From: Keir Fraser <keir@xen.org>
Date: Tue, 18 Jan 2011 09:04:04 +0000 (+0000)
Subject: xen: fix XEN_DOMCTL_memory_mapping to not return with domain RCU lock held
X-Git-Tag: 4.1.0-rc2~22
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=9fd6c06946e2d3782199547771f54d562cd0f85a;p=xen.git

xen: fix XEN_DOMCTL_memory_mapping to not return with domain RCU lock held

Broken in 20358:ecc649ec3675

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---

diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index 6652aad8af..6fb5504d78 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -965,15 +965,15 @@ long arch_do_domctl(
         if ( (mfn + nr_mfns - 1) < mfn ) /* wrap? */
             break;
 
-        ret = -ESRCH;
-        if ( unlikely((d = rcu_lock_domain_by_id(domctl->domain)) == NULL) )
-            break;
-
         ret = -EPERM;
         if ( !IS_PRIV(current->domain) &&
              !iomem_access_permitted(current->domain, mfn, mfn + nr_mfns - 1) )
             break;
 
+        ret = -ESRCH;
+        if ( unlikely((d = rcu_lock_domain_by_id(domctl->domain)) == NULL) )
+            break;
+
         ret=0;
         if ( domctl->u.memory_mapping.add_mapping )
         {