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Date: Wed, 13 Apr 2016 09:44:31 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
 Anton Blanchard <anton@samba.org>
Cc: Jiri Slaby <jslaby@suse.com>,
 Paul Gortmaker <paul.gortmaker@windriver.com>,
 Peter Hurley <peter@hurleysoftware.com>,
 Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@lists.ozlabs.org,
 linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [patch] tty: hvc_console: silence unintialized variable warning
Message-ID: <20160413064431.GF8092@mwanda>
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If ->get_char() returns a negative error code and that can mean that
"ch" is uninitialized.  The callers of this function expect NO_POLL_CHAR
on error so let's return that.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index e46d628..325747a 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -814,7 +814,7 @@ static int hvc_poll_get_char(struct tty_driver *driver, int line)
 
 	n = hp->ops->get_chars(hp->vtermno, &ch, 1);
 
-	if (n == 0)
+	if (n <= 0)
 		return NO_POLL_CHAR;
 
 	return ch;