Re: Hurd rumpdisk on real hardware

[João Pedro Malhado <phlogiston@sapo.pt>]

Hello Mike,

On Wed, Sep 17, 2025 at 07:43:21PM +0100, Michael Kelly wrote:
> > On Mon, Sep 08, 2025 at 08:54:44PM +0100, Michael Kelly wrote:
> > > I built an ext2fs disk image of hurd-i386 using mmdebstrap which when dd'd
> > > onto a partition using Qemu works normally.  The same image on the netbook
> > > gets as far as reporting the disk geometry and capabilities correctly but
> > > the boot log reports nothing further. Running a gnumach compiled with
> > > --disable-linux-groups (is this valid on i386?) results in further progress
> > > but only to report a number of lost interrupts of the form:
> > > 
> > > piixide0:0:0 interrupt lost
> > > 
> > > [.....] type ata tc_bcount: 4096 tc_skip: 0
> In this a particular case, it seems that I failed a golden rule in computing
> generally to "never make assumptions". I had spent some time on another 64
> bit system whose difficulties do indeed seem to be hardware related (Note
> "seem to" being a get out clause!) and then this 32 bit machine also
> reporting errors including interrupts led me to believe hardware issues were
> the cause. In actual fact, restoring the official gnumach image and looking
> properly I could see that the problem was nothing to do with specific
> hardware but just the total RAM available being 1Gb. I'll report on this
> issue separately to avoid polluting this thread.

I read the other thread, but I'm unsure about the hypothesis that these errors
are related to the low amount of RAM. On my Toshiba netbook where rumpdisk is
failing with similar errors to what you are seeing, I indeed also have 1Gb of
RAM. But on my HP laptop where rumpdisk works fine I have 512Mb.
If this is memory related, there must be something weird going on with RAM
segmentation. I'm attaching gnumach's dmesg in case anyone is able to make sense
of it.

Regards,
João

GNU Mach 1.8+git20250731-up-486
biosmem: physical memory map:
biosmem: 000000000000000000:00000000000009f000, available
biosmem: 00000000000009fc00:0000000000000a0000, reserved
biosmem: 0000000000000e0000:000000000000100000, reserved
biosmem: 000000000000100000:00000000001f7d0000, available
biosmem: 00000000001f7d0000:00000000001f7efc00, reserved
biosmem: 00000000001f7f0000:00000000001f7fb000, ACPI NVS
biosmem: 00000000001f7fb000:00000000001f800000, reserved
biosmem: 0000000000e0000000:0000000000f0000000, reserved
biosmem: 0000000000fec00000:0000000000fec02000, reserved
biosmem: 0000000000fed20000:0000000000fed9b000, reserved
biosmem: 0000000000feda0000:0000000000fedc0000, reserved
biosmem: 0000000000ffb00000:0000000000ffc00000, reserved
biosmem: 0000000000fff00000:000000000100000000, reserved
vm_page: page table size: 128960 entries (5544k)
vm_page: DMA: pages: 4080 (15M), free: 0 (0M)
vm_page: DMA: min:500 low:600 high:1000
vm_page: DIRECTMAP: pages: 124880 (487M), free: 120001 (468M)
vm_page: DIRECTMAP: min:6244 low:7492 high:12488
-486
biosmem: physical memory map:
biosmem: 000000000000000000:00000000000009f000, available
biosmem: 00000000000009fc00:0000000000000a0000, reserved
biosmem: 0000000000000e0000:000000000000100000, reserved
biosmem: 000000000000100000:00000000001f7d0000, available
biosmem: 00000000001f7d0000:00000000001f7efc00, reserved
biosmem: 00000000001f7f0000:00000000001f7fb000, ACPI NVS
biosmem: 00000000001f7fb000:00000000001f800000, reserved
biosmem: 0000000000e0000000:0000000000f0000000, reserved
biosmem: 0000000000fec00000:0000000000fec02000, reserved
biosmem: 0000000000fed20000:0000000000fed9b000, reserved
biosmem: 0000000000feda0000:0000000000fedc0000, reserved
biosmem: 0000000000ffb00000:0000000000ffc00000, reserved
biosmem: 0000000000fff00000:000000000100000000, reserved
vm_page: page table size: 128960 entries (5544k)
vm_page: DMA: pages: 4080 (15M), free: 0 (0M)
vm_page: DMA: min:500 low:600 high:1000
vm_page: DIRECTMAP: pages: 124880 (487M), free: 120001 (468M)
vm_page: DIRECTMAP: min:6244 low:7492 high:12488
pcibios_init : BIOS32 Service Directory structure at 0xfa000
pcibios_init : BIOS32 Service Directory entry at 0xf0000
pcibios_init : PCI BIOS revision 2.10 entry at 0xf0322
Probing PCI hardware.
Floppy drive(s): fd0 is 1.44M
floppy0: no floppy controllers found

probing scsi 0/16: advansys 
probing scsi 1/16: BusLogic 
probing scsi 2/16: UltraStor 14F/34F rev. 4.33.00  
probing scsi 3/16: UltraStor 14F/24F/34F 
probing scsi 4/16: Adaptec 152x SCSI driver; $Revision: 1.1 $ 
probing scsi 5/16: Adaptec 174x (EISA) 
probing scsi 6/16:  
probing scsi 7/16: Always IN2000 
probing scsi 8/16:  
probing scsi 9/16:  
probing scsi 10/16:  
probing scsi 11/16: Trantor T128/T128F/T228 
probing scsi 12/16: DTC 3180/3280  
probing scsi 13/16: Tekram DC390(T) V1.11 Feb-05-1997 
probing scsi 14/16:  
probing scsi 15/16: ncr53c8xx - revision 2.5f.1 
done
scsi : 0 hosts.
scsi : detected total.
com 2 out of range
RTC time is 2025-09-18 08:19:10
module 0: pci-arbiter --host-priv-port=${host-port} --device-master-port=${device-port} --next-task=${acpi-task} $(pci-task=task-create) $(task-resume)
module 1: acpi --next-task=${disk-task} $(acpi-task=task-create)
module 2: rumpdisk --next-task=${fs-task} $(disk-task=task-create)
module 3: ext2fs --multiboot-command-line=${kernel-command-line} --exec-server-task=${exec-task} -T typed ${root} $(fs-task=task-create)
module 4: exec $(exec-task=task-create)
5 multiboot modules
task loaded: pci-arbiter --host-priv-port