Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756436AbcJGNuw (ORCPT ); Fri, 7 Oct 2016 09:50:52 -0400 Received: from mail-vk0-f65.google.com ([209.85.213.65]:32946 "EHLO mail-vk0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753582AbcJGNum (ORCPT ); Fri, 7 Oct 2016 09:50:42 -0400 MIME-Version: 1.0 In-Reply-To: <20161006152905.2f9a9b13@vento.lan> References: <20161005155805.27dc4d33@vento.lan> <20161006152905.2f9a9b13@vento.lan> From: =?UTF-8?Q?J=C3=B6rg_Otte?= Date: Fri, 7 Oct 2016 15:50:40 +0200 Message-ID: Subject: Re: [PATCH v2] cinergyT2-core: don't do DMA on stack To: Mauro Carvalho Chehab Cc: Andy Lutomirski , Johannes Stezenbach , Jiri Kosina , Patrick Boettcher , Linux Kernel Mailing List , Andy Lutomirski , Michael Krufky , Mauro Carvalho Chehab , Linux Media Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id u97DotH5025227 Content-Length: 7590 Lines: 206 2016-10-06 20:29 GMT+02:00 Mauro Carvalho Chehab : > Em Thu, 6 Oct 2016 10:27:56 -0700 > Andy Lutomirski escreveu: > >> On Wed, Oct 5, 2016 at 11:58 AM, Mauro Carvalho Chehab >> wrote: >> > Sorry, forgot to C/C people that are at the "Re: Problem with VMAP_STACK=y" >> > thread. >> > >> > Forwarded message: >> > >> > Date: Wed, 5 Oct 2016 15:54:18 -0300 >> > From: Mauro Carvalho Chehab >> > To: Linux Doc Mailing List >> > Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , Mauro Carvalho Chehab >> > Subject: [PATCH v2] cinergyT2-core: don't do DMA on stack >> > >> > >> > 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 >> > --- >> > >> > Added the fixups made by Johannes Stezenbach >> > >> > drivers/media/usb/dvb-usb/cinergyT2-core.c | 45 ++++++++++++++++++------------ >> > 1 file changed, 27 insertions(+), 18 deletions(-) >> > >> > diff --git a/drivers/media/usb/dvb-usb/cinergyT2-core.c b/drivers/media/usb/dvb-usb/cinergyT2-core.c >> > index 9fd1527494eb..8267e3777af6 100644 >> > --- a/drivers/media/usb/dvb-usb/cinergyT2-core.c >> > +++ b/drivers/media/usb/dvb-usb/cinergyT2-core.c >> > @@ -41,6 +41,7 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr); >> > >> > struct cinergyt2_state { >> > u8 rc_counter; >> > + unsigned char data[64]; >> > }; >> > >> > /* We are missing a release hook with usb_device data */ >> > @@ -50,29 +51,36 @@ static struct dvb_usb_device_properties cinergyt2_properties; >> > >> > static int cinergyt2_streaming_ctrl(struct dvb_usb_adapter *adap, int enable) >> > { >> > - char buf[] = { CINERGYT2_EP1_CONTROL_STREAM_TRANSFER, enable ? 1 : 0 }; >> > - char result[64]; >> > - return dvb_usb_generic_rw(adap->dev, buf, sizeof(buf), result, >> > - sizeof(result), 0); >> > + struct dvb_usb_device *d = adap->dev; >> > + struct cinergyt2_state *st = d->priv; >> > + >> > + st->data[0] = CINERGYT2_EP1_CONTROL_STREAM_TRANSFER; >> > + st->data[1] = enable ? 1 : 0; >> > + >> > + return dvb_usb_generic_rw(d, st->data, 2, st->data, 64, 0); >> > } >> > >> > static int cinergyt2_power_ctrl(struct dvb_usb_device *d, int enable) >> > { >> >> This... >> >> > - char buf[] = { CINERGYT2_EP1_SLEEP_MODE, enable ? 0 : 1 }; >> > - char state[3]; >> > - return dvb_usb_generic_rw(d, buf, sizeof(buf), state, sizeof(state), 0); >> > + struct cinergyt2_state *st = d->priv; >> > + >> > + st->data[0] = CINERGYT2_EP1_SLEEP_MODE; >> >> ...does not match this: >> >> > + st->data[1] = enable ? 