From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Date: Fri, 1 Sep 2017 09:06:03 +0000 (+0200)
Subject: mm: don't poison a page if scrub_debug is off
X-Git-Tag: archive/raspbian/4.11.1-1+rpi1~1^2~66^2~1505
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=f65bf735f17235c5077c83550259cacf4090b28b;p=xen.git

mm: don't poison a page if scrub_debug is off

If scrub_debug is off we don't check pages in check_one_page().
Thus there is no reason to ever poison them.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
---

diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index 2c7675b4d5..2b8bb95369 100644
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -714,6 +714,9 @@ static void poison_one_page(struct page_info *pg)
     mfn_t mfn = _mfn(page_to_mfn(pg));
     uint64_t *ptr;
 
+    if ( !scrub_debug )
+        return;
+
     ptr = map_domain_page(mfn);
     *ptr = ~SCRUB_PATTERN;
     unmap_domain_page(ptr);