[PATCH for 4.5] xen/arm: p2m: Correctly initialize cur_offset

[Julien Grall <julien.grall@linaro.org>]

{~0,} only initializes the first cell of the array to ~0. The other cells
are initialized to 0.

Change the initialization to a loop and, at the same time, do the same
for the mappings.

This is fixing boot after 82985d7 "xen: arm: handle variable p2m levels
in apply_p2m_changes" on platform where the root-level doesn't have
concatenate table (such as the Foundation Model).

---
    This is a bug fix for Xen 4.5. This make Xen booting again on the
    Foundation Model and any platform that doesn't have concatenate
    table for root-level.
---
 xen/arch/arm/p2m.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index 70929fc..3fa7e63 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -716,15 +716,21 @@ static int apply_p2m_changes(struct domain *d,
 {
     int rc, ret;
     struct p2m_domain *p2m = &d->arch.p2m;
-    lpae_t *mappings[4] = { NULL, };
+    lpae_t *mappings[4];
     paddr_t addr, orig_maddr = maddr;
     unsigned int level = 0;
     unsigned int cur_root_table = ~0;
-    unsigned int cur_offset[4] = { ~0, };
+    unsigned int cur_offset[4];
     unsigned int count = 0;
     bool_t flush = false;
     bool_t flush_pt;
 
+    for (level = 0; level < 4; level++)
+    {
+        mappings[level] = NULL;
+        cur_offset[level] = ~0;
+    }
+
     /* Some IOMMU don't support coherent PT walk. When the p2m is
      * shared with the CPU, Xen has to make sure that the PT changes have
      * reached the memory
-- 
1.7.10.4