virtualbox.org

Ever since virtualbox 6.1.28 I have had a hard time booting more than 1 VM at the same time. If I do that then 1 or more of the VMs freeze. So, I revert to version 6.1.26 because that is the last version that let me boot more than 1 VM at the same time. I am asking now because I want to run the latest version. The latest one I ran was 6.1.34 also did the same thing with an error message that I found as a commonality in all the log files that had a VM freeze:
-------------------------------------------------------------------------------
GUI: UIMediumEnumerator: Medium-enumeration finished!
SUP: seg #0: R 0x00000000 LB 0x00001000
SUP: seg #1: R X 0x00001000 LB 0x00109000
SUP: seg #2: R 0x0010a000 LB 0x0004a000
SUP: seg #3: RW 0x00154000 LB 0x00013000
SUP: seg #4: R 0x00167000 LB 0x0000e000
SUP: seg #5: RW 0x00175000 LB 0x00003000
SUP: seg #6: R 0x00178000 LB 0x0000b000
SUP: seg #7: RWX 0x00183000 LB 0x00002000
SUP: seg #8: R 0x00185000 LB 0x00007000
SUP: Loaded VMMR0.r0 (C:\Program Files\Oracle\VirtualBox\VMMR0.r0) at 0xXXXXXXXXXXXXXXXX - ModuleInit at XXXXXXXXXXXXXXXX and ModuleTerm at XXXXXXXXXXXXXXXX using the native ring-0 loader
SUP: VMMR0EntryEx located at XXXXXXXXXXXXXXXX and VMMR0EntryFast at XXXXXXXXXXXXXXXX
SUP: windbg> .reload /f C:\Program Files\Oracle\VirtualBox\VMMR0.r0=0xXXXXXXXXXXXXXXXX
Guest OS type: 'RedHat_64'
fHMForced=true - No raw-mode support in this build!
----------------------------------------------------------------------------
My host had 16GB memory and 6 cores and recently upgraded my memory so it's not a memory capacity problem. My VMs gets 2GB or 4GB RAM depending on the VM and 1 core. Most of my VMs are linux based. I have a Windows 10 21H2 host. Host and guests are x64. I do install the guest additions and I did search before I posted and looked for relevant sections in the manual. I have attached a log and hardening log for my CentOS epel 8-15.el8 VM that freezes. If there is anymore information that you would like to see then I will be more than happy to supply it. Thanks in advance!

You have Hyper-v enabled.

00:00:03.610740 HM: HMR3Init: Attempting fall back to NEM: VT-x is not available
00:00:03.672271 NEM: info: Found optional import WinHvPlatform.dll!WHvQueryGpaRangeDirtyBitmap.
00:00:03.672374 NEM: WHvCapabilityCodeHypervisorPresent is TRUE, so this might work...

See HMR3Init: Attempting fall back to NEM (Hyper-V is active).

Also, make sure to give each VM adequate resources. E.g. most will require 2 cores for useful performance, and with 6 cores total that limits you to two VMs. Your host has plenty of RAM, so give each guest 128MB of graphics RAM.

I will uninstall 6.1.26, install 6.1.34 and disable Hyper-V. I am wondering why is Hyper-V not an issue with 6.1.26 but it is an issue with 6.1.34?

tonytony wrote:why is Hyper-V not an issue with 6.1.26 but it is an issue with 6.1.34?

Windows 11 came out after 6.1.26. The devs started working on using Windows 11 while its Hyper-V was enabled, and it broke a few things for Windows 10 hosts. 6.1.34 still has some of the glitches. The tweaks are ongoing.

Test build 6.1.35 is reported to have a solid fix. If you want to try it, save the test build installer until you update again later.

I just want to report what I tried. I had the problem when I had 6.1.26 and installed 6.1.34. Then I uninstalled 6.1.34 and installed 6.1.26 and everything went back to normal. So, I manually uninstalled 6.1.26 and installed 6.1.34 the result is the same problem. I didn't want to disable Hyper-V just yet.

This time I just installed 6.1.35 (the test build) and to my surprise everything worked normally. Thanks scottgus1. I hope when 6.1.36 comes out everything continues to work again.

tonytony wrote: I hope when 6.1.36 comes out everything continues to work again.

You are not alone in that hope!