On 2014-10-10 11:14, Christoffer Dall wrote:

This patch adds the necessary support for all host kernel PGSIZE and
VA_SPACE configuration options for both EL2 and the Stage-2 page 
tables.

However, for 40bit and 42bit PARange systems, the architecture 
mandates
that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2
pagge tables than levels of host kernel page tables.  At the same 
time,
systems with a PARange > 42bit, we limit the IPA range by always 
setting
VTCR_EL2.T0SZ to 24.

To solve the situation with different levels of page tables for 
Stage-2
translation than the host kernel page tables, we allocate a dummy PGD
with pointers to our actual inital level Stage-2 page table, in order
for us to reuse the kernel pgtable manipulation primitives.  
Reproducing
all these in KVM does not look pretty and unnecessarily complicates 
the
32-bit side.

Systems with a PARange < 40bits are not yet supported.

 [ I have reworked this patch from its original form submitted by
   Jungseok to take the architecture constraints into consideration.
   There were too many changes from the original patch for me to
   preserve the authorship.  Thanks to Catalin Marinas for his help 
in
   figuring out a good solution to this challenge.  I have also fixed
   various bugs and missing error code handling from the original
   patch. - Christoffer ]

Cc: Marc Zyngier <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jungseok Lee <redacted>
Signed-off-by: Christoffer Dall <redacted>

Acked-by: Marc Zyngier <redacted>

         M.
-- 
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