Re: Event delivery and "domain blocking" on PVHv2

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Fri, Jun 19, 2020 at 12:28:50PM +0200, Martin Lucina wrote:
> On 2020-06-18 13:46, Roger Pau Monné wrote:
> > On Thu, Jun 18, 2020 at 12:13:30PM +0200, Martin Lucina wrote:
> > > At this point I don't really have a clear idea of how to progress,
> > > comparing my implementation side-by-side with the original PV
> > > Mini-OS-based
> > > implementation doesn't show up any differences I can see.
> > > 
> > > AFAICT the OCaml code I've also not changed in any material way, and
> > > that
> > > has been running in production on PV for years, so I'd be inclined
> > > to think
> > > the problem is in my reimplementation of the C parts, but where...?
> > 
> > A good start would be to print the ISR and IRR lapic registers when
> > blocked, to assert there are no pending vectors there.
> > 
> > Can you apply the following patch to your Xen, rebuild and check the
> > output of the 'l' debug key?
> > 
> > Also add the output of the 'v' key.
> 
> Had to fight the Xen Debian packages a bit as I wanted to patch the exact
> same Xen (there are some failures when building on a system that has Xen
> installed due to following symlinks when fixing shebangs).
> 
> Here you go, when stuck during netfront setup, after allocating its event
> channel, presumably waiting on Xenstore:
> 
> 'e':
> 
> (XEN) Event channel information for domain 3:
> (XEN) Polling vCPUs: {}
> (XEN)     port [p/m/s]
> (XEN)        1 [1/0/1]: s=3 n=0 x=0 d=0 p=33
> (XEN)        2 [1/1/1]: s=3 n=0 x=0 d=0 p=34
> (XEN)        3 [1/0/1]: s=5 n=0 x=0 v=0
> (XEN)        4 [0/1/1]: s=2 n=0 x=0 d=0
> 
> 'l':
> 
> (XEN) d3v0 IRR:
> ffff8301732dc200b
> (XEN) d3v0 ISR:
> ffff8301732dc100b

Which version of Xen is this? AFAICT it doesn't have the support to
print a bitmap.

Do you think you could also pick commit
8cd9500958d818e3deabdd0d4164ea6fe1623d7c [0] and rebuild? (and print
the info again).

Thanks, Roger.

[0] 
http://xenbits.xen.org/gitweb/?p=xen.git;a=patch;h=8cd9500958d818e3deabdd0d4164ea6fe1623d7c