Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964917AbcJGRZK (ORCPT ); Fri, 7 Oct 2016 13:25:10 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:46772 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935118AbcJGRYq (ORCPT ); Fri, 7 Oct 2016 13:24:46 -0400 From: Mauro Carvalho Chehab To: Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , Andy Lutomirski , Johannes Stezenbach , Jiri Kosina , Patrick Boettcher , Linux Kernel Mailing List , Andy Lutomirski , Michael Krufky , Mauro Carvalho Chehab , =?UTF-8?q?J=C3=B6rg=20Otte?= Subject: [PATCH 11/26] digitv: don't do DMA on stack Date: Fri, 7 Oct 2016 14:24:21 -0300 Message-Id: <0ab236ba1bfe2935b2cda329b706fcc1ef55edeb.1475860773.git.mchehab@s-opensource.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1912 Lines: 63 The USB control messages require DMA to work. We cannot pass a stack-allocated buffer, as it is not warranted that the stack would be into a DMA enabled area. Signed-off-by: Mauro Carvalho Chehab --- drivers/media/usb/dvb-usb/digitv.c | 20 +++++++++++--------- drivers/media/usb/dvb-usb/digitv.h | 3 +++ 2 files changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/media/usb/dvb-usb/digitv.c b/drivers/media/usb/dvb-usb/digitv.c index 63134335c994..09f8c28bd4db 100644 --- a/drivers/media/usb/dvb-usb/digitv.c +++ b/drivers/media/usb/dvb-usb/digitv.c @@ -28,20 +28,22 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr); static int digitv_ctrl_msg(struct dvb_usb_device *d, u8 cmd, u8 vv, u8 *wbuf, int wlen, u8 *rbuf, int rlen) { + struct digitv_state *st = d->priv; int wo = (rbuf == NULL || rlen == 0); /* write-only */ - u8 sndbuf[7],rcvbuf[7]; - memset(sndbuf,0,7); memset(rcvbuf,0,7); - sndbuf[0] = cmd; - sndbuf[1] = vv; - sndbuf[2] = wo ? wlen : rlen; + memset(st->sndbuf, 0, 7); + memset(st->rcvbuf, 0, 7); + + st->sndbuf[0] = cmd; + st->sndbuf[1] = vv; + st->sndbuf[2] = wo ? wlen : rlen; if (wo) { - memcpy(&sndbuf[3],wbuf,wlen); - dvb_usb_generic_write(d,sndbuf,7); + memcpy(&st->sndbuf[3], wbuf, wlen); + dvb_usb_generic_write(d, st->sndbuf, 7); } else { - dvb_usb_generic_rw(d,sndbuf,7,rcvbuf,7,10); - memcpy(rbuf,&rcvbuf[3],rlen); + dvb_usb_generic_rw(d, st->sndbuf, 7, st->rcvbuf, 7, 10); + memcpy(rbuf, &st->rcvbuf[3], rlen); } return 0; } diff --git a/drivers/media/usb/dvb-usb/digitv.h b/drivers/media/usb/dvb-usb/digitv.h index 908c09f4966b..cf104689bdff 100644 --- a/drivers/media/usb/dvb-usb/digitv.h +++ b/drivers/media/usb/dvb-usb/digitv.h @@ -6,6 +6,9 @@ struct digitv_state { int is_nxt6000; + + unsigned char sndbuf[7]; + unsigned char rcvbuf[7]; }; /* protocol (from usblogging and the SDK: -- 2.7.4