Re: [PATCH] x86/dmi: Switch dmi_remap to ioremap_cache

From: Andy Lutomirski
Date: Thu Mar 09 2017 - 13:14:29 EST


On Thu, Mar 9, 2017 at 9:51 AM, Arjan van de Ven <arjan@xxxxxxxxxxxxxxx> wrote:
> On 3/9/2017 9:48 AM, Julian Brost wrote:
>
>> I'm note entirely sure whether it's actually the kernel or HP to blame,
>> but for now, hp-health is completely broken on 4.9 (probably on
>> everything starting from 4.6), so this patch should be reviewed again.
>
>
> it looks like another kernel driver is doing a conflicting mapping.
> do these HP tools come with their own kernel drivers or are those in the
> upstream kernel nowadays?
>

I assume that the kernel DMI driver itself is now a conflicting
mapping. I wonder if it could register some kind of resource so that
/dev/mem knows to just map it writeback.

On the other hand, the right answer is to use /sys/firmware/dmi. I'm
not sure the kernel ABI stability guarantee applies to /dev/mem.

--Andy