[Kgdb-bugreport] KGDBOE: "program is no longer writable"

[Santosh S. <san...@gm...>]

Hi All,

Kernel Version : 2.6.30
Arch : x86

I have tried KGDBOE (kgdb over Ethernet) on v2.6.30 from linux-2.6-kgdb.git
jwessel tree. I found that, After hitting the breakpoint, and then saying
continue, console throws the message like " *Cannot remove breakpoints
because program is no longer writable*. " After that, I have to exit from
current gdb session to new gdb session so as to "delete" all the previous
breakpoint and get the console login prompt.

Following is the test log:

Host Side:
========================================================================================
[root@localhost linux-2.6-kgdb]# gdb vmlinux
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html
>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i686-linux-gnu".
For bug reporting instructions, please see:
(gdb) target remote udp:10.161.3.199:6443
warning: The remote protocol may be unreliable over UDP.
Some events may be lost, rendering further debugging impossible.
Remote debugging using udp:10.161.3.199:6443
kgdb_breakpoint () at kernel/kgdb.c:1807
1807            wmb(); /* Sync point after breakpoint */
(gdb) b sys_sync
Breakpoint 1 at 0xc10a7dcd: file fs/sync.c, line 41.
(gdb) c
Continuing.
[New Thread 1415]
[Switching to Thread 1415]
Cannot remove breakpoints because program is no longer writable.
It might be running in another process.
Further execution is probably impossible.

Breakpoint 1, sys_sync () at fs/sync.c:41
41              do_sync(1);
(gdb) c
Continuing.
Cannot remove breakpoints because program is no longer writable.
It might be running in another process.
Further execution is probably impossible.

Breakpoint 1, sys_sync () at fs/sync.c:41
41              do_sync(1);
(gdb) delete b
Delete all breakpoints? (y or n) y
warning: Error removing breakpoint 1
(gdb) delete b
(gdb) delete b
(gdb) c
Continuing.

Program received signal SIGTRAP, Trace/breakpoint trap.
0xc10a7dce in sys_sync () at fs/sync.c:41
41              do_sync(1);
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
utimes_common (path=0x1, times=0xd8) at fs/utimes.c:55
55              struct inode *inode = path->dentry->d_inode;
(gdb) c
Continuing.

Program received signal SIGSEGV, Segmentation fault.
0x0000000b in ?? ()
==================================================================================================

Has anybody came across with similar problem?

Appreciate your early replies and suggestions.

Thanks.

Santosh.