Bug 690597

Summary: systemtap sys/sdt.h probes with semaphore fail on s390
Product: Red Hat Enterprise Linux 6 Reporter: Frank Ch. Eigler <fche>
Component: systemtapAssignee: Josh Stone <jistone>
Status: CLOSED ERRATA QA Contact: qe-baseos-tools-bugs
Severity: unspecified Docs Contact:
Priority: low    
Version: 6.1CC: dmalcolm, fche, mjw, pmuller, psplicha, syeghiay
Target Milestone: rc   
Target Release: ---   
Hardware: s390x   
OS: Unspecified   
Whiteboard:
Fixed In Version: systemtap-1.4-5.el6 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-05-19 13:54:58 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:    
Bug Blocks: 569695    
Attachments:
Description Flags
Find SDT semaphores even in RWX mappings none

Description Frank Ch. Eigler 2011-03-24 18:28:43 UTC 
In bug #569695, it was discovered that python's sys/sdt.h probes were not
being activated with systemtap 1.4 on s390x.  jistone discovered that the
s390x kernel's "noexec" default behaviour is different from other architectures,
and that the systemtap runtime was not turning on the sys/sdt.h semaphores.

A fix is now available in upsteam systemtap, and can be backported into the
rhel6.1 build.  It is a low-risk fix, jistone will comment on testing results
on other architectures.  OTOH it only affects this particular combination of
architecture and uncommon sys/sdt.h usage pattern.  PM etc. may decide whether
to defer to RHEL6.2.
Comment 1 Josh Stone 2011-03-24 20:32:45 UTC 
Created attachment 487423 [details]
Find SDT semaphores even in RWX mappings

This is the upstream commit.  I've confirmed that it fixes the problem discovered in python tests on s390, and the same tests on x86 and x86_64 continue to work.
Comment 5 errata-xmlrpc 2011-05-19 13:54:58 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/RHBA-2011-0651.html