Red Hat Bugzilla – Bug 428920
user data corruption on misaligned access with certain FP instructions
Last modified: 2013-08-05 21:43:39 EDT
Description of problem:
Kernel does not correctly handle certain floating point unaligned data traps.
Version-Release number of selected component (if applicable):
All kernel versions ever (do you need separate bugzilla for RHEL4?)
With the right test program and test data - every time
Steps to Reproduce:
1. Run a program that uses "ldf" instruction from an unaligned address, using
update register addressing.
2. Observe register is not adjusted correctly (will always increment by 0x10)
Wrong updated register
Sent patch to Linus ... should be in hi git tree with commit id
1a499150e4ec1299232e24389f648d059ce5617a as soon as he pulls from my tree.
Created attachment 291782 [details]
git commit - has description & patch
Created attachment 292864 [details]
$ tar xzf fptest.tgz
Two "PASS!" lines expected (and you'll get them when running a kernel with
I'm going to assign the bug to me..
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
You can download this test kernel from http://people.redhat.com/dzickus/el5
Don. Grabbed that 2.6.18-77.el5 rpm and installed on my hp zx2000 workstation.
The floating point problem is fixed (my test case passes).
But some other stuff in there doesn't play well with the rest of my system as X
refused to start. I'm running a fairly pure RHEL5 (no updates) ... so maybe
some bits are too old to work with the new kernel?
X server failed to start with 2.6.18-71 on my Hitachi Coldfusion 4s4u..
After reverting patch for bug#240006, the X server works again:
The X server needs to be updated. The changes Luming references in comment #10
and the X server changes were made at the same time. I think somebody (ajax
perhaps) posted the updated X server rpms on people.redhat.com.
I also tried upstream 2.6.23-rc8 , get same problem on the hitachi coldfusion
4s4u. So the patch series should have been upstream for a while...
Doug, could you please point me a link to the page to test the updated X server.
the people.redhat.com/ajax doesn't work.
(In reply to comment #12)
> Doug, could you please point me a link to the page to test the updated X server.
> the people.redhat.com/ajax doesn't work.
The updated X server rpm's can be found here:
but installing xorg-x11-server-Xorg-1.1.1-48.32.el5.ia64.rpm ends up error:
kernel < 2.6.18-60.el5 conflicts with xorg-x11-server-Xorg-1.1.1-48.32.e
Luming, we currently have xorg-x11-server-1.1.1-48.34.el5 in the xorg-x11-server
erratum at http://errata.devel.redhat.com/errata/show/6891. Can you retest with
that package and kernel-2.6.18-77.el5 please?
re-checked the kernel packages, found that the box has multiple kernel packages
installed, some kernel like 2.6.18-53 and 44 are older than 2.6.18-60.el5...
And the rpm installation dependency check seems to require all kernel packages
Now I have installed xorg-x11-server-Xorg-1.1.1-48.32.el5.ia64.rpm , and the X
server works with the kernel-2.6.18-77.el5
hello, what's the latest update of this bug?
hello， where can I get kernel-2.6.18-77.el5? thanks !
Please go to the public beta in the RHN beta channel.
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.