Bug 795813 - Bad handling of cfa unwind rules in systemtap runtime unwinder
Summary: Bad handling of cfa unwind rules in systemtap runtime unwinder
Keywords:
Status: CLOSED DUPLICATE of bug 796328
Alias: None
Product: Red Hat Enterprise Linux 6
Classification: Red Hat
Component: systemtap
Version: 6.3
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: rc
: ---
Assignee: Frank Ch. Eigler
QA Contact: qe-baseos-tools-bugs
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2012-02-21 15:32 UTC by Mark Wielaard
Modified: 2012-02-22 17:20 UTC (History)
3 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2012-02-22 17:20:36 UTC
Target Upstream Version:

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Description Mark Wielaard 2012-02-21 15:32:17 UTC 
Description of problem:

A sequence of DW_CFA_def_expression followed by a DW_CFA_def_cfa which sets a register rule could make the systemtap runtime unwinder

Version-Release number of selected component (if applicable):

systemtap-1.6-4.el6.x86_64

How reproducible:

Not very. Would take deliberate action to create such a cfa unwind rule. Current rhel6 kernels don't contain any. But fedora kernels do. So the upstream reproducer doesn't currently work. But t would be good to fix in case such sequences do pop up in the future or if user space contains such rules.

Additional info:

Patch attached to upstream bug and already in upstream git. Should not be hard to apply to current rhel systemtap sources.
Comment 4 Vincent Danen 2012-02-22 17:20:36 UTC 

*** This bug has been marked as a duplicate of bug 796328 ***
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