Re: [PATCH 11/19] mmu: introduce pbl_remap_range()

[Sascha Hauer <s.hauer@pengutronix.de>]

On Tue, Jan 06, 2026 at 09:50:04AM +0100, Ahmad Fatoum wrote:
> On 1/5/26 13:15, Ahmad Fatoum wrote:
> > On 1/5/26 12:26 PM, Sascha Hauer wrote:
> >> Add PBL-specific memory remapping function that always uses page-wise
> >> mapping (ARCH_MAP_FLAG_PAGEWISE) for fine-grained permissions on
> >> adjacent ELF segments with different protection requirements.
> >>
> >> Wraps arch-specific __arch_remap_range() for ARMv7 (4KB pages) and
> >> ARMv8 (page tables with BBM). Needed for ELF segment permission setup.
> >>
> >> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> > 
> > Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> 
> 
> Hmm, a question: Why do we need to preemptively break up pages?
> Doesn't normal remapping do that already? My understanding was
> that we only did it here to allow remapping while executing from
> it, but in the PBL ELF loader we are not executing from there,
> so there should not be an issue.

Yes, I think the ARCH_MAP_FLAG_PAGEWISE flag can be dropped here.
In the end it seems we do not the flag anymore when loading the
ELF image in PBL.

Sascha

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