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* [PATCH] em28xx: split up em28xx_dvb_init to reduce stack size
@ 2017-12-11 12:05 Arnd Bergmann
  2017-12-14 17:10 ` Mauro Carvalho Chehab
  0 siblings, 1 reply; 3+ messages in thread
From: Arnd Bergmann @ 2017-12-11 12:05 UTC (permalink / raw)
  To: Mauro Carvalho Chehab
  Cc: Arnd Bergmann, Kevin Cheng, linux-media, linux-kernel

With CONFIG_KASAN, the init function uses a large amount of kernel stack:

drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init.part.4':
drivers/media/usb/em28xx/em28xx-dvb.c:2061:1: error: the frame size of 3232 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]

Using gcc-7 with -fsanitize-address-use-after-scope makes this even worse:

drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init':
drivers/media/usb/em28xx/em28xx-dvb.c:2069:1: error: the frame size of 4280 bytes is larger than 3072 bytes [-Werror=frame-larger-than=]

By splitting out each part of the switch/case statement that has its own local
variables into a separate function, no single one of them uses more than 500 bytes,
and with a noinline_for_stack annotation we can ensure that they are not merged
back together.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/media/usb/em28xx/em28xx-dvb.c | 947 ++++++++++++++++++----------------
 1 file changed, 508 insertions(+), 439 deletions(-)

diff --git a/drivers/media/usb/em28xx/em28xx-dvb.c b/drivers/media/usb/em28xx/em28xx-dvb.c
index 9950a740e04e..6665885dbaa7 100644
--- a/drivers/media/usb/em28xx/em28xx-dvb.c
+++ b/drivers/media/usb/em28xx/em28xx-dvb.c
@@ -934,7 +934,7 @@ static struct lgdt3306a_config hauppauge_01595_lgdt3306a_config = {
 
 /* ------------------------------------------------------------------ */
 
-static int em28xx_attach_xc3028(u8 addr, struct em28xx *dev)
+static noinline_for_stack int em28xx_attach_xc3028(u8 addr, struct em28xx *dev)
 {
 	struct dvb_frontend *fe;
 	struct xc2028_config cfg;
@@ -1126,6 +1126,492 @@ static void em28xx_unregister_dvb(struct em28xx_dvb *dvb)
 	dvb_unregister_adapter(&dvb->adapter);
 }
 
+static noinline_for_stack int em28174_dvb_init_pctv_460e(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_client *client;
+	struct i2c_board_info board_info;
+	struct tda10071_platform_data tda10071_pdata = {};
+	struct a8293_platform_data a8293_pdata = {};
+	int result;
+
+	/* attach demod + tuner combo */
+	tda10071_pdata.clk = 40444000, /* 40.444 MHz */
+	tda10071_pdata.i2c_wr_max = 64,
+	tda10071_pdata.ts_mode = TDA10071_TS_SERIAL,
+	tda10071_pdata.pll_multiplier = 20,
+	tda10071_pdata.tuner_i2c_addr = 0x14,
+	memset(&board_info, 0, sizeof(board_info));
+	strlcpy(board_info.type, "tda10071_cx24118", I2C_NAME_SIZE);
+	board_info.addr = 0x55;
+	board_info.platform_data = &tda10071_pdata;
+	request_module("tda10071");
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->fe[0] = tda10071_pdata.get_dvb_frontend(client);
+	dvb->i2c_client_demod = client;
+
+	/* attach SEC */
+	a8293_pdata.dvb_frontend = dvb->fe[0];
+	memset(&board_info, 0, sizeof(board_info));
+	strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
+	board_info.addr = 0x08;
+	board_info.platform_data = &a8293_pdata;
+	request_module("a8293");
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->i2c_client_sec = client;
+	result = 0;
+out_free:
+	return result;
+}
+
+static noinline_for_stack int em28178_dvb_init_pctv_461e(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_client *client;
+	struct i2c_adapter *i2c_adapter;
+	struct i2c_board_info board_info;
+	struct m88ds3103_platform_data m88ds3103_pdata = {};
+	struct ts2020_config ts2020_config = {};
+	struct a8293_platform_data a8293_pdata = {};
+	int result;
+
+	/* attach demod */
+	m88ds3103_pdata.clk = 27000000;
+	m88ds3103_pdata.i2c_wr_max = 33;
+	m88ds3103_pdata.ts_mode = M88DS3103_TS_PARALLEL;
+	m88ds3103_pdata.ts_clk = 16000;
+	m88ds3103_pdata.ts_clk_pol = 1;
+	m88ds3103_pdata.agc = 0x99;
+	memset(&board_info, 0, sizeof(board_info));
+	strlcpy(board_info.type, "m88ds3103", I2C_NAME_SIZE);
+	board_info.addr = 0x68;
+	board_info.platform_data = &m88ds3103_pdata;
+	request_module("m88ds3103");
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->fe[0] = m88ds3103_pdata.get_dvb_frontend(client);
+	i2c_adapter = m88ds3103_pdata.get_i2c_adapter(client);
+	dvb->i2c_client_demod = client;
+
+	/* attach tuner */
+	ts2020_config.fe = dvb->fe[0];
+	memset(&board_info, 0, sizeof(board_info));
+	strlcpy(board_info.type, "ts2022", I2C_NAME_SIZE);
+	board_info.addr = 0x60;
+	board_info.platform_data = &ts2020_config;
+	request_module("ts2020");
+	client = i2c_new_device(i2c_adapter, &board_info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->i2c_client_tuner = client;
+	/* delegate signal strength measurement to tuner */
+	dvb->fe[0]->ops.read_signal_strength =
+			dvb->fe[0]->ops.tuner_ops.get_rf_strength;
+
+	/* attach SEC */
+	a8293_pdata.dvb_frontend = dvb->fe[0];
+	memset(&board_info, 0, sizeof(board_info));
+	strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
+	board_info.addr = 0x08;
+	board_info.platform_data = &a8293_pdata;
+	request_module("a8293");
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_tuner->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_tuner);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_tuner->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_tuner);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->i2c_client_sec = client;
+	result = 0;
+out_free:
+	return result;
+}
+
+static noinline_for_stack int em28178_dvb_init_pctv_292e(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_adapter *adapter;
+	struct i2c_client *client;
+	struct i2c_board_info info;
+	struct si2168_config si2168_config;
+	struct si2157_config si2157_config;
+	int result;
+
+	/* attach demod */
+	memset(&si2168_config, 0, sizeof(si2168_config));
+	si2168_config.i2c_adapter = &adapter;
+	si2168_config.fe = &dvb->fe[0];
+	si2168_config.ts_mode = SI2168_TS_PARALLEL;
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2168", I2C_NAME_SIZE);
+	info.addr = 0x64;
+	info.platform_data = &si2168_config;
+	request_module(info.type);
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_demod = client;
+
+	/* attach tuner */
+	memset(&si2157_config, 0, sizeof(si2157_config));
+	si2157_config.fe = dvb->fe[0];
+	si2157_config.if_port = 1;
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+	si2157_config.mdev = dev->media_dev;
+#endif
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2157", I2C_NAME_SIZE);
+	info.addr = 0x60;
+	info.platform_data = &si2157_config;
+	request_module(info.type);
+	client = i2c_new_device(adapter, &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_tuner = client;
+	dvb->fe[0]->ops.set_lna = em28xx_pctv_292e_set_lna;
+	result = 0;
+out_free:
+	return result;
+}
+
+static noinline_for_stack int em28178_dvb_init_terratec_t2_stick_hd(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_adapter *adapter;
+	struct i2c_client *client;
+	struct i2c_board_info info;
+	struct si2168_config si2168_config;
+	struct si2157_config si2157_config;
+	int result;
+
+	/* attach demod */
+	memset(&si2168_config, 0, sizeof(si2168_config));
+	si2168_config.i2c_adapter = &adapter;
+	si2168_config.fe = &dvb->fe[0];
+	si2168_config.ts_mode = SI2168_TS_PARALLEL;
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2168", I2C_NAME_SIZE);
+	info.addr = 0x64;
+	info.platform_data = &si2168_config;
+	request_module(info.type);
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_demod = client;
+
+	/* attach tuner */
+	memset(&si2157_config, 0, sizeof(si2157_config));
+	si2157_config.fe = dvb->fe[0];
+	si2157_config.if_port = 0;
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+	si2157_config.mdev = dev->media_dev;
+#endif
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2146", I2C_NAME_SIZE);
