Re: Xenbus issues on Qubes OS / win10

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 23/06/2023 19:50, Rafał Wojdyła wrote:
> On 23 cze 2023 17:37, Rafał Wojdyła wrote:
> > Hello,
> >
> > I'm trying the latest PV drivers on Qubes OS (backend is Xen 4.14.5) 
> > with Windows 10 pro and having some issues. Mainly, xenbus fails to 
> > initialize properly. I've attached a debug output, the main issue 
> > seems to be this:
> > xenbus|StoreAcquire: ====>
> > xenbus|GnttabAcquire: ====>
> > xenbus|RangeSetPop: fail3
> > xenbus|RangeSetPop: fail2
> > xenbus|RangeSetPop: fail1 (c000009a)
> > xenbus|FdoAllocateHole: fail1 (c000009a)
> > xenbus|GnttabAcquire: fail2
> > xenbus|GnttabAcquire: fail1 (c000009a)
> > xenbus|StoreAcquire: fail1 (c000009a)
> > xenbus|FdoD3ToD0: fail6
> >
> > ...which seems pretty suspicious. It's been some years since I looked 
> > at the drivers' code so any ideas as to what may be causing this are 
> > welcome :)
> Followup: in xenbus/gnttab/GnttabAcquire()
>
> status = GrantTableQuerySize(NULL, &Context->MaximumFrameCount);
>
> Context->MaximumFrameCount is 2048 for me, which is bigger than 1 << 
> PAGE_ORDER_2M, which seems to be the limit for FDO memory hole size.
Hmm. Ok - we should probably put something in there to either expand the 
hole, use another one or - probably simpler - query the grant table size 
up-front to correctly size the hole.
  Paul