Bug 117972 - signal backtrace broken
Summary: signal backtrace broken
Status: CLOSED CURRENTRELEASE
Alias: None
Product: Red Hat Enterprise Linux 3
Classification: Red Hat
Component: gdb
Version: 3.0
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Jan Kratochvil
QA Contact: David Lawrence
URL:
Whiteboard:
Keywords:
: 85247 85309 117028 121656 (view as bug list)
Depends On: 126089 126095 133782 133794 133799 136891
Blocks: 125157 170417
TreeView+ depends on / blocked
 
Reported: 2004-03-10 17:07 UTC by Andrew Cagney
Modified: 2007-11-30 22:07 UTC (History)
7 users (show)

(edit)
Clone Of:
(edit)
Last Closed: 2007-01-18 16:13:37 UTC


Attachments (Terms of Use)

Description Andrew Cagney 2004-03-10 17:07:33 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; NetBSD macppc; en-GB; rv:1.4.1)
Gecko/20040217

Description of problem:


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


How reproducible:
Always

Steps to Reproduce:
1.set a breakpoint in a signal handler
2.run to the signal handler
3.do a backtrace
    

Actual Results:  (gdb) break handler
Breakpoint 1 at 0x10000470: file /tmp/segv.c, line 9.
(gdb) run
Starting program: /tmp/segv.32 

Program received signal SIGSEGV, Segmentation fault.
0x00000000 in ?? ()
(gdb) signal SIGSEGV
Continuing with signal SIGSEGV.

Breakpoint 1, handler (sig=11, info=0xffffe390, context=0x100004f4)
    at /tmp/segv.c:9
warning: Source file is more recent than executable.

9         exit (0);
(gdb) bt
#0  handler (sig=11, info=0xffffe390, context=0x100004f4) at /tmp/segv.c:9
#1  <signal handler called>
Cannot access memory at address 0xffffe430
(gdb) 


Additional info:

#include <stdio.h>
#include <signal.h>
#include <ucontext.h>

#ifdef SA_SIGINFO
static void
handler (int sig, siginfo_t *info, ucontext_t *context)
{
  exit (0);
}
#else
static void
handler (int sig, int code, struct sigcontext *scp)
{
  exit (0);
}
#endif

static void
segv (void (*f) (void))
{
  f();
}

main ()
{
  static struct sigaction action;
#ifdef SA_SIGINFO
  action.sa_sigaction = handler;
  action.sa_flags |= SA_SIGINFO;
#else
  action.sa_handler = handler;
#endif
  sigaction (SIGSEGV, &action, NULL);
  segv (NULL);
}

Comment 1 Andrew Cagney 2004-03-10 17:09:32 UTC
*** Bug 85247 has been marked as a duplicate of this bug. ***

Comment 2 Andrew Cagney 2004-03-10 17:12:30 UTC
*** Bug 85309 has been marked as a duplicate of this bug. ***

Comment 3 David Lawrence 2004-03-15 18:53:33 UTC
Changing product and version.

Comment 5 Andrew Cagney 2004-03-22 16:18:05 UTC
- None of them handle this alternative signal handler, overhauling
signal handler unwinders to fix.


Comment 6 Andrew Cagney 2004-03-22 16:25:50 UTC
*** Bug 117028 has been marked as a duplicate of this bug. ***

Comment 7 Johan Walles 2004-03-22 16:35:27 UTC
I see this is "Platform: All", but I thought this was fixed on IA64
with the libunwind based gdb?


Comment 8 Andrew Cagney 2004-05-11 00:40:46 UTC
Yes, libunwind fixes the ia64 specific backtrace.  Unfortunatly it
doesn't fix step/finish/return/next when presented with such a stack
:-(  Both architecture specific and generic fixes are needed.


Comment 9 Andrew Cagney 2004-05-11 00:53:12 UTC
*** Bug 121656 has been marked as a duplicate of this bug. ***

Comment 11 Mike Ranweiler 2004-06-07 17:57:29 UTC
hijack summary to mirror for 121656

Comment 20 Johan Walles 2004-08-25 14:41:13 UTC
Can somebody explain to me why most bugs related to this one are
secret?  I fail to see how being unable to walk the stack in gdb can
relate to anything security sensitive, especially bug 121656 that has
been closed as a duplicate of this one.

It's quite annoying that almost every time I get an e-mail about this
bug it says the equivalent of "Something changed but I won't tell you
what, nyah, nyah.".


Comment 22 IBM Bug Proxy 2004-09-02 19:54:42 UTC
----- Additional Comments From manoji@us.ibm.com(prefers email via manjo@austin.ibm.com)  2004-09-02 15:50 -------
*** Bug 8850 has been marked as a duplicate of this bug. *** 

Comment 27 Johan Walles 2005-02-14 09:24:18 UTC
This bug is NEEDINFO, but I cannot find any request for more info.  Is
any information needed, and if so, what, or has the Status just not
been updated?


Comment 28 IBM Bug Proxy 2005-07-11 19:27:15 UTC
changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|RHEL3_U4                    |RHEL3_U6




------- Additional Comments From corryk@us.ibm.com(prefers email via kevcorry@us.ibm.com)  2005-07-11 15:22 EDT -------
RHEL3-U4 is already out, so moving the target-milestone to RHEL3-U6. 


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