[Xen-devel] [PATCH] xen/pvh: trap access to IO port range 0xcf8-0xcfb

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

This is needed so Xen can properly trap 4 byte accesses to 0xcf8 in order to
keep consistency with accesses to 0xcfc.

Signed-off-by: Roger Pau Monnà <roger.pau@xxxxxxxxxx>
Cc: Jan Beulich <jbeulich@xxxxxxxx>
Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 xen/arch/x86/setup.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 3b9aee5..c6e50cb 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1527,7 +1527,7 @@ static int __hwdom_init io_bitmap_cb(unsigned long s, 
unsigned long e,
 
 void __hwdom_init setup_io_bitmap(struct domain *d)
 {
-    int rc;
+    int rc, i;
 
     ASSERT(is_hardware_domain(d));
     if ( has_hvm_container_domain(d) )
@@ -1535,6 +1535,12 @@ void __hwdom_init setup_io_bitmap(struct domain *d)
         rc = rangeset_report_ranges(d->arch.ioport_caps, 0, 0x10000,
                                     io_bitmap_cb, d);
         BUG_ON(rc);
+        /*
+         * NB: we need to trap accesses to the range 0xcf8-0xcfb in order
+         * to intercept 4 byte accesses.
+         */
+        for ( i = 0xcf8; i < 0xcfc; i++ )
+            __set_bit(i, d->arch.hvm_domain.io_bitmap);
     }
 }
 
-- 
1.9.5 (Apple Git-50.3)


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel