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Date: Wed, 6 Jul 2011 17:51:36 +1000
From: Anton Blanchard <anton@samba.org>
To: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Subject: [PATCH 2/2]: powerpc/pseries/hvconsole: Fix dropped console output
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Return -EAGAIN when we get H_BUSY back from the hypervisor. This
makes the hvc console driver retry, avoiding dropped printks.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
---

Index: linux-powerpc/arch/powerpc/platforms/pseries/hvconsole.c
===================================================================
--- linux-powerpc.orig/arch/powerpc/platforms/pseries/hvconsole.c	2011-07-06 17:11:33.799095935 +1000
+++ linux-powerpc/arch/powerpc/platforms/pseries/hvconsole.c	2011-07-06 17:11:47.499332962 +1000
@@ -73,7 +73,7 @@ int hvc_put_chars(uint32_t vtermno, cons
 	if (ret == H_SUCCESS)
 		return count;
 	if (ret == H_BUSY)
-		return 0;
+		return -EAGAIN;
 	return -EIO;
 }