Hello, Am 16.04.2024 um 01:31 schrieb Michael Kelley:
Can you give me details of the Hyper-V VM configuration? Maybe a screenshot of the Hyper-V Manager "Settings" for the VM would be a good starting point, though some of the details are on sub-panels in the UI.
It used to be possible to export Hyper-V VM settings as XML, but apparently that option has been removed in Win2016/Win10, in favor of their own proprietary binary .vmcx format... Also, maybe it matters what else Hyper-V is doing. I've installed both WSL and WSA, and Windows Defender is using Core Isolation Memory Integrity. I have also enabled support for nested virtualisation in the Host/Network Switch, but not in that VM. Anyway, I just created two new VMs (one of each generation) with no hard disk and everything else default, added a DVD drive to the SCSI controller of Gen2 (which Gen1 already had on its IDE controller), disabled Secure Boot on Gen2 and added a second vCPU to Gen1 (which Gen2 already had). Afterwards, Gen2's dmidecode looks like the summary you posted, and Gen1 reproduces the issue.
I'm guessing your 32-bit Linux VM is a Generation 1 VM. FWIW, my example was a Generation 2 VM.
Very interesting that Gen2 boots 32-bit Linux better than Gen1 (there is a delay during hardware autoconfigruation (systemd-udevd) for about 30 seconds when booting Gen2 which I did not investigate yet), despite the documentation claiming not to use Gen2 for any 32-bit Host OSes. So I assume this only applies to crappy OSes that directly couple their bitness to the bitness of the UEFI firmware. To be fair, the live media I'm using uses Grub's "non-compliant" Linux loader that bypasses the kernel's EFI stub. When trying with Grub's "linuxefi" loader, Linux does not boot either, as expected. (On the Gen1 VM, the panic happens regardless whether I use grub's linux16 or linux loader, and also with SYSLINUX/ISOLINUX loader).
When you ran a 64-bit Linux and did not have the problem, was that with exactly the same Hyper-V VM configuration, or a different config?
All my tests were performed with a single (Gen1) VM, and the only setting I changed was the number of vCPUs. Regards, Michael
