From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: L1[0x1fb] = 0000000000000000 which faults on one type of machine but on another works? Date: Wed, 16 Mar 2011 22:32:16 +0000 Message-ID: References: <20110316221912.GA13035@dumpdata.com> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20110316221912.GA13035@dumpdata.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Konrad Rzeszutek Wilk , xen-devel@lists.xensource.com, gianni.tedesco@citrix.com, andrew.thomas@oracle.com, Jeremy Fitzhardinge , Ian Cc: swente@infinitumb.de List-Id: xen-devel@lists.xenproject.org On 16/03/2011 22:19, "Konrad Rzeszutek Wilk" wrote: > OK, so I've come up a fix that is a back-port of how 2.6.38 does it > which is that it removes the check I mentioned above and in xen_set_fixmap > we set the FIX_APIC_BASE to actually point to a dummy ioapic_mapping. > It is 7cb068cf1ba90425e12f3a7b3caed9d018fa9b8c in for-2.6.32/bug-fixes > > Gianni, you might want to check this out in case it fixes the problem you > are experiencing. > > But one thing I can't understand is why on one machine (IBM x3850) > I get this crash, while another one with the same pagetable contents > (L1 has nothing for 0x1fb) it works just fine? I added a panic and used > the Xen hypervisor kdb to manually inspect the pagetable, and it has > the same contents as the IBM x3850 -but it boots fine with this invalid value. > Any ideas? Could the native_apic_read() come from ACPI DSDT of that particular machine type (x3850)? K.