Reduce stack usage of hw irq handlers.

Avoid using call16_int() -- it consumes too much stack space.
    Instead, use a new function (call16_simpint).  This assumes that
    the handler wont corrupt regs - which should be a safe assumption,
    because if they did corrupt regs they wouldn't work on any bios.
Avoid enabling irqs in the hw irq handlers - there are no loops in the
    handlers that could cause any notable latency.

1 files changed, 2 insertions, 3 deletions

diff --git a/src/system.c b/src/system.c
index 235e88c9..47d58174 100644
--- a/src/system.c
+++ b/src/system.c
@@ -399,7 +399,6 @@ handle_75()
     // clear interrupt
     eoi_pic2();
     // legacy nmi call
-    struct bregs br;
-    memset(&br, 0, sizeof(br));
-    call16_int(0x02, &br);
+    u32 eax=0, flags;
+    call16_simpint(0x02, &eax, &flags);
 }