From: Ian Campbell <ian.campbell@citrix.com>
Date: Thu, 10 Oct 2013 14:43:44 +0000 (+0100)
Subject: xen: arm: correctly round down MFN to 1GB boundary make sure pagetable mask macros... 
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~6129
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https://%22%22/%22http:/www.example.com/cgi/%22https:/%22%22?a=commitdiff_plain;h=80a7e7eaa177af948b1f4cc954bf2d39ee182724;p=xen.git

xen: arm: correctly round down MFN to 1GB boundary make sure pagetable mask macros as physaddr size

~FIRST_MASK is nothing like correct for rounding down an MFN. It is the
inverse *and* an address not a framenumber so wrong in every dimension! We
cannot use FIRST_MASK since that would mask off any zeroeth level bits.
Instead calculate the correct value from FIRST_SIZE.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Julien Grall <julien.grall@linaro.org>
---

diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 1773ffe3b5..123280e826 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -639,7 +639,7 @@ void __init setup_xenheap_mappings(unsigned long base_mfn,
     end_mfn = base_mfn + nr_mfns;
 
     /* Align to previous 1GB boundary */
-    base_mfn &= ~FIRST_MASK;
+    base_mfn &= ~((FIRST_SIZE>>PAGE_SHIFT)-1);
 
     offset = base_mfn - xenheap_mfn_start;
     vaddr = DIRECTMAP_VIRT_START + offset*PAGE_SIZE;