Bug 358591

Summary:	Missing TLB flush with SVM ASIDs
Product:	Red Hat Enterprise Linux 5	Reporter:	Markus Armbruster <armbru>
Component:	kernel-xen	Assignee:	Xen Maintainance List <xen-maint>
Status:	CLOSED ERRATA	QA Contact:	Martin Jenner <mjenner>
Severity:	low	Docs Contact:
Priority:	low
Version:	5.1
Target Milestone:	---
Target Release:	---
Hardware:	x86_64
OS:	Linux
URL:	http://lists.xensource.com/archives/html/xen-devel/2007-10/msg01003.html
Whiteboard:
Fixed In Version:	RHBA-2008-0314	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2008-05-21 14:59:35 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	318891
Bug Blocks:

Description Markus Armbruster 2007-10-30 17:06:17 UTC

Found on xen-devel (see URL), not sure whether we need it, see URL field for
patch.  Quote from there:

But, with SVM ASIDs, it is possible to:
(1) Update CR3 update,
(2) vmenter the guest, and
(3) and vmexit due to a page fault
all without an intervening host TLB flush.

Then the page fault code could use the linear pagetable
to read a top-level shadow page table entry.

But, without this change, it would fetch the wrong value
due to a stale TLB.

Comment 1 Markus Armbruster 2007-10-31 07:55:03 UTC

Fixed in xen-3.1-testing.hg cset 15491:3ce0fb37cf59

Comment 2 Bill Burns 2008-01-03 14:11:11 UTC

This issue was fixed by the rebase to the Xen 3.1.2 Hypervisor and is thus
fixed for RHEL 5.2. Setting flags and state.

Comment 3 Don Zickus 2008-01-24 16:34:47 UTC

You can download this test kernel from http://people.redhat.com/dzickus/el5

Comment 6 errata-xmlrpc 2008-05-21 14:59:35 UTC

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2008-0314.html