Kernel 4.7: PAGE_GUARDED and _PAGE_NO_CACHE

[Aneesh Kumar K.V]

Darren Stevens <darren at stevens-zone.net> writes:

> Hello Christian

> That's not where I ended up with my bisect, this commit is about 10 before the
> one I found to be bad, which is:
>
> commit d6a9996e84ac4beb7713e9485f4563e100a9b03e
> Author: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
> Date:   Fri Apr 29 23:26:21 2016 +1000
>
>     powerpc/mm: vmalloc abstraction in preparation for radix
>     
>     The vmalloc range differs between hash and radix config. Hence make
>     VMALLOC_START and related constants a variable which will be runtime
>     initialized depending on whether hash or radix mode is active.
>     
>     Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
>     [mpe: Fix missing init of ioremap_bot in pgtable_64.c for ppc64e]
>     Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
>

Can you check the value of ISA_IO_BASE where you are
using it. If you are calling it early, you will find wrong value in
that. With the latest kernel it is a variable and is initialized in
hash__early_init_mmu();

-aneesh