xen/mm: zero PTEs for non-present MFNs in the initial page table
authorDavid Vrabel <david.vrabel@citrix.com>
Mon, 9 Jul 2012 10:39:06 +0000 (11:39 +0100)
committerKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Thu, 19 Jul 2012 19:51:44 +0000 (15:51 -0400)
commit66a27dde9ae96e35278983f2e59bea04eb714cd0
tree17e7b1054153131a11ef9f437787424be5b901f1
parentd095d43e78dd811d5c02c25e207c3364019b5a77
xen/mm: zero PTEs for non-present MFNs in the initial page table

When constructing the initial page tables, if the MFN for a usable PFN
is missing in the p2m then that frame is initially ballooned out.  In
this case, zero the PTE (as in decrease_reservation() in
drivers/xen/balloon.c).

This is obviously safe instead of having an valid PTE with an MFN of
INVALID_P2M_ENTRY (~0).

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
arch/x86/xen/mmu.c