From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-sn1nam01on0109.outbound.protection.outlook.com ([104.47.32.109]:39556 "EHLO NAM01-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729100AbeIGFPD (ORCPT ); Fri, 7 Sep 2018 01:15:03 -0400 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Nicholas Piggin , Michael Ellerman , Sasha Levin Subject: [PATCH AUTOSEL 4.18 55/88] powerpc/powernv: opal_put_chars partial write fix Date: Fri, 7 Sep 2018 00:36:32 +0000 Message-ID: <20180907003547.57567-55-alexander.levin@microsoft.com> References: <20180907003547.57567-1-alexander.levin@microsoft.com> In-Reply-To: <20180907003547.57567-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org List-ID: From: Nicholas Piggin [ Upstream commit bd90284cc6c1c9e8e48c8eadd0c79574fcce0b81 ] 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 Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin --- 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 0d539c661748..371e33ecc547 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 !=3D OPAL_SUCCESS && rc !=3D OPAL_BUSY && rc !=3D OPAL_BUSY_EVENT) { - written =3D total_len; + written +=3D total_len; break; } if (rc =3D=3D OPAL_SUCCESS) { --=20 2.17.1