No luck. Atleast, I am interested to know, if it is working for anyone or there is a bug in kgdb implementation in the kernel. If so, I can cool off for some more days until it gets rectified. <br><br>Thanks,<br>Prabhu<br>
<br><br><div class="gmail_quote">On Fri, May 27, 2011 at 10:06 PM, Dongdong Deng <span dir="ltr"><<a href="mailto:libfetion@gmail.com">libfetion@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">On Fri, May 20, 2011 at 12:23 PM, Prabhu nath <<a href="mailto:gprabhunath@gmail.com">gprabhunath@gmail.com</a>> wrote:<br>
> Enabling CONFIG_DEBUG_RODATA also didn't work.<br>
<br>
<br>
</div>I am sorry, the CONFIG_DEBUG_RODATA should be disabled...<br>
<br>
<br>
Could you try to pass full parameters to kgdboc module?<br>
"kgdboc=ttyS0,115200 kgdbwait"<br>
<font color="#888888"><br>
<br>
Dongdong<br>
</font><div><div></div><div class="h5"><br>
<br>
<br>
><br>
> -Prabhu<br>
><br>
><br>
> On Thu, May 19, 2011 at 6:45 AM, Dongdong Deng <<a href="mailto:libfetion@gmail.com">libfetion@gmail.com</a>> wrote:<br>
>><br>
>> On Wed, May 18, 2011 at 7:23 PM, Prabhu nath <<a href="mailto:gprabhunath@gmail.com">gprabhunath@gmail.com</a>><br>
>> wrote:<br>
>> > Dear All,<br>
>> ><br>
>> > There is a problem with the KGDB at the very first break point<br>
>> > after<br>
>> > executing the gdb command "target remote /dev/ttyS0" from the host.<br>
>> > I have verbatim, followed the KGDB document<br>
>> > <a href="http://kernel.org/pub/linux/kernel/people/jwessel/kdb/" target="_blank">http://kernel.org/pub/linux/kernel/people/jwessel/kdb/</a><br>
>> ><br>
>> > Problem Logs:<br>
>> > ---------------------<br>
>> ><br>
>> > Details of my hardware and system software:<br>
>> > -------------------------------------------------------------------<br>
>> ><br>
>> > *Host (Development machine): *<br>
>> > Intel Pentium IV Machine with Fedora Core 12<br>
>> > Linux Version : 2.6.31.5-127.fc12.i686.PAE<br>
>> > gdb version : GNU gdb (GDB) Fedora (7.0-3.fc12)<br>
>> ><br>
>> > *Target:*<br>
>> > Intel Pentium IV Machine with Fedora Core 12<br>
>> > Customized Linux Version : 2.6.38<br>
>> ><br>
>> > Host is connected to Target via a null modem cable<br>
>> ><br>
>> > *Snapshot of .config of linux version 2.6.38 on the target *<br>
>> > *<br>
>> > *<br>
>> > # CONFIG_DEBUG_RODATA is not set<br>
>><br>
>><br>
>> Hi Prabhu,<br>
>><br>
>> The CONFIG_DEBUG_RODATA was suggested to set at KGDB,<br>
>> Could you enable it?<br>
>><br>
>> CONFIG_DEBUG_RODATA = y<br>
>><br>
>> Dongdong<br>
>><br>
><br>
>><br>
>> ><br>
>> > CONFIG_HAVE_ARCH_KGDB=y<br>
>> > CONFIG_FRAME_POINTER=y<br>
>> > CONFIG_DEBUG_INFO=y<br>
>> > CONFIG_KGDB=y<br>
>> > CONFIG_KGDB_SERIAL_CONSOLE=y<br>
>> > CONFIG_KGDB_LOW_LEVEL_TRAP=y<br>
>> ><br>
>> > *Grub config on the target machine*<br>
>> > *<br>
>> > *<br>
>> > title Fedora (2.6.38)<br>
>> > root (hd0,0)<br>
>> > kernel /boot/vmlinuz-2.6.38 ro<br>
>> > root=UUID=fb7800fb-cfe7-438d-bc7f-c153ba4353d1 LANG=en_US.UTF-8<br>
>> > SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc<br>
>> > KEYTABLE=us*console=ttyS0,115200n8<br>
>> > kgdboc=ttyS0 kgdbwai*t<br>
>> > initrd /boot/initrd-2.6.38.img<br>
>> ><br>
>> ><br>
>> > On power on of the target, linux kernel boots and the logs are seen on<br>
>> > the<br>
>> > minicom console of the host and it will wait for the gdb on the host to<br>
>> > connect. Here is the last 4 lines of the logs seen on the minicom<br>
>> ><br>
>> > Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled<br>
>> > serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A<br>
>> > 00:06: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A<br>
>> > kgdb: Registered I/O driver kgdboc.<br>
>> > kgdb: Waiting for connection from remote gdb..<br>
>> ><br>
>> > *--- Now I close the minicom console (Ctrl-A X) and start the gdb on the<br>
>> > host. Here is the steps I follow. *<br>
>> > *<br>
>> > *<br>
>> > *On the host machine:*<br>
>> > *<br>
>> > *<br>
>> ><br>
>> > [root@localhost kgdb]# gdb vmlinux<br>
>> ><br>
>> > GNU gdb (GDB) Fedora (7.0-3.fc12)<br>
>> > Copyright (C) 2009 Free Software Foundation, Inc.<br>
>> > License GPLv3+: GNU GPL version 3 or later<br>
>> > <<a href="http://gnu.org/licenses/gpl.html" target="_blank">http://gnu.org/licenses/gpl.html</a><br>
>> >><br>
>> > This is free software: you are free to change and redistribute it.<br>
>> > There is NO WARRANTY, to the extent permitted by law. Type "show<br>
>> > copying"<br>
>> > and "show warranty" for details.<br>
>> > This GDB was configured as "i686-redhat-linux-gnu".<br>
>> > For bug reporting instructions, please see:<br>
>> > <<a href="http://www.gnu.org/software/gdb/bugs/" target="_blank">http://www.gnu.org/software/gdb/bugs/</a>>...<br>
>> > Reading symbols from /root/kgdb/vmlinux...done.<br>
>> ><br>
>> > (gdb) set remotebaud 115200<br>
>> > (gdb) set debug remote 1<br>
>> > (gdb) target remote /dev/ttyS0<br>
>> > Remote debugging using /dev/ttyS0<br>
>> > Sending packet: $qSupported#37...Ack<br>
>> > Packet received:<br>
>> > Packet qSupported (supported-packets) is NOT supported<br>
>> > Sending packet: $Hg0#df...Ack<br>
>> > Packet received: OK<br>
>> > Sending packet: $?#3f...Ack<br>
>> > Packet received: S05<br>
>> > Sending packet: $Hc-1#09...Ack<br>
>> > Packet received: OK<br>
>> > Sending packet: $qC#b4...Ack<br>
>> > Packet received: QC01<br>
>> > Sending packet: $qAttached#8f...Ack<br>
>> > Packet received:<br>
>> > Packet qAttached (query-attached) is NOT supported<br>
>> > Sending packet: $qOffsets#4b...Ack<br>
>> > Packet received:<br>
>> > Sending packet: $g#67...Ack<br>
>> > Packet received:<br>
>> ><br>
>> > 36000000ffffffff0abaffff20d98bc06c3f86de783f86de803ac8dd803f86de885747c00202000060000000680000007b00c8dd7b0086deffff0000ffff0000<br>
>> > Sending packet: $mc0475788,1#a4...Ack<br>
>> > Packet received: 0f<br>
>> > Sending packet: $mc0475788,8#ab...Ack<br>
>> > Packet received: 0faef889f6ff0d08<br>
>> > Sending packet: $mc0475788,7#aa...Ack<br>
>> > Packet received: 0faef889f6ff0d<br>
>> > 0xc0475788 in ?? ()<br>
>> > Sending packet: $qSymbol::#5b...Ack<br>
>> > Packet received:<br>
>> > Packet qSymbol (symbol-lookup) is NOT supported<br>
>> > (gdb) s<br>
>> > Cannot find bounds of current function<br>
>> > (gdb)<br>
>> ><br>
>> ><br>
>> > *Observation:*<br>
>> > *1.* Ideally the kernel being debugged should break<br>
>> > at<br>
>> > legitimate address and the corresponding line number should<br>
>> > be displayed instead of " 0xc0475788 in ?? ()".<br>
>> ><br>
>> > 2. On inspecting section header in vmlinux<br>
>> > executable,<br>
>> > I found the .text section address range is from<br>
>> > 0xC1000000 to 0xC1326e58 and no section's<br>
>> > contents<br>
>> > associate with the address 0xC0475788.<br>
>> ><br>
>> > *3.* Hence on single stepping, gdb logs the error<br>
>> > as* "Cannot<br>
>> > find bounds of current function"*<br>
>> > *<br>
>> > *<br>
>> > Humbly request you to help me in addressing this issue.<br>
>> ><br>
>> > Thanks and Regards,<br>
>> > Prabhu<br>
>> ><br>
>> > ------------------------------------------------------------------------------<br>
>> > What Every C/C++ and Fortran developer Should Know!<br>
>> > Read this article and learn how Intel has extended the reach of its<br>
>> > next-generation tools to help Windows* and Linux* C/C++ and Fortran<br>
>> > developers boost performance applications - including clusters.<br>
>> > <a href="http://p.sf.net/sfu/intel-dev2devmay" target="_blank">http://p.sf.net/sfu/intel-dev2devmay</a><br>
>> > _______________________________________________<br>
>> > Kgdb-bugreport mailing list<br>
>> > <a href="mailto:Kgdb-bugreport@lists.sourceforge.net">Kgdb-bugreport@lists.sourceforge.net</a><br>
>> > <a href="https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport" target="_blank">https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport</a><br>
>> ><br>
><br>
><br>
</div></div></blockquote></div><br>