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Re: [PATCH] fix alias cache breakage
Hi -
On Mon, Jul 14, 2008 at 01:58:58PM -0500, James Bottomley wrote:
> [...]
> > I understand that, but an implicit heuristic like that will not work
> > in general. What we could do is hardcode a "cache miss in a module?
> > then search vmlinux - if available".
>
> Actually, the most likely case for an unresolved symbol is resolution in
> another module rather than the kernel.
OK, that makes it even worse a candidate for the heuristic. So IMO
the automatic alias cache business should stop at the point where it
searches other CUs in the same module.
> > Remember, we are about to start processing userspace binaries,
> > likely in some shared dwflpp instances. So "global" isn't.
> Then before you begin to do this, you need a namespace
> discriminator. The cache is global to the kernel namespace, so it
> has to tie in to the kernel and its modules. [...]
User namespaces wouldn't be so straightforward; neither shared
libraries or executables would be a proper key for namespaces that are
intended to be complete.
Once we need to leave the confines of a single module to resolve type
names, the script will need to give help in naming types & contexts.
At that point, we might as well implement general casting. See
http://sources.redhat.com/bugzilla/show_bug.cgi?id=6704#c1 for a
possible syntax to implement as part of bug #5634.
- FChE