From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Date: Mon, 29 Apr 2013 17:04:26 +0000 (+0100)
Subject: xen/arm: move the tlb_flush in create_p2m_entries to the end of the function
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~6943
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=11d8866da50a75ef5089faebdfa37164bdcb7545;p=xen.git

xen/arm: move the tlb_flush in create_p2m_entries to the end of the function

Move the flush after the pagetable entry has actually been written to
avoid races with other vcpus refreshing the same entriy.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
---

diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index 1e8c8b4027..9fc55346d7 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -133,7 +133,7 @@ static int create_p2m_entries(struct domain *d,
                      paddr_t maddr,
                      int mattr)
 {
-    int rc;
+    int rc, flush;
     struct p2m_domain *p2m = &d->arch.p2m;
     lpae_t *first = NULL, *second = NULL, *third = NULL;
     paddr_t addr;
@@ -186,10 +186,8 @@ static int create_p2m_entries(struct domain *d,
             third = map_domain_page(second[second_table_offset(addr)].p2m.base);
             cur_second_offset = second_table_offset(addr);
         }
-        /* else: third already valid */
 
-        if ( third[third_table_offset(addr)].p2m.valid )
-            flush_tlb_all_local();
+        flush = third[third_table_offset(addr)].p2m.valid;
 
         /* Allocate a new RAM page and attach */
         switch (op) {
@@ -226,6 +224,9 @@ static int create_p2m_entries(struct domain *d,
                 }
                 break;
         }
+
+        if ( flush )
+            flush_tlb_all_local();
     }
 
     rc = 0;