Re: [gentoo-user] Kernel parameters for VirtualBox

[Peter Humphrey]

On Thursday 18 February 2016 11:23:42 I wrote:
> On Thursday 18 February 2016 11:51:19 J. Roeleveld wrote:
> > On Thursday, February 18, 2016 10:06:25 AM Peter Humphrey wrote:
> --->8
>
> > > I still can't shake the idea that I don't have my kernel set up right.
> > > Do
> > > I
> > > need anything particular in control groups, or name spaces, or anything?
> >
> > About the kernel: I don't have anything special.
> >
> > USE-flags:
> >
> > [I] app-emulation/virtualbox
> >
> >      Installed versions:  4.3.32{tbz2}(03:46:09 PM 11/25/2015)(additions
> >
> > alsa extensions java opengl pam pulseaudio qt4 sdk udev -doc -headless
> > -libressl - python -vboxwebsrv -vnc ELIBC="-FreeBSD"
> > PYTHON_TARGETS="python2_7")
>
> My USE flags:
>
>      Installed versions:  4.3.32{tbz2}(10:25:28 18/02/16)(additions alsa
> extensions opengl pam qt4 sdk udev -doc -headless -java -libressl
> -pulseaudio -python -vboxwebsrv -vnc ELIBC="-FreeBSD"
> PYTHON_TARGETS="python2_7")
>
> I don't have pulseaudio here, but do I need java for virtualbox?
>
> > What does " dmesg " have to say?
> >
> > For me:
> > % dmesg | grep -i vbox
> > [  165.950507] vboxdrv: Found 8 processor cores.
> > [  165.950787] vboxdrv: fAsync=0 offMin=0x1fe offMax=0xa4f9
> > [  165.950828] vboxdrv: TSC mode is 'synchronous', kernel timer mode is
> > 'normal'.
> > [  165.950829] vboxdrv: Successfully loaded version 4.3.32 (interface
> > 0x001a000b).
> > [  165.978641] vboxpci: pci-stub module not available, cannot detach PCI
> > devices
> > [  165.978643] vboxpci: IOMMU found
>
> $ dmesg | grep -i vbox
> [    4.163645] vboxdrv: Found 4 processor cores.
> [    4.163748] vboxdrv: fAsync=0 offMin=0x1d8 offMax=0xd44
> [    4.163792] vboxdrv: TSC mode is 'synchronous', kernel timer mode is
> 'normal'.
> [    4.163793] vboxdrv: Successfully loaded version 4.3.32 (interface
> 0x001a000b).
> [    4.173458] vboxpci: pci-stub module not available, cannot detach PCI
> devices
> [    4.173461] vboxpci: IOMMU not found (not registered)
>
> That last one is suspicious, presumably connected with this:
>
> $ dmesg | grep IOMMU
> [    0.119875] dmar: IOMMU: failed to map dmar0
> [    4.173461] vboxpci: IOMMU not found (not registered)
>
> I wonder what dmar0 is.

While exploring that, I found advice to add iommu=soft to the kernel options. 
Then I got this:

# dmesg | grep -i dmar
[    0.000000] ACPI: DMAR 0x00000000BFE880C0 000090 (v01 AMI    OEMDMAR  
00000001 MSFT 00000097)
[    0.119714] dmar: Host address width 36
[    0.119873] dmar: DRHD base: 0x000000fed90000 flags: 0x1
[    0.120202] WARNING: CPU: 0 PID: 1 at drivers/iommu/dmar.c:829 
warn_invalid_dmar+0x7c/0x90()
[    0.120481] Your BIOS is broken; DMAR reported at address fed90000 returns 
all ones!
[    0.123772]  [<ffffffff813f12bc>] warn_invalid_dmar+0x7c/0x90
[    0.123934]  [<ffffffff813f2549>] dmar_parse_one_drhd+0x4f9/0x550
[    0.124096]  [<ffffffff813f1129>] dmar_walk_remapping_entries+0x29/0x140
[    0.124260]  [<ffffffff81907be6>] dmar_table_init+0xb9/0x138
[    0.124421]  [<ffffffff813f2050>] ? dmar_free_dev_scope+0xb0/0xb0
[    0.124918]  [<ffffffff813f12d0>] ? warn_invalid_dmar+0x90/0x90
[    0.127042] dmar: IOMMU: failed to map dmar0
[    0.127201] dmar: parse DMAR table failure.

Without that kernel option:

[    0.000000] ACPI: DMAR 0x00000000BFE880C0 000090 (v01 AMI    OEMDMAR  
00000001 MSFT 00000097)
[    0.000000] WARNING: CPU: 0 PID: 0 at drivers/iommu/dmar.c:829 
warn_invalid_dmar+0x7c/0x90()
[    0.000000] Your BIOS is broken; DMAR reported at address fed90000 returns 
all ones!
[    0.000000]  [<ffffffff813f12bc>] warn_invalid_dmar+0x7c/0x90
[    0.000000]  [<ffffffff815749a0>] dmar_validate_one_drhd+0xb0/0xf0
[    0.000000]  [<ffffffff813f1129>] dmar_walk_remapping_entries+0x29/0x140
[    0.120132] dmar: Host address width 36
[    0.120291] dmar: DRHD base: 0x000000fed90000 flags: 0x1
[    0.120472] dmar: IOMMU: failed to map dmar0
[    0.120631] dmar: parse DMAR table failure.

So all the kernel option adds is some extra debug info. ATLAS@home still can't 
communicate with VirtualBox.

Now that I think about it, I did update the AMI BIOS several weeks ago. It 
went from 1102 to 2101 - a bit of a step. Maybe that's what's broken my system 
- well, this bit of it, anyway.

> > How exactly are you starting the VMs?
> >
> > I do it all with the GUI: /usr/bin/VirtualBox
>
> Me too, with no problems, but one BOINC project I use includes a .vdi which
> it submits to virtualbox as a guest. That's what's failing. I want to make
> sure virtualbox is set up right before going after that.

-- 
Rgds
Peter