Re: [PATCH 1/2 v6] kdump: add the vmcoreinfo documentation

Dave Anderson
2019-01-14T20:26:40Z

----- Original Message -----
> On Mon, Jan 14, 2019 at 03:07:33PM -0500, Dave Anderson wrote:
> > That's what it *does* utilize -- it takes a standalone vmcore dumpfile, and
> > pulls out the OSRELEASE string from it, so that a user can determine what
> > vmlinux file should be used with that vmcore for normal crash analysis.
>
> And the vmcoreinfo is part of the vmcore, right?

Correct.

>
> So it can just as well read out the address of init_uts_ns and get the
> kernel version from there.

No. It needs *both* the vmlinux file and the vmcore file in order to read kernel
virtual memory, so just having a kernel virtual address is insufficient.

So it's a chicken-and-egg situation. This particular --osrelease option is used
to determine *what* vmlinux file would be required for an actual crash analysis
session.

Dave