2 files changed, 9 insertions, 2 deletions

diff --git a/arch/i386/boot/tty.c b/arch/i386/boot/tty.c
index a8db78736b02..9c668aad3515 100644
--- a/arch/i386/boot/tty.c
+++ b/arch/i386/boot/tty.c
@@ -31,7 +31,7 @@ void __attribute__((section(".inittext"))) putchar(int ch)
 
         /* int $0x10 is known to have bugs involving touching registers
            it shouldn't.  Be extra conservative... */
-        asm volatile("pushal; int $0x10; popal"
+        asm volatile("pushal; pushw %%ds; int $0x10; popw %%ds; popal"
                      : : "b" (0x0007), "c" (0x0001), "a" (0x0e00|ch));
 }
 
diff --git a/arch/i386/boot/video.h b/arch/i386/boot/video.h
index 29eca1710b2c..b92447d51213 100644
--- a/arch/i386/boot/video.h
+++ b/arch/i386/boot/video.h
@@ -117,8 +117,15 @@ extern int graphic_mode;	/* Graphics mode with linear frame buffer */
  * int $0x10 is notorious for touching registers it shouldn't.
  * gcc doesn't like %ebp being clobbered, so define it as a push/pop
  * sequence here.
+ *
+ * A number of systems, including the original PC can clobber %bp in
+ * certain circumstances, like when scrolling.  There exists at least
+ * one Trident video card which could clobber DS under a set of
+ * circumstances that we are unlikely to encounter (scrolling when
+ * using an extended graphics mode of more than 800x600 pixels), but
+ * it's cheap insurance to deal with that here.
  */
-#define INT10 "pushl %%ebp; int $0x10; popl %%ebp"
+#define INT10 "pushl %%ebp; pushw %%ds; int $0x10; popw %%ds; popl %%ebp"
 
 /* Accessing VGA indexed registers */
 static inline u8 in_idx(u16 port, u8 index)