On Mon, Apr 30, 2007 at 10:20:53PM -0600, Eric W. Biederman wrote: > Vivek Goyal <vgoyal at in.ibm.com> writes: > > > On Mon, Apr 30, 2007 at 05:17:07PM +0200, Andi Kleen wrote: > >> On Monday 30 April 2007 17:12:39 Eric W. Biederman wrote: > >> > > >> > Currently because vmlinux does not reflect that the kernel is relocatable > >> > we still have to support CONFIG_PHYSICAL_START. So this patch adds a small > >> > c program to do what we cannot do with a linker script set the elf header > >> > type to ET_DYN. > >> > > >> > Since last time I have fixed the type to be in my code ET_DYN (oops), > >> > and verified this works with kexec. I realized while testing that we > >> > don't have anyway of identifying a kernel vmlinux as linux so we > >> > probably want to add an ELF note but that will be another patch. > >> > >> The patch is ok for me, but does it pass Vivek's usual testing? > > > > I am facing one issue with this patch. gdb can not analyze the > > resulting kernel core file. Looks like gdb treats vmlinux differently if > > ELF header type is "ET_DYN". It reads the symbol values incorrectly. > > Weird. > > > For example, symbol value of "panic_timeout" is 0xffffffff808a1fa8 but > > gdb somehow things that it is 0xffffffff008aaebf. Looks like it is > > performing some relocation. > > > > I am using GNU gdb Red Hat Linux (6.5-5.fc6rh). > > Does it take a kernel core file to reproduce this problem? > Or can you just open up gdb on a vmlinux and look at the symbol > address? It takes a core file to reproduce the problem. Without core file gdb can get right symbol addresses. > > At least without a core file it is working on with gdb 6.4. > This seems to be a problem with gdb 6.5. I transferred the dump to a different machine having GNU gdb 6.4, and it works fine there. Thanks Vivek
