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From: Mukesh Rathor <mukesh.rathor@oracle.com>
To: Jan Beulich <JBeulich@suse.com>
Cc: xen-devel <xen-devel@lists.xen.org>,
	IanCampbell <Ian.Campbell@citrix.com>,
	"stefano.stabellini@eu.citrix.com"
	<stefano.stabellini@eu.citrix.com>
Subject: Re: [hybrid]: hang in update_wall_time
Date: Wed, 21 Mar 2012 11:08:48 -0700	[thread overview]
Message-ID: <20120321110848.1978c48d@mantra.us.oracle.com> (raw)
In-Reply-To: <4F6859AB0200007800079895@nat28.tlf.novell.com>

On Tue, 20 Mar 2012 09:19:23 +0000
"Jan Beulich" <JBeulich@suse.com> wrote:

> >>> On 20.03.12 at 02:30, Mukesh Rathor <mukesh.rathor@oracle.com>
... 
> Your Dom0 hasn't possibly played with the HPET, and Xen at the same
> time is using the HPET as clock source? (Preventing this is rather
> difficult, as the HPET memory space - iirc - is just 1k, so excluding
> Dom0 access to the full page isn't easily possible. Consequently, Xen
> so far has been relying on Dom0 to not get in the way.)

Pretty close. I debugged it finally, and the problem was the hybrid
writing to the HPET while xen was using it. This was happening because
ACPI was not properly initialized, and created a ripple effect where
hpet_virt_address was set. In PV, it's not set and so hpet_late_init()
bails. 

Anyways, I fixed it, and now to next one caused by proper
initialization of ACPI... :).

thanks,
Mukesh

  reply	other threads:[~2012-03-21 18:08 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-03-20  1:30 [hybrid]: hang in update_wall_time Mukesh Rathor
2012-03-20  9:19 ` Jan Beulich
2012-03-21 18:08   ` Mukesh Rathor [this message]
2012-03-20 12:39 ` Stefano Stabellini
2012-03-20 19:08   ` Mukesh Rathor
2012-03-21 10:42     ` Stefano Stabellini

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