[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>

diff --git a/arch/sparc64/kernel/tsb.S b/arch/sparc64/kernel/tsb.S
index eedf94f..10adb2f 100644 (file)
--- a/arch/sparc64/kernel/tsb.S
+++ b/arch/sparc64/kernel/tsb.S
@@ -546,6 +546,7 @@ NGtsb_init:
        subcc           %o1, 0x100, %o1
        bne,pt          %xcc, 1b
         add            %o0, 0x100, %o0
+       membar          #Sync
        retl
         wr             %g2, 0x0, %asi
        .size           NGtsb_init, .-NGtsb_init

diff --git a/arch/sparc64/lib/NGbzero.S b/arch/sparc64/lib/NGbzero.S
index e86baec..f10e452 100644 (file)
--- 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:

diff --git a/arch/sparc64/lib/NGmemcpy.S b/arch/sparc64/lib/NGmemcpy.S
index 8e522b3..66063a9 100644 (file)
--- a/arch/sparc64/lib/NGmemcpy.S
+++ b/arch/sparc64/lib/NGmemcpy.S
@@ -247,6 +247,8 @@ FUNC_NAME:  /* %o0=dst, %o1=src, %o2=len */
        /* fall through */
 
 60:    
+       membar          #Sync
+
        /* %o2 contains any final bytes still needed to be copied
         * over. If anything is left, we copy it one byte at a time.
         */

diff --git a/arch/sparc64/lib/NGpage.S b/arch/sparc64/lib/NGpage.S
index 7d7c3bb..8ce3a0c 100644 (file)
--- a/arch/sparc64/lib/NGpage.S
+++ b/arch/sparc64/lib/NGpage.S
@@ -41,6 +41,7 @@ NGcopy_user_page:     /* %o0=dest, %o1=src, %o2=vaddr */
        subcc           %g7, 64, %g7
        bne,pt          %xcc, 1b
         add            %o0, 32, %o0
+       membar          #Sync
        retl
         nop
 
@@ -63,6 +64,7 @@ NGclear_user_page:    /* %o0=dest, %o1=vaddr */
        subcc           %g7, 64, %g7
        bne,pt          %xcc, 1b
         add            %o0, 32, %o0
+       membar          #Sync
        retl
         nop