Hiro Sugawara wrote:
>
> Sorry, I am not yet clear. My understanding is:
>
> 1) System.map is created from vmlinux at kernel build time and placed
> in /boot
> 2) /sbin/vmdump simply copies /boot/System.map to /var/vmdump at a
> system boot time (i.e. _after_ a kernel panic, not when a panic
> occurs)
>
> So, I guess, as long as you do not rebuild vmlinux after you get a
> vmdump, System.map can always be reproduced from the vmlinux you used
> for the panicking system.
That is correct. Most people don't panic()/die_if_kernel(), and
then reboot on a new kernel. Most == nearly all. People who boot
on different kernels either changed their lilo.conf before the
crash but didn't boot on the new kernel (after running 'lilo'), or
decided to boot on a different kernel by choice.
Again, that doesn't happen often. People almost always come up on
the kernel they were previously running. They don't change the
kernel until they need to or want to try a fix.
--Matt
> ????
>
> hiro
>
> > -----Original Message-----
> > From: Tachino Nobuhiro [mailto:tachino@xxxxxxxxxxxxxxxxxxxxx]
> > Sent: Wednesday, July 18, 2001 19:19
> > To: Hiro Sugawara
> > Cc: 'Matt D. Robinson'; lkcd@xxxxxxxxxxx
> > Subject: Re: Module support
> >
> >
> >
> > At Wed, 18 Jul 2001 14:49:23 -0700,
> > Hiro Sugawara wrote:
> > >
> > > What about my original question about the necessity of System.map?
> > > I found the kernel Makefile actually uses nm to create it. So, as
> > > long as the kernel image is available, it doesn't seem necessary.
> > >
> >
> > If you use lcrash with a live system, vmlinux is okay. But
> > if you examine a saved crash dump, you need the System.map of
> > the kernel
> > which is running when panic occurred. You can retrieve symbol
> > information from vmlinux, but current vmdump command saves
> > only System.map.
> >
> > Am I missing something too :-)
> >
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