+	info.addr = 0x60;
+	info.platform_data = &si2157_config;
+	request_module("si2157");
+	client = i2c_new_device(adapter, &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_tuner = client;
+	result = 0;
+out_free:
+	return result;
+}
+
+static noinline_for_stack int em28178_dvb_init_plex_px_bcud(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_client *client;
+	struct i2c_board_info info;
+	struct tc90522_config tc90522_config;
+	struct qm1d1c0042_config qm1d1c0042_config;
+	int result;
+
+	/* attach demod */
+	memset(&tc90522_config, 0, sizeof(tc90522_config));
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "tc90522sat", I2C_NAME_SIZE);
+	info.addr = 0x15;
+	info.platform_data = &tc90522_config;
+	request_module("tc90522");
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->i2c_client_demod = client;
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	/* attach tuner */
+	memset(&qm1d1c0042_config, 0,
+	       sizeof(qm1d1c0042_config));
+	qm1d1c0042_config.fe = tc90522_config.fe;
+	qm1d1c0042_config.lpf = 1;
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "qm1d1c0042", I2C_NAME_SIZE);
+	info.addr = 0x61;
+	info.platform_data = &qm1d1c0042_config;
+	request_module(info.type);
+	client = i2c_new_device(tc90522_config.tuner_i2c,
+				&info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->i2c_client_tuner = client;
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	dvb->fe[0] = tc90522_config.fe;
+	px_bcud_init(dev);
+	result = 0;
+out_free:
+	return result;
+}
+
+static noinline_for_stack int em28174_dvb_init_hauppauge_wintv_dualhd_dvb(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_adapter *adapter;
+	struct i2c_client *client;
+	struct i2c_board_info info;
+	struct si2168_config si2168_config;
+	struct si2157_config si2157_config;
+	int result;
+
+	/* attach demod */
+	memset(&si2168_config, 0, sizeof(si2168_config));
+	si2168_config.i2c_adapter = &adapter;
+	si2168_config.fe = &dvb->fe[0];
+	si2168_config.ts_mode = SI2168_TS_SERIAL;
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2168", I2C_NAME_SIZE);
+	info.addr = 0x64;
+	info.platform_data = &si2168_config;
+	request_module(info.type);
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_demod = client;
+
+	/* attach tuner */
+	memset(&si2157_config, 0, sizeof(si2157_config));
+	si2157_config.fe = dvb->fe[0];
+	si2157_config.if_port = 1;
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+	si2157_config.mdev = dev->media_dev;
+#endif
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2157", I2C_NAME_SIZE);
+	info.addr = 0x60;
+	info.platform_data = &si2157_config;
+	request_module(info.type);
+	client = i2c_new_device(adapter, &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_tuner = client;
+	result = 0;
+out_free:
+	return result;
+}
+
+static int em28174_dvb_init_hauppauge_wintv_dualhd_01595(struct em28xx *dev)
+{
+	struct em28xx_dvb *dvb = dev->dvb;
+	struct i2c_adapter *adapter;
+	struct i2c_client *client;
+	struct i2c_board_info info = {};
+	struct lgdt3306a_config lgdt3306a_config;
+	struct si2157_config si2157_config = {};
+	int result;
+
+	/* attach demod */
+	lgdt3306a_config = hauppauge_01595_lgdt3306a_config;
+	lgdt3306a_config.fe = &dvb->fe[0];
+	lgdt3306a_config.i2c_adapter = &adapter;
+	strlcpy(info.type, "lgdt3306a", sizeof(info.type));
+	info.addr = 0x59;
+	info.platform_data = &lgdt3306a_config;
+	request_module(info.type);
+	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus],
+			&info);
+	if (client == NULL || client->dev.driver == NULL) {
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_demod = client;
+
+	/* attach tuner */
+	si2157_config.fe = dvb->fe[0];
+	si2157_config.if_port = 1;
+	si2157_config.inversion = 1;
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+	si2157_config.mdev = dev->media_dev;
+#endif
+	memset(&info, 0, sizeof(struct i2c_board_info));
+	strlcpy(info.type, "si2157", sizeof(info.type));
+	info.addr = 0x60;
+	info.platform_data = &si2157_config;
+	request_module(info.type);
+
+	client = i2c_new_device(adapter, &info);
+	if (client == NULL || client->dev.driver == NULL) {
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+	if (!try_module_get(client->dev.driver->owner)) {
+		i2c_unregister_device(client);
+		module_put(dvb->i2c_client_demod->dev.driver->owner);
+		i2c_unregister_device(dvb->i2c_client_demod);
+		result = -ENODEV;
+		goto out_free;
+	}
+
+	dvb->i2c_client_tuner = client;
+	result = 0;
+out_free:
+	return result;
+}
 static int em28xx_dvb_init(struct em28xx *dev)
 {
 	int result = 0;
@@ -1427,60 +1913,11 @@ static int em28xx_dvb_init(struct em28xx *dev)
 				   &dev->i2c_adap[dev->def_i2c_bus],
 				   &c3tech_duo_tda18271_config);
 		break;
-	case EM28174_BOARD_PCTV_460E: {
-		struct i2c_client *client;
-		struct i2c_board_info board_info;
-		struct tda10071_platform_data tda10071_pdata = {};
-		struct a8293_platform_data a8293_pdata = {};
-
-		/* attach demod + tuner combo */
-		tda10071_pdata.clk = 40444000, /* 40.444 MHz */
-		tda10071_pdata.i2c_wr_max = 64,
-		tda10071_pdata.ts_mode = TDA10071_TS_SERIAL,
-		tda10071_pdata.pll_multiplier = 20,
-		tda10071_pdata.tuner_i2c_addr = 0x14,
-		memset(&board_info, 0, sizeof(board_info));
-		strlcpy(board_info.type, "tda10071_cx24118", I2C_NAME_SIZE);
-		board_info.addr = 0x55;
-		board_info.platform_data = &tda10071_pdata;
-		request_module("tda10071");
-		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
-		if (client == NULL || client->dev.driver == NULL) {
-			result = -ENODEV;
-			goto out_free;
-		}
-		if (!try_module_get(client->dev.driver->owner)) {
-			i2c_unregister_device(client);
-			result = -ENODEV;
-			goto out_free;
-		}
-		dvb->fe[0] = tda10071_pdata.get_dvb_frontend(client);
-		dvb->i2c_client_demod = client;
