WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] Re: pv_ops parport trouble

To: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Re: pv_ops parport trouble
From: Jeremy Fitzhardinge <jeremy@xxxxxxxx>
Date: Thu, 19 Feb 2009 08:23:43 -0800
Cc: Xen Development Mailing List <xen-devel@xxxxxxxxxxxxxxxxxxx>, Gerd Hoffmann <kraxel@xxxxxxxxxx>
Delivery-date: Thu, 19 Feb 2009 08:24:09 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <C5C33459.314B%keir.fraser@xxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <C5C33459.314B%keir.fraser@xxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Thunderbird 2.0.0.19 (X11/20090105)
Keir Fraser wrote:
On 19/02/2009 15:28, "Gerd Hoffmann" <kraxel@xxxxxxxxxx> wrote:

Note that IRQ 7 is *level* triggered and we have a bunch of *shared*
irqs which are *edge* triggered.  Given this I wonder my test box is
able to stay up that long.

Yes, that looks completely backwards. Could pv_ops dom0 be getting the
trigger flag in IO-APIC redir entries inverted somehow?

I guess that's possible, but the code in question does just pass the trigger and polarity straight through. What does it say about the trigger and polarity for those interrupts in the dmesg output?

I guess it would explain quite a few of the "lost interrupt" symptoms we've been seeing, but I'm surprised things work at all well if they really are reversed.

   J

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel