From mboxrd@z Thu Jan 1 00:00:00 1970 From: gprabhunath@gmail.com (Prabhu nath) Date: Tue, 31 May 2011 14:21:27 +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 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. Thanks, Prabhu On Fri, May 27, 2011 at 10:06 PM, Dongdong Deng wrote: > On Fri, May 20, 2011 at 12:23 PM, Prabhu nath > wrote: > > Enabling CONFIG_DEBUG_RODATA also didn't work. > > > I am sorry, the CONFIG_DEBUG_RODATA should be disabled... > > > Could you try to pass full parameters to kgdboc module? > "kgdboc=ttyS0,115200 kgdbwait" > > > Dongdong > > > > > > > -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 > >> > >> >> > >> > 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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