-
-		/* attach SEC */
-		a8293_pdata.dvb_frontend = dvb->fe[0];
-		memset(&board_info, 0, sizeof(board_info));
-		strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
-		board_info.addr = 0x08;
-		board_info.platform_data = &a8293_pdata;
-		request_module("a8293");
-		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
-		if (client == NULL || client->dev.driver == NULL) {
-			module_put(dvb->i2c_client_demod->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_demod);
-			result = -ENODEV;
+	case EM28174_BOARD_PCTV_460E:
+		result = em28174_dvb_init_pctv_460e(dev);
+		if (result)
 			goto out_free;
-		}
-		if (!try_module_get(client->dev.driver->owner)) {
-			i2c_unregister_device(client);
-			module_put(dvb->i2c_client_demod->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_demod);
-			result = -ENODEV;
-			goto out_free;
-		}
-		dvb->i2c_client_sec = client;
 		break;
-	}
 	case EM2874_BOARD_DELOCK_61959:
 	case EM2874_BOARD_MAXMEDIA_UB425_TC:
 		/* attach demodulator */
@@ -1627,403 +2064,35 @@ static int em28xx_dvb_init(struct em28xx *dev)
 			}
 		}
 		break;
-	case EM28178_BOARD_PCTV_461E: {
-		struct i2c_client *client;
-		struct i2c_adapter *i2c_adapter;
-		struct i2c_board_info board_info;
-		struct m88ds3103_platform_data m88ds3103_pdata = {};
-		struct ts2020_config ts2020_config = {};
-		struct a8293_platform_data a8293_pdata = {};
-
-		/* attach demod */
-		m88ds3103_pdata.clk = 27000000;
-		m88ds3103_pdata.i2c_wr_max = 33;
-		m88ds3103_pdata.ts_mode = M88DS3103_TS_PARALLEL;
-		m88ds3103_pdata.ts_clk = 16000;
-		m88ds3103_pdata.ts_clk_pol = 1;
-		m88ds3103_pdata.agc = 0x99;
-		memset(&board_info, 0, sizeof(board_info));
-		strlcpy(board_info.type, "m88ds3103", I2C_NAME_SIZE);
-		board_info.addr = 0x68;
-		board_info.platform_data = &m88ds3103_pdata;
-		request_module("m88ds3103");
-		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
-		if (client == NULL || client->dev.driver == NULL) {
-			result = -ENODEV;
+	case EM28178_BOARD_PCTV_461E: 
+		result = em28178_dvb_init_pctv_461e(dev);
+		if (result)
 			goto out_free;
-		}
-		if (!try_module_get(client->dev.driver->owner)) {
-			i2c_unregister_device(client);
-			result = -ENODEV;
-			goto out_free;
-		}
-		dvb->fe[0] = m88ds3103_pdata.get_dvb_frontend(client);
-		i2c_adapter = m88ds3103_pdata.get_i2c_adapter(client);
-		dvb->i2c_client_demod = client;
-
-		/* attach tuner */
-		ts2020_config.fe = dvb->fe[0];
-		memset(&board_info, 0, sizeof(board_info));
-		strlcpy(board_info.type, "ts2022", I2C_NAME_SIZE);
-		board_info.addr = 0x60;
-		board_info.platform_data = &ts2020_config;
-		request_module("ts2020");
-		client = i2c_new_device(i2c_adapter, &board_info);
-		if (client == NULL || client->dev.driver == NULL) {
-			module_put(dvb->i2c_client_demod->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_demod);
-			result = -ENODEV;
-			goto out_free;
-		}
-		if (!try_module_get(client->dev.driver->owner)) {
-			i2c_unregister_device(client);
-			module_put(dvb->i2c_client_demod->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_demod);
-			result = -ENODEV;
-			goto out_free;
-		}
-		dvb->i2c_client_tuner = client;
-		/* delegate signal strength measurement to tuner */
-		dvb->fe[0]->ops.read_signal_strength =
-				dvb->fe[0]->ops.tuner_ops.get_rf_strength;
-
-		/* attach SEC */
-		a8293_pdata.dvb_frontend = dvb->fe[0];
-		memset(&board_info, 0, sizeof(board_info));
-		strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
-		board_info.addr = 0x08;
-		board_info.platform_data = &a8293_pdata;
-		request_module("a8293");
-		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
-		if (client == NULL || client->dev.driver == NULL) {
-			module_put(dvb->i2c_client_tuner->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_tuner);
-			module_put(dvb->i2c_client_demod->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_demod);
-			result = -ENODEV;
-			goto out_free;
-		}
-		if (!try_module_get(client->dev.driver->owner)) {
-			i2c_unregister_device(client);
-			module_put(dvb->i2c_client_tuner->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_tuner);
-			module_put(dvb->i2c_client_demod->dev.driver->owner);
-			i2c_unregister_device(dvb->i2c_client_demod);
-			result = -ENODEV;
-			goto out_free;
-		}
-		dvb->i2c_client_sec = client;
 		break;
-	}
 	case EM28178_BOARD_PCTV_292E:
-		{
-			struct i2c_adapter *adapter;
-			struct i2c_client *client;
-			struct i2c_board_info info;
-			struct si2168_config si2168_config;
-			struct si2157_config si2157_config;
-
-			/* attach demod */
-			memset(&si2168_config, 0, sizeof(si2168_config));
-			si2168_config.i2c_adapter = &adapter;
-			si2168_config.fe = &dvb->fe[0];
-			si2168_config.ts_mode = SI2168_TS_PARALLEL;
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2168", I2C_NAME_SIZE);
-			info.addr = 0x64;
-			info.platform_data = &si2168_config;
-			request_module(info.type);
-			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_demod = client;
-
-			/* attach tuner */
-			memset(&si2157_config, 0, sizeof(si2157_config));
-			si2157_config.fe = dvb->fe[0];
-			si2157_config.if_port = 1;
-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
-			si2157_config.mdev = dev->media_dev;
-#endif
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2157", I2C_NAME_SIZE);
-			info.addr = 0x60;
-			info.platform_data = &si2157_config;
-			request_module(info.type);
-			client = i2c_new_device(adapter, &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_tuner = client;
-			dvb->fe[0]->ops.set_lna = em28xx_pctv_292e_set_lna;
-		}
+		result = em28178_dvb_init_pctv_292e(dev);
+		if (result)
+			goto out_free;
 		break;
 	case EM28178_BOARD_TERRATEC_T2_STICK_HD:
-		{
-			struct i2c_adapter *adapter;
