 0xfeb80000 sz 0x20000 szmask 0xfffe0000 ] BAR1 : [ io 0xc000 sz 0x40 szmask 0xffffffc0 ] lib_pci_scan_dev found pci device 0 31 PCI :: 00.1f.00 : intel intel_ich9_8 (vid 0x8086 did 0x2918) line0 pin0 lib_pci_scan_dev found multi function device 0 31 PCI :: 00.1f.02 : intel Unknown device ID. (vid 0x8086 did 0x2922) line10 pin1 BAR4 : [ io 0xc080 sz 0x20 szmask 0xffffffe0 ] BAR5 : [ mem 0xfebb1000 sz 0x1000 szmask 0xfffff000 ] PCI :: 00.1f.03 : intel intel_ich9_6 (vid 0x8086 did 0x2930) line10 pin1 BAR4 : [ io 0x700 sz 0x40 szmask 0xffffffc0 ] seL4 failed assertion '(cte_t *)mdb_node_get_mdbNext(destSlot->cteMDBNode) == NULL && (cte_t *)mdb_node_get_mdbPrev(destSlot->cteMDBNode) == NULL' at /home/user/Documents/labs/rr/os/seL4-AUS/camkes_vm_examples/kernel/src/object/cnode.c:428 in function cteInsert halting... Kernel entry via Syscall, number: 1, Call Cap type: 12, Invocation tag: 53