[XEN][HVM] Initialise the ELCR so that all interrupts are in level triggered

mode after pic_reset, since that seems to be what Linux expects.

Signed-off-by: Steven Smith <sos22@cam.ac.uk>

diff --git a/xen/arch/x86/hvm/i8259.c b/xen/arch/x86/hvm/i8259.c
index f3c5aaffe8e04d6f733f17ee8394ace3aa45b2ac..4829f0dc0ee21f92c4f0493b0fd0d6c270774d7b 100644 (file)
--- a/xen/arch/x86/hvm/i8259.c
+++ b/xen/arch/x86/hvm/i8259.c
@@ -271,7 +271,10 @@ static void pic_reset(void *opaque)
     s->rotate_on_auto_eoi = 0;
     s->special_fully_nested_mode = 0;
     s->init4 = 0;
-    s->elcr = 0;
+
+    /* Initialise to level triggered mode, since Linux assumes that in
+       a few places and it doesn't appear to break anything. */
+    s->elcr = 0xff & s->elcr_mask;
 }
 
 /* Caller must hold vpic lock */