-			struct i2c_client *client;
-			struct i2c_board_info info;
-			struct si2168_config si2168_config;
-			struct si2157_config si2157_config;
-
-			/* attach demod */
-			memset(&si2168_config, 0, sizeof(si2168_config));
-			si2168_config.i2c_adapter = &adapter;
-			si2168_config.fe = &dvb->fe[0];
-			si2168_config.ts_mode = SI2168_TS_PARALLEL;
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2168", I2C_NAME_SIZE);
-			info.addr = 0x64;
-			info.platform_data = &si2168_config;
-			request_module(info.type);
-			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_demod = client;
-
-			/* attach tuner */
-			memset(&si2157_config, 0, sizeof(si2157_config));
-			si2157_config.fe = dvb->fe[0];
-			si2157_config.if_port = 0;
-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
-			si2157_config.mdev = dev->media_dev;
-#endif
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2146", I2C_NAME_SIZE);
-			info.addr = 0x60;
-			info.platform_data = &si2157_config;
-			request_module("si2157");
-			client = i2c_new_device(adapter, &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_tuner = client;
-		}
+		result = em28178_dvb_init_terratec_t2_stick_hd(dev);
+		if (result)
+			goto out_free;
 		break;
-
 	case EM28178_BOARD_PLEX_PX_BCUD:
-		{
-			struct i2c_client *client;
-			struct i2c_board_info info;
-			struct tc90522_config tc90522_config;
-			struct qm1d1c0042_config qm1d1c0042_config;
-
-			/* attach demod */
-			memset(&tc90522_config, 0, sizeof(tc90522_config));
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "tc90522sat", I2C_NAME_SIZE);
-			info.addr = 0x15;
-			info.platform_data = &tc90522_config;
-			request_module("tc90522");
-			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				result = -ENODEV;
-				goto out_free;
-			}
-			dvb->i2c_client_demod = client;
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			/* attach tuner */
-			memset(&qm1d1c0042_config, 0,
-			       sizeof(qm1d1c0042_config));
-			qm1d1c0042_config.fe = tc90522_config.fe;
-			qm1d1c0042_config.lpf = 1;
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "qm1d1c0042", I2C_NAME_SIZE);
-			info.addr = 0x61;
-			info.platform_data = &qm1d1c0042_config;
-			request_module(info.type);
-			client = i2c_new_device(tc90522_config.tuner_i2c,
-						&info);
-			if (client == NULL || client->dev.driver == NULL) {
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-			dvb->i2c_client_tuner = client;
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-			dvb->fe[0] = tc90522_config.fe;
-			px_bcud_init(dev);
-		}
+		result = em28178_dvb_init_plex_px_bcud(dev);
+		if (result)
+			goto out_free;
 		break;
 	case EM28174_BOARD_HAUPPAUGE_WINTV_DUALHD_DVB:
-		{
-			struct i2c_adapter *adapter;
-			struct i2c_client *client;
-			struct i2c_board_info info;
-			struct si2168_config si2168_config;
-			struct si2157_config si2157_config;
-
-			/* attach demod */
-			memset(&si2168_config, 0, sizeof(si2168_config));
-			si2168_config.i2c_adapter = &adapter;
-			si2168_config.fe = &dvb->fe[0];
-			si2168_config.ts_mode = SI2168_TS_SERIAL;
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2168", I2C_NAME_SIZE);
-			info.addr = 0x64;
-			info.platform_data = &si2168_config;
-			request_module(info.type);
-			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_demod = client;
-
-			/* attach tuner */
-			memset(&si2157_config, 0, sizeof(si2157_config));
-			si2157_config.fe = dvb->fe[0];
-			si2157_config.if_port = 1;
-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
-			si2157_config.mdev = dev->media_dev;
-#endif
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2157", I2C_NAME_SIZE);
-			info.addr = 0x60;
-			info.platform_data = &si2157_config;
-			request_module(info.type);
-			client = i2c_new_device(adapter, &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_tuner = client;
-
-		}
+		result = em28174_dvb_init_hauppauge_wintv_dualhd_dvb(dev);
+		if (result)
+			goto out_free;
 		break;
 	case EM28174_BOARD_HAUPPAUGE_WINTV_DUALHD_01595:
-		{
-			struct i2c_adapter *adapter;
-			struct i2c_client *client;
-			struct i2c_board_info info = {};
-			struct lgdt3306a_config lgdt3306a_config;
-			struct si2157_config si2157_config = {};
-
-			/* attach demod */
-			lgdt3306a_config = hauppauge_01595_lgdt3306a_config;
-			lgdt3306a_config.fe = &dvb->fe[0];
-			lgdt3306a_config.i2c_adapter = &adapter;
-			strlcpy(info.type, "lgdt3306a", sizeof(info.type));
-			info.addr = 0x59;
-			info.platform_data = &lgdt3306a_config;
-			request_module(info.type);
-			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus],
-					&info);
-			if (client == NULL || client->dev.driver == NULL) {
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_demod = client;
-
-			/* attach tuner */
-			si2157_config.fe = dvb->fe[0];
-			si2157_config.if_port = 1;
-			si2157_config.inversion = 1;
-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
-			si2157_config.mdev = dev->media_dev;
-#endif
-			memset(&info, 0, sizeof(struct i2c_board_info));
-			strlcpy(info.type, "si2157", sizeof(info.type));
-			info.addr = 0x60;
-			info.platform_data = &si2157_config;
-			request_module(info.type);
-
-			client = i2c_new_device(adapter, &info);
-			if (client == NULL || client->dev.driver == NULL) {
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-			if (!try_module_get(client->dev.driver->owner)) {
-				i2c_unregister_device(client);
-				module_put(dvb->i2c_client_demod->dev.driver->owner);
-				i2c_unregister_device(dvb->i2c_client_demod);
-				result = -ENODEV;
-				goto out_free;
-			}
-
-			dvb->i2c_client_tuner = client;
-		}
+		result = em28174_dvb_init_hauppauge_wintv_dualhd_01595(dev);
+		if (result)
+			goto out_free;
 		break;
 	default:
 		dev_err(&dev->intf->dev,
-- 
2.9.0

