[PATCH 01/15] ARM: add mem_type prot_pte accessor

Russell King - ARM Linux linux at arm.linux.org.uk
Tue Sep 18 17:04:42 EDT 2012


On Sat, Sep 15, 2012 at 11:34:36AM -0400, Christoffer Dall wrote:
> From: Marc Zyngier <marc.zyngier at arm.com>
> 
> The KVM hypervisor mmu code requires access to the mem_type prot_pte
> field when setting up page tables pointing to a device. Unfortunately,
> the mem_type structure is opaque.
> 
> Add an accessor (get_mem_type_prot_pte()) to retrieve the prot_pte
> value.
> 
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> Signed-off-by: Christoffer Dall <c.dall at virtualopensystems.com>

Is there a reason why we need this to be exposed, along with all the
page table manipulation in patch 7?

Is there a reason why we can't have new MT_ types for PAGE_HYP and
the HYP MT_DEVICE type (which is the same as MT_DEVICE but with
PTE_USER set) and have the standard ARM/generic kernel code build
those mappings?

That would (it seems) also avoid the need to export the pXd_clear_bad()
acessors too...



More information about the linux-arm-kernel mailing list