Hi, Jason Wessel <[EMAIL PROTECTED]> writes:
> I have not looked at the fedora kernels, but it would appear that if > there was a shift that some part of the loader or some kernel patch has > done a runtime relocation. Well, it appears to be the case, but I've only tested that one symbol. I could go randomly sample some other symbols, too, if that would help. It certainly seems weird to me, but it does seem consistent. :( > If you knew for absolutely certain that everything was relocated with an > offset, then you could simply load the symbols with an offset too. You Um, okay..... How do I do that? My GDB Fu is weak here; how do I tell gdb that the symbols in vmlinux are all offset? Or how do I manipulate the vmlinux binary to offset the symbols? > are not going to be able to "easily" debug kernel modules of course > without patching gdb to have the kernel module support. What patch do I need to support this? I thought that I just needed to add-symbol-file <module> <offset>, right? Why wouldn't that work? Thanks for the feedback! > Jason. -derek > Derek Atkins wrote: >> Hi everyone, >> >> I'm using Fedora 7; I've backported the 2.6.23-rc8-mm1 broken-out kgdb >> patches (git-kgdb.patch, git-kgdb-fixup.patch, >> kgdb-fix-docbook-and-kernel-doc-typos.patch, and >> kgdb-fix-help-text.patch) to the Fedora 2.6.22.5-76 kernel >> and I can connect just fine from my host system to the >> target running in vmware. >> >> Unfortunately, gdb shows no symbols: >> >> [EMAIL PROTECTED] ~]$ gdb /vmlinux.kgdb >> GNU gdb Red Hat Linux (6.6-15.fc7rh) >> Copyright (C) 2006 Free Software Foundation, Inc. >> GDB is free software, covered by the GNU General Public License, and you are >> welcome to change it and/or distribute copies of it under certain conditions. >> Type "show copying" to see the conditions. >> There is absolutely no warranty for GDB. Type "show warranty" for details. >> This GDB was configured as "i386-redhat-linux-gnu"... >> Using host libthread_db library "/lib/libthread_db.so.1". >> (gdb) target remote /dev/pts/18 >> Remote debugging using /dev/pts/18 >> warning: shared library handler failed to enable breakpoint >> 0xc04579aa in ?? () >> (gdb) bt >> #0 0xc04579aa in ?? () >> #1 0xc07a2fc8 in ?? () >> #2 0xc055fe3e in ?? () >> #3 0xc07a2fe0 in ?? () >> #4 0xc04597f6 in ?? () >> #5 0x00000004 in ?? () >> #6 0xc072a000 in ?? () >> #7 0x00000004 in ?? () >> #8 0xdfb247e0 in ?? () >> #9 0xc07a2ff8 in ?? () >> #10 0xc045ab73 in ?? () >> #11 0xc072a02c in ?? () >> #12 0xc0736f54 in ?? () >> #13 0x00000004 in ?? () >> #14 0xc045aaad in ?? () >> #15 0xc0736f70 in ?? () >> #16 0xc0407309 in ?? () >> #17 0x00000000 in ?? () >> (gdb) p sys_close >> $1 = {long int (unsigned int)} 0xc107e341 <sys_close> >> (gdb) >> >> This matches what's in the System.map file: >> >> [EMAIL PROTECTED] ~] grep sys_close .../System.map >> c107e341 T sys_close >> c12deb58 r __ksymtab_sys_close >> c12e4918 r __kcrctab_sys_close >> c12ea703 r __kstrtab_sys_close >> >> However, the system running this kernel shows a different value: >> >> [EMAIL PROTECTED] #] grep sys_close /proc/kallsyms >> c047e341 T sys_close >> c06deb58 r __ksymtab_sys_close >> c06e4918 r __kcrctab_sys_close >> c06ea703 r __kstrtab_sys_close >> >> I find it interesting that the symbols are EXACTLY 0x600000 different, >> but I haven't been able to track down this difference. Am I doing >> something wrong? Is there some particular kernel configuration I need >> to set for my kernel? Why are the symbols in the running kernel at >> different addresses than the underlying vmlinux? >> >> (I'll also note that I see a similar skew on my non-rebuilt Fedora >> kernel, comparing System.map to /proc/kallsyms, so it's probably not >> specifically a kgdb issue, it could be a Fedora issue.. but I'd still >> like help in working around this disparity). >> >> Thanks in advance for any help. >> >> -derek >> >> > > > -- Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory Member, MIT Student Information Processing Board (SIPB) URL: http://web.mit.edu/warlord/ PP-ASEL-IA N1NWH [EMAIL PROTECTED] PGP key available ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Kgdb-bugreport mailing list Kgdb-bugreport@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kgdb-bugreport