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] em28xx: split up em28xx_dvb_init to reduce stack size
  2017-12-11 12:05 [PATCH] em28xx: split up em28xx_dvb_init to reduce stack size Arnd Bergmann
@ 2017-12-14 17:10 ` Mauro Carvalho Chehab
  2017-12-15  9:34   ` Arnd Bergmann
  0 siblings, 1 reply; 3+ messages in thread
From: Mauro Carvalho Chehab @ 2017-12-14 17:10 UTC (permalink / raw)
  To: Arnd Bergmann; +Cc: Kevin Cheng, linux-media, linux-kernel, Antti Palosaari

Em Mon, 11 Dec 2017 13:05:02 +0100
Arnd Bergmann <arnd@arndb.de> escreveu:

> With CONFIG_KASAN, the init function uses a large amount of kernel stack:
> 
> drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init.part.4':
> drivers/media/usb/em28xx/em28xx-dvb.c:2061:1: error: the frame size of 3232 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
> 
> Using gcc-7 with -fsanitize-address-use-after-scope makes this even worse:
> 
> drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init':
> drivers/media/usb/em28xx/em28xx-dvb.c:2069:1: error: the frame size of 4280 bytes is larger than 3072 bytes [-Werror=frame-larger-than=]
> 
> By splitting out each part of the switch/case statement that has its own local
> variables into a separate function, no single one of them uses more than 500 bytes,
> and with a noinline_for_stack annotation we can ensure that they are not merged
> back together.

