Re: xen-backend

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

Jean-Yves Migeon wrote:
> Christoph Egger wrote:
> > I identified the debug printf's that make it work. See attached diff.
> > Commenting out one of them or both results in *xenbus_create not being 
> > called and produces a "Hotplug scripts not working" error.
> >
> > A comparison of the assembler snippet in xenbus_probe_init:
> >
> > [assembly]
> >
> > Anyone seeing the impact ?
> Well, I do not see anything suspicious in this assembly? I am perhaps 
> missing something?
>
> Question though: does it fix the bug (*xenbus_create not being called) 
> only by using these printf's, or replacing them with some 
> DELAY(whatever), __insn_barrier() or x86_lfence() has any effect?

__insn_barrier() and x86_mfence() have no effect at all on both printf's.

Both printf's can be replaced with DELAY(31), where 31 is the lowest
possible number. 30 and lower values don't work.

Christoph