Re: [PATCH v2] x86: PAT: Documentation: rewrite "MTRR effects on PAT / non-PAT systems"

From: Ingo Molnar
Date: Sat Mar 05 2016 - 06:53:23 EST



* Luis R. Rodriguez <mcgrof@xxxxxxxxxx> wrote:

> The current documentation refers to using set_memory_wc() as a
> possible hole strategy when you have overlapping ioremap() regions,

The whole explanation should talk about virtual aliases over the same physical
address, not some 'overlapping regions'.

I see where this talk about 'overlap' comes: the memtype rbtree in
arch/x86/mm/pat_rbtree.c indeed has memtype ranges that may overlap on the
physical side. But it is highly confusing to call this 'overlapping' on the driver
API documentation level without making it really clear what it's about.

Thanks,

Ingo