The right fix here is really to find a way to simplify the new method
of binding I2C devices by using some ancillary routines.

I'll keep this patch on my queue for now, but my plan is to try to solve
this issue instead of applying it, maybe on the next weeks (as the
volume of patches reduce due to end of year vacations and Seasons).

> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/media/usb/em28xx/em28xx-dvb.c | 947 ++++++++++++++++++----------------
>  1 file changed, 508 insertions(+), 439 deletions(-)
> 
> diff --git a/drivers/media/usb/em28xx/em28xx-dvb.c b/drivers/media/usb/em28xx/em28xx-dvb.c
> index 9950a740e04e..6665885dbaa7 100644
> --- a/drivers/media/usb/em28xx/em28xx-dvb.c
> +++ b/drivers/media/usb/em28xx/em28xx-dvb.c
> @@ -934,7 +934,7 @@ static struct lgdt3306a_config hauppauge_01595_lgdt3306a_config = {
>  
>  /* ------------------------------------------------------------------ */
>  
> -static int em28xx_attach_xc3028(u8 addr, struct em28xx *dev)
> +static noinline_for_stack int em28xx_attach_xc3028(u8 addr, struct em28xx *dev)
>  {
>  	struct dvb_frontend *fe;
>  	struct xc2028_config cfg;
> @@ -1126,6 +1126,492 @@ static void em28xx_unregister_dvb(struct em28xx_dvb *dvb)
>  	dvb_unregister_adapter(&dvb->adapter);
>  }
>  
> +static noinline_for_stack int em28174_dvb_init_pctv_460e(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_client *client;
> +	struct i2c_board_info board_info;
> +	struct tda10071_platform_data tda10071_pdata = {};
> +	struct a8293_platform_data a8293_pdata = {};
> +	int result;
> +
> +	/* attach demod + tuner combo */
> +	tda10071_pdata.clk = 40444000, /* 40.444 MHz */
> +	tda10071_pdata.i2c_wr_max = 64,
> +	tda10071_pdata.ts_mode = TDA10071_TS_SERIAL,
> +	tda10071_pdata.pll_multiplier = 20,
> +	tda10071_pdata.tuner_i2c_addr = 0x14,
> +	memset(&board_info, 0, sizeof(board_info));
> +	strlcpy(board_info.type, "tda10071_cx24118", I2C_NAME_SIZE);
> +	board_info.addr = 0x55;
> +	board_info.platform_data = &tda10071_pdata;
> +	request_module("tda10071");
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->fe[0] = tda10071_pdata.get_dvb_frontend(client);
> +	dvb->i2c_client_demod = client;
> +
> +	/* attach SEC */
> +	a8293_pdata.dvb_frontend = dvb->fe[0];
> +	memset(&board_info, 0, sizeof(board_info));
> +	strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
> +	board_info.addr = 0x08;
> +	board_info.platform_data = &a8293_pdata;
> +	request_module("a8293");
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->i2c_client_sec = client;
> +	result = 0;
> +out_free:
> +	return result;
> +}
> +
> +static noinline_for_stack int em28178_dvb_init_pctv_461e(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_client *client;
> +	struct i2c_adapter *i2c_adapter;
> +	struct i2c_board_info board_info;
> +	struct m88ds3103_platform_data m88ds3103_pdata = {};
> +	struct ts2020_config ts2020_config = {};
> +	struct a8293_platform_data a8293_pdata = {};
> +	int result;
> +
> +	/* attach demod */
> +	m88ds3103_pdata.clk = 27000000;
> +	m88ds3103_pdata.i2c_wr_max = 33;
> +	m88ds3103_pdata.ts_mode = M88DS3103_TS_PARALLEL;
> +	m88ds3103_pdata.ts_clk = 16000;
> +	m88ds3103_pdata.ts_clk_pol = 1;
> +	m88ds3103_pdata.agc = 0x99;
> +	memset(&board_info, 0, sizeof(board_info));
> +	strlcpy(board_info.type, "m88ds3103", I2C_NAME_SIZE);
> +	board_info.addr = 0x68;
> +	board_info.platform_data = &m88ds3103_pdata;
> +	request_module("m88ds3103");
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->fe[0] = m88ds3103_pdata.get_dvb_frontend(client);
> +	i2c_adapter = m88ds3103_pdata.get_i2c_adapter(client);
> +	dvb->i2c_client_demod = client;
> +
> +	/* attach tuner */
> +	ts2020_config.fe = dvb->fe[0];
> +	memset(&board_info, 0, sizeof(board_info));
> +	strlcpy(board_info.type, "ts2022", I2C_NAME_SIZE);
> +	board_info.addr = 0x60;
> +	board_info.platform_data = &ts2020_config;
> +	request_module("ts2020");
> +	client = i2c_new_device(i2c_adapter, &board_info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->i2c_client_tuner = client;
> +	/* delegate signal strength measurement to tuner */
> +	dvb->fe[0]->ops.read_signal_strength =
> +			dvb->fe[0]->ops.tuner_ops.get_rf_strength;
> +
> +	/* attach SEC */
> +	a8293_pdata.dvb_frontend = dvb->fe[0];
> +	memset(&board_info, 0, sizeof(board_info));
> +	strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
> +	board_info.addr = 0x08;
> +	board_info.platform_data = &a8293_pdata;
> +	request_module("a8293");
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_tuner->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_tuner);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_tuner->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_tuner);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->i2c_client_sec = client;
> +	result = 0;
> +out_free:
> +	return result;
> +}
> +
> +static noinline_for_stack int em28178_dvb_init_pctv_292e(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_adapter *adapter;
> +	struct i2c_client *client;
> +	struct i2c_board_info info;
> +	struct si2168_config si2168_config;
> +	struct si2157_config si2157_config;
> +	int result;
> +
> +	/* attach demod */
> +	memset(&si2168_config, 0, sizeof(si2168_config));
> +	si2168_config.i2c_adapter = &adapter;
> +	si2168_config.fe = &dvb->fe[0];
> +	si2168_config.ts_mode = SI2168_TS_PARALLEL;
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2168", I2C_NAME_SIZE);
> +	info.addr = 0x64;
> +	info.platform_data = &si2168_config;
> +	request_module(info.type);
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_demod = client;
> +
> +	/* attach tuner */
> +	memset(&si2157_config, 0, sizeof(si2157_config));
> +	si2157_config.fe = dvb->fe[0];
> +	si2157_config.if_port = 1;
> +#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> +	si2157_config.mdev = dev->media_dev;
> +#endif
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2157", I2C_NAME_SIZE);
> +	info.addr = 0x60;
> +	info.platform_data = &si2157_config;
> +	request_module(info.type);
> +	client = i2c_new_device(adapter, &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_tuner = client;
> +	dvb->fe[0]->ops.set_lna = em28xx_pctv_292e_set_lna;
> +	result = 0;
> +out_free:
> +	return result;
> +}
> +
> +static noinline_for_stack int em28178_dvb_init_terratec_t2_stick_hd(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_adapter *adapter;
> +	struct i2c_client *client;
> +	struct i2c_board_info info;
> +	struct si2168_config si2168_config;
> +	struct si2157_config si2157_config;
> +	int result;
> +
> +	/* attach demod */
> +	memset(&si2168_config, 0, sizeof(si2168_config));
> +	si2168_config.i2c_adapter = &adapter;
> +	si2168_config.fe = &dvb->fe[0];
> +	si2168_config.ts_mode = SI2168_TS_PARALLEL;
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2168", I2C_NAME_SIZE);
> +	info.addr = 0x64;
> +	info.platform_data = &si2168_config;
> +	request_module(info.type);
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_demod = client;
