Bug 141529 - gdb on kernel module generates Dwarf Error
Summary: gdb on kernel module generates Dwarf Error
Keywords:
Status: CLOSED NEXTRELEASE
Alias: None
Product: Red Hat Enterprise Linux 4
Classification: Red Hat
Component: gdb
Version: 4.0
Hardware: ia64
OS: Linux
medium
medium
Target Milestone: ---
: ---
Assignee: Elena Zannoni
QA Contact: David Lawrence
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2004-12-01 20:08 UTC by Dave Anderson
Modified: 2007-11-30 22:07 UTC (History)
0 users

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2004-12-06 20:53:04 UTC
Target Upstream Version:
Embargoed:


Attachments (Terms of Use)

Description Dave Anderson 2004-12-01 20:08:59 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030611

Description of problem:

This problem was originally seen when using the crash utility,
(which has gdb embedded), when trying to do an "add-symbol-file"
operation on a RHEL4 kernel module.

However, the problem can easily be reproduced by simply running
gdb standalone on the kernel module file, which must have its
associated debuginfo file installed on the target system.

In the example below, the RHEL4 exportfs.ko kernel module causes gdb
to generate a "Dwarf Error: Could not find abbrev number 7218" error
message during initialization.





Version-Release number of selected component (if applicable):
gdb-6.1post-1.20040607.43

How reproducible:
Always

Steps to Reproduce:
1. On a system running RHEL4, determine the version with "uname -r",
and if not already installed, install the associated kernel debuginfo
package.
2. cd /lib/modules/`uname -r`/kernel/fs/exportfs
3. gdb exportfs.ko
    

Actual Results:  
# gdb ./fs/exportfs/exportfs.ko
GNU gdb Red Hat Linux (6.1post-1.20040607.43rh)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and
you are welcome to change it and/or distribute copies of it under
certain conditions. Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for
details. This GDB was configured as "ia64-redhat-linux-gnu"...
Dwarf Error: Could not find abbrev number 7218 [in module
/usr/lib/debug/lib/modules/2.6.9-1.648_EL.netdump/kernel/fs/exportfs/exportfs.ko.debug]

(gdb)


Expected Results:  
Should initialize with no errors. 

Additional info:

Comment 1 Dave Anderson 2004-12-06 20:53:04 UTC
This report was based upon the exportfs.ko module from the
2.6.9-1.648_EL kernel, which was compiled with:

  (gcc version 3.4.2 20041017 (Red Hat 3.4.2-6.fc3))

Running the same test on the exportfs.ko module from
the 2.6.9-1.860_EL kernel, which was compiled with:
  
  (gcc version 3.4.3 20041125 (Red Hat 3.4.3-6.EL4))

the error message is no longer exhibited.



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