[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]
Re: port-amd64/49150: xrstor is privileged in Xen
The following reply was made to PR port-amd64/49150; it has been noted by GNATS.
From: David Laight <david%l8s.co.uk@localhost>
Subject: Re: port-amd64/49150: xrstor is privileged in Xen
Date: Thu, 11 Sep 2014 21:26:43 +0100
On Mon, Aug 25, 2014 at 05:25:00AM +0000,
> >Number: 49150
> >Category: port-amd64
> >Synopsis: xrstor instruction is privileged in Xen
> >Confidential: no
> >Severity: critical
> >Priority: high
> >Responsible: port-amd64-maintainer
> >State: open
> >Class: sw-bug
> >Submitter-Id: net
> >Arrival-Date: Mon Aug 25 05:25:00 +0000 2014
> >Originator: John Nemeth
> >Release: NetBSD 7.0 BETA and -current of same time frame
> The xrstor instruction is privileged in Xen and the use of
> it leads to a panic, "fatal privileged instruction fault in supervisor
> Attempt to boot a NetBSD 7 BETA domu kernel and watch it go
> boom at mountroot time.
ISTR this is in 'fpu' setup deecting avx??
IIRC the kernel only calls xrstor instruction if one of the other
registers says it is available.
So xen is failing to lie....
Possibly the instruction needs a 'trap detect' added and to disable avx
if it faults.
David Laight: david%l8s.co.uk@localhost
Main Index |
Thread Index |