Red Hat Bugzilla – Bug 243555
utrace: Failing PTRACE_DETACH after ATTACH+CONT(SIGSTOP)
Last modified: 2007-11-30 17:07:44 EST
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.
Created attachment 156655 [details] Testcase
This is a regression and will be fixed in the 5.1 utrace update.
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.
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.
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.
in kernel-2.6.18-30.el5
verified that the testcase does not abort with the -37 kernel.
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 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
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