From: Roger Pau Monne <roger.pau@citrix.com>
Date: Thu, 11 Jan 2018 11:41:20 +0000 (+0000)
Subject: xen/pvshim: set max_pages to the value of tot_pages
X-Git-Tag: archive/raspbian/4.11.1-1+rpi1~1^2~66^2~776
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=b667d9f62f17aa94c247a7774a09a624813e2e7e;p=xen.git

xen/pvshim: set max_pages to the value of tot_pages

So that the guest is not able to deplete the memory pool of the shim
itself by trying to balloon up.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---

diff --git a/xen/arch/x86/pv/shim.c b/xen/arch/x86/pv/shim.c
index 6dc1ee45d7..e3e101a5b1 100644
--- a/xen/arch/x86/pv/shim.c
+++ b/xen/arch/x86/pv/shim.c
@@ -204,6 +204,12 @@ void __init pv_shim_setup_dom(struct domain *d, l4_pgentry_t *l4start,
                                (hypercall_fn_t *)pv_shim_grant_table_op,
                                (hypercall_fn_t *)pv_shim_grant_table_op);
     guest = d;
+
+    /*
+     * Set the max pages to the current number of pages to prevent the
+     * guest from depleting the shim memory pool.
+     */
+    d->max_pages = d->tot_pages;
 }
 
 static void write_start_info(struct domain *d)