1 : 0; >> >> --Andy > > Gah! Yes. This is what happens when coding using cut-and-paste ;) > > Jörg, > > Please test it with the condition reversed with the enclosed patch. > > if this doesn't work, you can enable dvb-usb debug at runtime, > by loading it with debug parameter: > > parm: debug:set debugging level (1=info,xfer=2,pll=4,ts=8,err=16,rc=32,fw=64,mem=128,uxfer=256 (or-able)). (debugging is not enabled) (int) > > debug=2 should show the control messages sent to the device on dmesg. > > Regards, > Mauro > > > [PATCH] cinergyT2-core: don't do DMA on stack > > 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 > > diff --git a/drivers/media/usb/dvb-usb/cinergyT2-core.c b/drivers/media/usb/dvb-usb/cinergyT2-core.c > index 9fd1527494eb..91640c927776 100644 > --- a/drivers/media/usb/dvb-usb/cinergyT2-core.c > +++ b/drivers/media/usb/dvb-usb/cinergyT2-core.c > @@ -41,6 +41,7 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr); > > struct cinergyt2_state { > u8 rc_counter; > + unsigned char data[64]; > }; > > /* We are missing a release hook with usb_device data */ > @@ -50,29 +51,36 @@ static struct dvb_usb_device_properties cinergyt2_properties; > > static int cinergyt2_streaming_ctrl(struct dvb_usb_adapter *adap, int enable) > { > - char buf[] = { CINERGYT2_EP1_CONTROL_STREAM_TRANSFER, enable ? 1 : 0 }; > - char result[64]; > - return dvb_usb_generic_rw(adap->dev, buf, sizeof(buf), result, > - sizeof(result), 0); > + struct dvb_usb_device *d = adap->dev; > + struct cinergyt2_state *st = d->priv; > + > + st->data[0] = CINERGYT2_EP1_CONTROL_STREAM_TRANSFER; > + st->data[1] = enable ? 1 : 0; > + > + return dvb_usb_generic_rw(d, st->data, 2, st->data, 64, 0); > } > > static int cinergyt2_power_ctrl(struct dvb_usb_device *d, int enable) > { > - char buf[] = { CINERGYT2_EP1_SLEEP_MODE, enable ? 0 : 1 }; > - char state[3]; > - return dvb_usb_generic_rw(d, buf, sizeof(buf), state, sizeof(state), 0); > + struct cinergyt2_state *st = d->priv; > + > + st->data[0] = CINERGYT2_EP1_SLEEP_MODE; > + st->data[1] = enable ? 0 : 1; > + > + return dvb_usb_generic_rw(d, st->data, 2, st->data, 3, 0); > } > > static int cinergyt2_frontend_attach(struct dvb_usb_adapter *adap) > { > - char query[] = { CINERGYT2_EP1_GET_FIRMWARE_VERSION }; > - char state[3]; > + struct dvb_usb_device *d = adap->dev; > + struct cinergyt2_state *st = d->priv; > int ret; > > adap->fe_adap[0].fe = cinergyt2_fe_attach(adap->dev); > > - ret = dvb_usb_generic_rw(adap->dev, query, sizeof(query), state, > - sizeof(state), 0); > + st->data[0] = CINERGYT2_EP1_GET_FIRMWARE_VERSION; > + > + ret = dvb_usb_generic_rw(d, st->data, 1, st->data, 3, 0); > if (ret < 0) { > deb_rc("cinergyt2_power_ctrl() Failed to retrieve sleep " > "state info\n"); > @@ -141,13 +149,14 @@ static int repeatable_keys[] = { > static int cinergyt2_rc_query(struct dvb_usb_device *d, u32 *event, int *state) > { > struct cinergyt2_state *st = d->priv; > - u8 key[5] = {0, 0, 0, 0, 0}, cmd = CINERGYT2_EP1_GET_RC_EVENTS; > int i; > > *state = REMOTE_NO_KEY_PRESSED; > > - dvb_usb_generic_rw(d, &cmd, 1, key, sizeof(key), 0); > - if (key[4] == 0xff) { > + st->data[0] = CINERGYT2_EP1_GET_RC_EVENTS; > + > + dvb_usb_generic_rw(d, st->data, 1, st->data, 5, 0); > + if (st->data[4] == 0xff) { > /* key repeat */ > st->rc_counter++; > if (st->rc_counter > RC_REPEAT_DELAY) { > @@ -166,13 +175,13 @@ static int cinergyt2_rc_query(struct dvb_usb_device *d, u32 *event, int *state) > } > > /* hack to pass checksum on the custom field */ > - key[2] = ~key[1]; > - dvb_usb_nec_rc_key_to_event(d, key, event, state); > - if (key[0] != 0) { > + st->data[2] = ~st->data[1]; > + dvb_usb_nec_rc_key_to_event(d, st->data, event, state); > + if (st->data[0] != 0) { > if (*event != d->last_event) > st->rc_counter = 0; > > - deb_rc("key: %*ph\n", 5, key); > + deb_rc("key: %*ph\n", 5, st->data); > } > return 0; > } > > > > Thanks, > Mauro Patch works for me! Thanks, Jörg