[IA64] fix csum_ipv6_magic()

The 32-bit parameters (len and csum) of csum_ipv6_magic() are passed in 64-bit
registers in2 and in4. The high order 32 bits of the registers were never
cleared, and garbage was sometimes calculated into the checksum.

Fix this by clearing the high order 32 bits of these registers.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/arch/ia64/lib/ip_fast_csum.S b/arch/ia64/lib/ip_fast_csum.S
index 1f86aeb2c948..620d9dc5220f 100644
--- a/arch/ia64/lib/ip_fast_csum.S
+++ b/arch/ia64/lib/ip_fast_csum.S
@@ -96,20 +96,22 @@ END(ip_fast_csum)
 GLOBAL_ENTRY(csum_ipv6_magic)
         ld4     r20=[in0],4
         ld4     r21=[in1],4
-        dep     r15=in3,in2,32,16
+        zxt4    in2=in2
         ;;
         ld4     r22=[in0],4
         ld4     r23=[in1],4
-        mux1    r15=r15,@rev
+        dep     r15=in3,in2,32,16
         ;;
         ld4     r24=[in0],4
         ld4     r25=[in1],4
-        shr.u   r15=r15,16
+        mux1    r15=r15,@rev
         add     r16=r20,r21
         add     r17=r22,r23
+        zxt4    in4=in4
         ;;
         ld4     r26=[in0],4
         ld4     r27=[in1],4
+        shr.u   r15=r15,16
         add     r18=r24,r25
         add     r8=r16,r17
         ;;