From patchwork Fri Dec 6 12:57:42 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 297947 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 0D4062C0098 for ; Sat, 7 Dec 2013 00:13:36 +1100 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1VovDn-0007M8-5J; Fri, 06 Dec 2013 13:13:31 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1Vov3y-0000ur-0g for kernel-team@lists.ubuntu.com; Fri, 06 Dec 2013 13:03:22 +0000 Received: from bl20-223-32.dsl.telepac.pt ([2.81.223.32] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1Vov3x-0007ow-Q3; Fri, 06 Dec 2013 13:03:21 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.11 173/272] [media] tuner-xc2028: Don't use dynamic static allocation Date: Fri, 6 Dec 2013 12:57:42 +0000 Message-Id: <1386334761-25517-174-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> References: <1386334761-25517-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Cc: Mauro Carvalho Chehab X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.11.10.1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab commit 56ac033725ec93a45170caf3979eb2b1211a59a8 upstream. Dynamic static allocation is evil, as Kernel stack is too low, and compilation complains about it on some archs: drivers/media/tuners/tuner-xc2028.c:651:1: warning: 'load_firmware' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer. In the specific case of this driver, the maximum limit is 80, used only on tm6000 driver. This limit is due to the size of the USB control URBs. Ok, it would be theoretically possible to use a bigger size on PCI devices, but the firmware load time is already good enough. Anyway, if some usage requires more, it is just a matter of also increasing the buffer size at load_firmware(). Signed-off-by: Mauro Carvalho Chehab Reviewed-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Luis Henriques --- drivers/media/tuners/tuner-xc2028.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/media/tuners/tuner-xc2028.c b/drivers/media/tuners/tuner-xc2028.c index 878d2c4..9771cd8 100644 --- a/drivers/media/tuners/tuner-xc2028.c +++ b/drivers/media/tuners/tuner-xc2028.c @@ -24,6 +24,9 @@ #include #include "dvb_frontend.h" +/* Max transfer size done by I2C transfer functions */ +#define MAX_XFER_SIZE 80 + /* Registers (Write-only) */ #define XREG_INIT 0x00 #define XREG_RF_FREQ 0x02 @@ -547,7 +550,10 @@ static int load_firmware(struct dvb_frontend *fe, unsigned int type, { struct xc2028_data *priv = fe->tuner_priv; int pos, rc; - unsigned char *p, *endp, buf[priv->ctrl.max_len]; + unsigned char *p, *endp, buf[MAX_XFER_SIZE]; + + if (priv->ctrl.max_len > sizeof(buf)) + priv->ctrl.max_len = sizeof(buf); tuner_dbg("%s called\n", __func__);