Hi,
On Mon, 2016-06-20 at 16:36 +0100, James Morse wrote:
> +> > > switch (flag) {
> > +> > > > > > case IND_INDIRECTION:
> > +> > > > > > > > /* Set entry point just before the new list page. */
> > +> > > > > > > > entry = (kimage_entry_t *)addr - 1;
>
> Ah, after this restructuring we end up cleaning this page as we fall-through,
> and one kimage_entry_t at a time as we walk the list.
>
> > > > break;
> ?
I added this in, but that missing break shouldn't cause any problems.
> > +> > > > > > case IND_SOURCE:
> > +> > > > > > > > __flush_dcache_area(addr, PAGE_SIZE);
> > +> > > > > > > > break;
> > +> > > > > > case IND_DESTINATION:
> > +> > > > > > > > break;
> > +> > > > > > default:
> > +> > > > > > > > BUG();
> > +> > > > > > }
> > +> > > > }
> > +}
>
>
> > diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S
> > new file mode 100644
> > index 0000000..51b73cd
> > --- /dev/null
> > +++ b/arch/arm64/kernel/relocate_kernel.S
>
> [ ... ]
>
> > +.ltorg
> > +
> > +.align 3> > > > /* To keep the 64-bit values below naturally aligned. */
> > +
> > +.Lcopy_end:
> > +.org> > > > KEXEC_CONTROL_PAGE_SIZE
>
>
> On 16/06/16 23:41, Geoff Levand wrote:
> > This is to check if arm64_relocate_new_kernel gets too
> > big. The assembler should give an error if the location
> > counter is set backwards.
>
> Cunning. (probably worth a comment).
I thought this was the standard way to do it...
> This looks like it is need because we hard-coded KEXEC_CONTROL_PAGE_SIZE in
> kexec.h, so the code must be smaller than that size.
> It looks like this value is only ever passed to get_order(), could we just pass
> the actual size? It shouldn't matter if it grows >4K, as the core code will
> allocate enough memory, and the memcpy() in machine_kexec() uses the size too.
I thought 4K would be enough, but if some debugging code is
added it could get too big.
> Reviewed-by: James Morse <james.morse at arm.com>
Thanks for your comments.
-Geoff
