[Qemu-devel] [PATCH] xen: avoid tracking the region 0xa0000 - 0xbffff

[stefano.stabellini]

From: Stefano Stabellini <address@hidden>

Xen can only do dirty bit tracking for one memory region, so we should
explicitly avoid trying to track the legacy VGA region between 0xa0000
and 0xbffff, rather than trying and failing.

Signed-off-by: Stefano Stabellini <address@hidden>
---
 xen-all.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/xen-all.c b/xen-all.c
index 9a5c3ec..1fdc2e8 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -218,6 +218,10 @@ static int xen_add_to_physmap(XenIOState *state,
     if (get_physmapping(state, start_addr, size)) {
         return 0;
     }
+    /* do not try to map legacy VGA memory */
+    if (start_addr >= 0xa0000 && start_addr + size <= 0xbffff) {
+        return -1;
+    }
     if (size <= 0) {
         return -1;
     }
-- 
1.7.2.3