From mboxrd@z Thu Jan 1 00:00:00 1970 From: gprabhunath@gmail.com (Prabhu nath) Date: Fri, 20 May 2011 09:53:41 +0530 Subject: [Kgdb-bugreport] KGDB problem at first breakpoint In-Reply-To: References: Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Enabling CONFIG_DEBUG_RODATA also didn't work. -Prabhu On Thu, May 19, 2011 at 6:45 AM, Dongdong Deng wrote: > On Wed, May 18, 2011 at 7:23 PM, Prabhu nath > wrote: > > Dear All, > > > > There is a problem with the KGDB at the very first break point > after > > executing the gdb command "target remote /dev/ttyS0" from the host. > > I have verbatim, followed the KGDB document > > http://kernel.org/pub/linux/kernel/people/jwessel/kdb/ > > > > Problem Logs: > > --------------------- > > > > Details of my hardware and system software: > > ------------------------------------------------------------------- > > > > *Host (Development machine): * > > Intel Pentium IV Machine with Fedora Core 12 > > Linux Version : 2.6.31.5-127.fc12.i686.PAE > > gdb version : GNU gdb (GDB) Fedora (7.0-3.fc12) > > > > *Target:* > > Intel Pentium IV Machine with Fedora Core 12 > > Customized Linux Version : 2.6.38 > > > > Host is connected to Target via a null modem cable > > > > *Snapshot of .config of linux version 2.6.38 on the target * > > * > > * > > # CONFIG_DEBUG_RODATA is not set > > > Hi Prabhu, > > The CONFIG_DEBUG_RODATA was suggested to set at KGDB, > Could you enable it? > > CONFIG_DEBUG_RODATA = y > > Dongdong > > > > > > > CONFIG_HAVE_ARCH_KGDB=y > > CONFIG_FRAME_POINTER=y > > CONFIG_DEBUG_INFO=y > > CONFIG_KGDB=y > > CONFIG_KGDB_SERIAL_CONSOLE=y > > CONFIG_KGDB_LOW_LEVEL_TRAP=y > > > > *Grub config on the target machine* > > * > > * > > title Fedora (2.6.38) > > root (hd0,0) > > kernel /boot/vmlinuz-2.6.38 ro > > root=UUID=fb7800fb-cfe7-438d-bc7f-c153ba4353d1 LANG=en_US.UTF-8 > > SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc > KEYTABLE=us*console=ttyS0,115200n8 > > kgdboc=ttyS0 kgdbwai*t > > initrd /boot/initrd-2.6.38.img > > > > > > On power on of the target, linux kernel boots and the logs are seen on > the > > minicom console of the host and it will wait for the gdb on the host to > > connect. Here is the last 4 lines of the logs seen on the minicom > > > > Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled > > serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A > > 00:06: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A > > kgdb: Registered I/O driver kgdboc. > > kgdb: Waiting for connection from remote gdb.. > > > > *--- Now I close the minicom console (Ctrl-A X) and start the gdb on the > > host. Here is the steps I follow. * > > * > > * > > *On the host machine:* > > * > > * > > > > [root at localhost kgdb]# gdb vmlinux > > > > GNU gdb (GDB) Fedora (7.0-3.fc12) > > Copyright (C) 2009 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-redhat-linux-gnu". > > For bug reporting instructions, please see: > > ... > > Reading symbols from /root/kgdb/vmlinux...done. > > > > (gdb) set remotebaud 115200 > > (gdb) set debug remote 1 > > (gdb) target remote /dev/ttyS0 > > Remote debugging using /dev/ttyS0 > > Sending packet: $qSupported#37...Ack > > Packet received: > > Packet qSupported (supported-packets) is NOT supported > > Sending packet: $Hg0#df...Ack > > Packet received: OK > > Sending packet: $?#3f...Ack > > Packet received: S05 > > Sending packet: $Hc-1#09...Ack > > Packet received: OK > > Sending packet: $qC#b4...Ack > > Packet received: QC01 > > Sending packet: $qAttached#8f...Ack > > Packet received: > > Packet qAttached (query-attached) is NOT supported > > Sending packet: $qOffsets#4b...Ack > > Packet received: > > Sending packet: $g#67...Ack > > Packet received: > > > 36000000ffffffff0abaffff20d98bc06c3f86de783f86de803ac8dd803f86de885747c00202000060000000680000007b00c8dd7b0086deffff0000ffff0000 > > Sending packet: $mc0475788,1#a4...Ack > > Packet received: 0f > > Sending packet: $mc0475788,8#ab...Ack > > Packet received: 0faef889f6ff0d08 > > Sending packet: $mc0475788,7#aa...Ack > > Packet received: 0faef889f6ff0d > > 0xc0475788 in ?? () > > Sending packet: $qSymbol::#5b...Ack > > Packet received: > > Packet qSymbol (symbol-lookup) is NOT supported > > (gdb) s > > Cannot find bounds of current function > > (gdb) > > > > > > *Observation:* > > *1.* Ideally the kernel being debugged should break > at > > legitimate address and the corresponding line number should > > be displayed instead of " 0xc0475788 in ?? ()". > > > > 2. On inspecting section header in vmlinux > executable, > > I found the .text section address range is from > > 0xC1000000 to 0xC1326e58 and no section's > contents > > associate with the address 0xC0475788. > > > > *3.* Hence on single stepping, gdb logs the error > > as* "Cannot > > find bounds of current function"* > > * > > * > > Humbly request you to help me in addressing this issue. > > > > Thanks and Regards, > > Prabhu > > > ------------------------------------------------------------------------------ > > What Every C/C++ and Fortran developer Should Know! > > Read this article and learn how Intel has extended the reach of its > > next-generation tools to help Windows* and Linux* C/C++ and Fortran > > developers boost performance applications - including clusters. > > http://p.sf.net/sfu/intel-dev2devmay > > _______________________________________________ > > Kgdb-bugreport mailing list > > Kgdb-bugreport at lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport > > > -------------- next part -------------- An HTML attachment was scrubbed... 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