From: Peng Fan <van.freenix@gmail.com>
Date: Thu, 12 May 2016 13:03:08 +0000 (+0800)
Subject: xen/arm: mm: fix nr_second calculation in setup_frametable_mappings
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~1115
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=2c86f0e1ac35b4c9e9502d969693f3264d3eda1e;p=xen.git

xen/arm: mm: fix nr_second calculation in setup_frametable_mappings

On ARM64, "frametable_size >> SECOND_SHIFT" computes the number
of second level entries, not the number of second level pages.

"ROUNDUP(frametable_size, FIRST_SIZE) >> FIRST_SHIFT" which computes
the number of the first level entries (the number of second level pages),
is the correct one that should be used.

Signed-off-by: Peng Fan <van.freenix@gmail.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
---

diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c
index 94ea0541cd..b46e23ed8c 100644
--- a/xen/arch/arm/mm.c
+++ b/xen/arch/arm/mm.c
@@ -770,7 +770,8 @@ void __init setup_frametable_mappings(paddr_t ps, paddr_t pe)
     base_mfn = alloc_boot_pages(frametable_size >> PAGE_SHIFT, 32<<(20-12));
 
 #ifdef CONFIG_ARM_64
-    nr_second = frametable_size >> SECOND_SHIFT;
+    /* Compute the number of second level pages. */
+    nr_second = ROUNDUP(frametable_size, FIRST_SIZE) >> FIRST_SHIFT;
     second_base = alloc_boot_pages(nr_second, 1);
     second = mfn_to_virt(second_base);
     for ( i = 0; i < nr_second; i++ )