Bug 568153 - ixgbe: stop unmapping DMA buffers too early
Summary: ixgbe: stop unmapping DMA buffers too early
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 5
Classification: Red Hat
Component: kernel
Version: 5.5
Hardware: All
OS: Linux
low
medium
Target Milestone: rc
: 5.5
Assignee: Andy Gospodarek
QA Contact: Red Hat Kernel QE team
URL:
Whiteboard:
: 566597 (view as bug list)
Depends On:
Blocks: 525577 557926 581655
TreeView+ depends on / blocked
 
Reported: 2010-02-24 21:40 UTC by Andy Gospodarek
Modified: 2023-09-14 01:20 UTC (History)
12 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2010-03-30 07:40:27 UTC
Target Upstream Version:
Embargoed:


Attachments (Terms of Use)
ixgbe-fix-early-dma-unmapping-for-devices-using-RSC.patch (3.10 KB, patch)
2010-02-24 21:40 UTC, Andy Gospodarek
no flags Details | Diff


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2010:0178 0 normal SHIPPED_LIVE Important: Red Hat Enterprise Linux 5.5 kernel security and bug fix update 2010-03-29 12:18:21 UTC

Description Andy Gospodarek 2010-02-24 21:40:20 UTC
Created attachment 396164 [details]
ixgbe-fix-early-dma-unmapping-for-devices-using-RSC.patch

Description of problem:

The latest 5.5 kernel will throw the following errors when running a receive stress test with and ixgbe-based device that supports RSC:

DRHD: handling fault status reg 402
DMAR:[DMA Write] Request device [04:00.0] fault addr ffe43000
DMAR:[fault reason 05] PTE Write access is not set
DRHD: handling fault status reg 502
DMAR:[DMA Write] Request device [04:00.0] fault addr fff62000
DMAR:[fault reason 05] PTE Write access is not set
DRHD: handling fault status reg 602
DMAR:[DMA Write] Request device [04:00.0] fault addr ffcf4000
DMAR:[fault reason 05] PTE Write access is not set
DRHD: handling fault status reg 702
DMAR:[DMA Write] Request device [04:00.0] fault addr ffd04000
DMAR:[fault reason 05] PTE Write access is not set
DRHD: handling fault status reg 2
DMAR:[DMA Write] Request device [04:00.0] fault addr ffbeb000
DMAR:[fault reason 05] PTE Write access is not set
DRHD: handling fault status reg 102
DMAR:[DMA Write] Request device [04:00.0] fault addr ff7ac000
DMAR:[fault reason 05] PTE Write access is not set

and performance (throughput) was terrible.  It was determined that buffers were being unmapped too early when using RSC as the first data buffer needed to be left unmapped so it could be modified later.  This attached patch from Intel appears to resolve the issue upstream and in the latest (2.6.18-190.el5) RHEL5.5 development kernels.

Comment 1 Andy Gospodarek 2010-02-24 21:45:05 UTC
From: https://bugzilla.redhat.com/show_bug.cgi?id=525577#c50

"Sibai Li and Greg Rose from Intel LAD have tested Andy's latest kernel [containing the patch attached to bug 568153] for the RSC fix and the problem no longer exists in our tests."

Comment 2 RHEL Program Management 2010-02-24 21:45:37 UTC
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.

Comment 6 John Ronciak 2010-03-02 23:16:36 UTC
Andy, did this make 5.5?  People here are asking.  It looks like as the status is POST but I need to make sure.

Comment 7 Andy Gospodarek 2010-03-03 02:17:10 UTC
John, I feel *quite* confident that it will.

This close to the release bugs will probably remain in POST longer than normal.

Comment 8 Jarod Wilson 2010-03-03 15:45:38 UTC
in kernel-2.6.18-191.el5
You can download this test kernel from http://people.redhat.com/jwilson/el5

Please update the appropriate value in the Verified field
(cf_verified) to indicate this fix has been successfully
verified. Include a comment with verification details.

Comment 12 Chris Ward 2010-03-23 09:34:50 UTC
Any test status updates?

Comment 14 errata-xmlrpc 2010-03-30 07:40:27 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 therefore 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/RHSA-2010-0178.html

Comment 15 Andy Gospodarek 2010-05-25 21:41:01 UTC
*** Bug 566597 has been marked as a duplicate of this bug. ***

Comment 16 Red Hat Bugzilla 2023-09-14 01:20:17 UTC
The needinfo request[s] on this closed bug have been removed as they have been unresolved for 1000 days


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