Bug 243555

Summary: utrace: Failing PTRACE_DETACH after ATTACH+CONT(SIGSTOP)
Product: Red Hat Enterprise Linux 5 Reporter: Jan Kratochvil <jan.kratochvil>
Component: kernelAssignee: Roland McGrath <roland>
Status: CLOSED ERRATA QA Contact: Martin Jenner <mjenner>
Severity: high Docs Contact:
Priority: high    
Version: 5.0Keywords: Regression
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: RHBA-2007-0959 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2007-11-07 19:52:15 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: 244162    
Bug Blocks: 233852, 233853    
Attachments:
Description Flags
Testcase none

Description Jan Kratochvil 2007-06-09 17:34:21 UTC 
Description of problem:
Developed on upstream the minimal raceless PTRACE_ATTACH method.
It unfortunately fails on UTRACE, I hope it is not a race.

Version-Release number of selected component (if applicable):
kernel-2.6.18-8.1.1.el5.x86_64
kernel-2.6.21-1.3194.fc7
kernel-2.6.20-1.2948.fc6.x86_64

How reproducible:
Always.

Steps to Reproduce:
1. gcc -o cont-sigstop-detach cont-sigstop-detach.c -ggdb2 -Wall
2. ./cont-sigstop-detach 

Actual results:
utrace bug hit
Aborted

Expected results:
[endless run on the upstream linux-2.6.20.4.x86_64]

Additional info:
The code does:
PTRACE_ATTACH
PTRACE_CONT(SIGSTOP)
waitpid() -> SIGSTOP
PTRACE_DETACH -> upstream: 0 vs. utrace: ESRCH

The Bug should be cloned for Fedora if you consider it valid.
Comment 1 Jan Kratochvil 2007-06-09 17:34:21 UTC 
Created attachment 156655 [details]
Testcase
Comment 2 Roland McGrath 2007-06-14 09:11:06 UTC 
This is a regression and will be fixed in the 5.1 utrace update.
Comment 3 RHEL Program Management 2007-06-14 09:24:45 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 4 RHEL Program Management 2007-06-14 09:28:45 UTC 
This bugzilla has Keywords: Regression.  

Since no regressions are allowed between releases, 
it is also being proposed as a blocker for this release.  

Please resolve ASAP.
Comment 6 RHEL Program Management 2007-06-20 12:31:19 UTC 
This request was evaluated by Red Hat Kernel Team for inclusion in a Red
Hat Enterprise Linux maintenance release, and has moved to bugzilla 
status POST.
Comment 9 Don Zickus 2007-07-19 21:21:30 UTC 
in kernel-2.6.18-30.el5
Comment 11 Mike Gahagan 2007-08-03 21:07:19 UTC 
verified that the testcase does not abort with the -37 kernel.
Comment 12 Jan Kratochvil 2007-09-27 18:38:51 UTC 
On kernel-2.6.18-48.el5.x86_64 the testcase from Comment #1 hangs on line 105
(not the original goal of this testcase).
Did not find the other specific utrace Bug affecting it.
Comment 14 Jan Kratochvil 2007-10-28 21:03:25 UTC 
Comment on attachment 156655 [details]
Testcase

Testcase had some racy assertion failures.
Updated testcase is at:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/~checkout~/tests/ptrace-tests/test
s/ptrace-cont-sigstop-detach.c?cvsroot=systemtap
from the testsuite
http://sourceware.org/systemtap/wiki/utrace/tests
It has been verified as FAILing on: kernel-xen-2.6.18-8.1.14.el5.x86_64
Comment 15 errata-xmlrpc 2007-11-07 19:52:15 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-2007-0959.html