[patch 1/3] sgi-xpc: ensure flags are updated before bte_copy

[holt]

From: Robin Holt <holt@xxxxxxx>

The clearing of the msg->flags needs a barrier between it and the notify
of the channel threads that the messages are cleaned and ready for use.

Signed-off-by: Robin Holt <holt@xxxxxxx>
Signed-off-by: Dean Nelson <dcn@xxxxxxx>
Cc: <stable@xxxxxxxxxx>

---

 drivers/misc/sgi-xp/xpc_sn2.c |    1 +
 1 file changed, 1 insertion(+)
Index: xpc-fixes-20090115/drivers/misc/sgi-xp/xpc_sn2.c
===================================================================
--- xpc-fixes-20090115.orig/drivers/misc/sgi-xp/xpc_sn2.c	2009-01-15 10:21:53.700266968 -0600
+++ xpc-fixes-20090115/drivers/misc/sgi-xp/xpc_sn2.c	2009-01-15 10:51:10.165613058 -0600
@@ -1836,6 +1836,7 @@ xpc_process_msg_chctl_flags_sn2(struct x
 		 */
 		xpc_clear_remote_msgqueue_flags_sn2(ch);
 
+		wmb();	/* ensure flags have been cleared before bte_copy */
 		ch_sn2->w_remote_GP.put = ch_sn2->remote_GP.put;
 
 		dev_dbg(xpc_chan, "w_remote_GP.put changed to %ld, partid=%d, "

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/