Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Nicholas Piggin <npiggin@gmail.com>
To:     linuxppc-dev@lists.ozlabs.org
Cc:     Nicholas Piggin <npiggin@gmail.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>, linux-kernel@vger.kernel.org
Subject: [PATCH 01/15] powerpc/powernv: opal_put_chars partial write fix
Date:   Tue,  1 May 2018 00:55:44 +1000
Message-Id: <20180430145558.4308-2-npiggin@gmail.com>
In-Reply-To: <20180430145558.4308-1-npiggin@gmail.com>
References: <20180430145558.4308-1-npiggin@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

The intention here is to consume and discard the remaining buffer
upon error. This works if there has not been a previous partial write.
If there has been, then total_len is no longer total number of bytes
to copy. total_len is always "bytes left to copy", so it should be
added to written bytes.

This code may not be exercised any more if partial writes will not be
hit, but this is a small bugfix before a larger change.

Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/platforms/powernv/opal.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index 48fbb41af5d1..e695b836fd49 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -388,7 +388,7 @@ int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
 		/* Closed or other error drop */
 		if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
 		    rc != OPAL_BUSY_EVENT) {
-			written = total_len;
+			written += total_len;
 			break;
 		}
 		if (rc == OPAL_SUCCESS) {
-- 
2.17.0