Re: [PATCH v2 1/2] x86: Check return values from early_memremap calls

[Borislav Petkov <bp@xxxxxxxxx>]

On Thu, Nov 10, 2022 at 08:07:53AM -0800, Dave Hansen wrote:
> On 11/10/22 07:45, Ross Philipson wrote:
> >     dt = early_memremap(initial_dtb, map_len);
> > +   if (!dt) {
> > +           pr_warn("failed to memremap initial dtb\n");
> > +           return;
> > +   }
> 
> Are all of these new pr_warn/err()'s really adding much value?  They all
> look pretty generic.  It makes me wonder if we should just spit out a
> generic message in early_memremap() and save all the callers the trouble.

Well, let's see.

early_memremap() calls __early_ioremap() and that one already warns befofe each
NULL return. So I guess we don't need the error messages as we will know where
it starts failing.

I guess we still need the error handling though.

I.e., this above should be:

    dt = early_memremap(initial_dtb, map_len);
+   if (!dt)
+           return;

so that we don't go off into the weeds with a NULL ptr.

Or?

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette