[SPARC64]: store-init needs trailing membar.

The manual says that it is required and we actually have crash reports
where loads see stale data due to not having membars here.

In one case the networking does:

	memset(skb, 0, offsetof(struct sk_buff, truesize));

and then some code later checks skb->nohdr for zero, but it's still
the value that was there before the memset().

Note that arch/sparc64/lib/xor.S already got this right.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/sparc64/lib/NGbzero.S b/arch/sparc64/lib/NGbzero.S
index e86baece5cc8..f10e4529ee37 100644
--- a/arch/sparc64/lib/NGbzero.S
+++ b/arch/sparc64/lib/NGbzero.S
@@ -88,6 +88,7 @@ NGbzero_loop:
         bne,pt          %xcc, NGbzero_loop
          add            %o0, 64, %o0
 
+        membar          #Sync
         wr              %o4, 0x0, %asi
         brz,pn          %o1, NGbzero_done
 NGbzero_medium: