Re: [PATCH hurd] rumpdisk: Include complete USB stack to enable mass storage driver

[Damien Zammit]

Hi Samuel,

On 26/6/23 02:41, Samuel Thibault wrote:
>> This simple change allows hurd to be bootable off usb!
> 
> Well, yes and no :)
> 
> We also need /dev entries. It happens that this re-uses /dev/sd*
> names, so we need to care about compatibility. We probably want
> rumpdisk_device_open to forward to the kernel when 'disabled' is true.
  
OK

>> It is not ideal to have entire usb stack with the mass storage driver
>> and combined with SATA, but there is no easy way to separate
>> the usb stack into host/device yet.
> 
> Ok, but can't we build a separate rumpusbdisk that only has the USB
> drivers? Each process (SATA+IDE and USB) can easily drive its own PCI
> card.
  
Yes that is certainly possible, I can work on that next.

>> Caveats: USB seems to share IRQs with network device,
>> which does not seem to work well currently.
>> I am not sure of the status of irq sharing but it seems broken.
> 
> That was supposed to be working, but evil lies in the details as usual.
> 

I have a feeling that ACPI provides a list of possible IRQs per device
and it's up to the host to figure out a set of unconflicting configurations
and to set them using _SRS methods.

Where can I find this info?

Damien