> +
> +	/* attach tuner */
> +	memset(&si2157_config, 0, sizeof(si2157_config));
> +	si2157_config.fe = dvb->fe[0];
> +	si2157_config.if_port = 0;
> +#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> +	si2157_config.mdev = dev->media_dev;
> +#endif
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2146", I2C_NAME_SIZE);
> +	info.addr = 0x60;
> +	info.platform_data = &si2157_config;
> +	request_module("si2157");
> +	client = i2c_new_device(adapter, &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_tuner = client;
> +	result = 0;
> +out_free:
> +	return result;
> +}
> +
> +static noinline_for_stack int em28178_dvb_init_plex_px_bcud(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_client *client;
> +	struct i2c_board_info info;
> +	struct tc90522_config tc90522_config;
> +	struct qm1d1c0042_config qm1d1c0042_config;
> +	int result;
> +
> +	/* attach demod */
> +	memset(&tc90522_config, 0, sizeof(tc90522_config));
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "tc90522sat", I2C_NAME_SIZE);
> +	info.addr = 0x15;
> +	info.platform_data = &tc90522_config;
> +	request_module("tc90522");
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->i2c_client_demod = client;
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	/* attach tuner */
> +	memset(&qm1d1c0042_config, 0,
> +	       sizeof(qm1d1c0042_config));
> +	qm1d1c0042_config.fe = tc90522_config.fe;
> +	qm1d1c0042_config.lpf = 1;
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "qm1d1c0042", I2C_NAME_SIZE);
> +	info.addr = 0x61;
> +	info.platform_data = &qm1d1c0042_config;
> +	request_module(info.type);
> +	client = i2c_new_device(tc90522_config.tuner_i2c,
> +				&info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->i2c_client_tuner = client;
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	dvb->fe[0] = tc90522_config.fe;
> +	px_bcud_init(dev);
> +	result = 0;
> +out_free:
> +	return result;
> +}
> +
> +static noinline_for_stack int em28174_dvb_init_hauppauge_wintv_dualhd_dvb(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_adapter *adapter;
> +	struct i2c_client *client;
> +	struct i2c_board_info info;
> +	struct si2168_config si2168_config;
> +	struct si2157_config si2157_config;
> +	int result;
> +
> +	/* attach demod */
> +	memset(&si2168_config, 0, sizeof(si2168_config));
> +	si2168_config.i2c_adapter = &adapter;
> +	si2168_config.fe = &dvb->fe[0];
> +	si2168_config.ts_mode = SI2168_TS_SERIAL;
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2168", I2C_NAME_SIZE);
> +	info.addr = 0x64;
> +	info.platform_data = &si2168_config;
> +	request_module(info.type);
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_demod = client;
> +
> +	/* attach tuner */
> +	memset(&si2157_config, 0, sizeof(si2157_config));
> +	si2157_config.fe = dvb->fe[0];
> +	si2157_config.if_port = 1;
> +#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> +	si2157_config.mdev = dev->media_dev;
> +#endif
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2157", I2C_NAME_SIZE);
> +	info.addr = 0x60;
> +	info.platform_data = &si2157_config;
> +	request_module(info.type);
> +	client = i2c_new_device(adapter, &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_tuner = client;
> +	result = 0;
> +out_free:
> +	return result;
> +}
> +
> +static int em28174_dvb_init_hauppauge_wintv_dualhd_01595(struct em28xx *dev)
> +{
> +	struct em28xx_dvb *dvb = dev->dvb;
> +	struct i2c_adapter *adapter;
> +	struct i2c_client *client;
> +	struct i2c_board_info info = {};
> +	struct lgdt3306a_config lgdt3306a_config;
> +	struct si2157_config si2157_config = {};
> +	int result;
> +
> +	/* attach demod */
> +	lgdt3306a_config = hauppauge_01595_lgdt3306a_config;
> +	lgdt3306a_config.fe = &dvb->fe[0];
> +	lgdt3306a_config.i2c_adapter = &adapter;
> +	strlcpy(info.type, "lgdt3306a", sizeof(info.type));
> +	info.addr = 0x59;
> +	info.platform_data = &lgdt3306a_config;
> +	request_module(info.type);
> +	client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus],
> +			&info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_demod = client;
> +
> +	/* attach tuner */
> +	si2157_config.fe = dvb->fe[0];
> +	si2157_config.if_port = 1;
> +	si2157_config.inversion = 1;
> +#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> +	si2157_config.mdev = dev->media_dev;
> +#endif
> +	memset(&info, 0, sizeof(struct i2c_board_info));
> +	strlcpy(info.type, "si2157", sizeof(info.type));
> +	info.addr = 0x60;
> +	info.platform_data = &si2157_config;
> +	request_module(info.type);
> +
> +	client = i2c_new_device(adapter, &info);
> +	if (client == NULL || client->dev.driver == NULL) {
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +	if (!try_module_get(client->dev.driver->owner)) {
> +		i2c_unregister_device(client);
> +		module_put(dvb->i2c_client_demod->dev.driver->owner);
> +		i2c_unregister_device(dvb->i2c_client_demod);
> +		result = -ENODEV;
> +		goto out_free;
> +	}
> +
> +	dvb->i2c_client_tuner = client;
> +	result = 0;
> +out_free:
> +	return result;
> +}
>  static int em28xx_dvb_init(struct em28xx *dev)
>  {
>  	int result = 0;
> @@ -1427,60 +1913,11 @@ static int em28xx_dvb_init(struct em28xx *dev)
>  				   &dev->i2c_adap[dev->def_i2c_bus],
>  				   &c3tech_duo_tda18271_config);
>  		break;
> -	case EM28174_BOARD_PCTV_460E: {
> -		struct i2c_client *client;
> -		struct i2c_board_info board_info;
> -		struct tda10071_platform_data tda10071_pdata = {};
> -		struct a8293_platform_data a8293_pdata = {};
> -
> -		/* attach demod + tuner combo */
> -		tda10071_pdata.clk = 40444000, /* 40.444 MHz */
> -		tda10071_pdata.i2c_wr_max = 64,
> -		tda10071_pdata.ts_mode = TDA10071_TS_SERIAL,
> -		tda10071_pdata.pll_multiplier = 20,
> -		tda10071_pdata.tuner_i2c_addr = 0x14,
> -		memset(&board_info, 0, sizeof(board_info));
> -		strlcpy(board_info.type, "tda10071_cx24118", I2C_NAME_SIZE);
> -		board_info.addr = 0x55;
> -		board_info.platform_data = &tda10071_pdata;
> -		request_module("tda10071");
> -		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> -		if (client == NULL || client->dev.driver == NULL) {
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		if (!try_module_get(client->dev.driver->owner)) {
> -			i2c_unregister_device(client);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		dvb->fe[0] = tda10071_pdata.get_dvb_frontend(client);
> -		dvb->i2c_client_demod = client;
> -
> -		/* attach SEC */
> -		a8293_pdata.dvb_frontend = dvb->fe[0];
> -		memset(&board_info, 0, sizeof(board_info));
> -		strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
> -		board_info.addr = 0x08;
> -		board_info.platform_data = &a8293_pdata;
> -		request_module("a8293");
> -		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> -		if (client == NULL || client->dev.driver == NULL) {
> -			module_put(dvb->i2c_client_demod->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_demod);
> -			result = -ENODEV;
> +	case EM28174_BOARD_PCTV_460E:
> +		result = em28174_dvb_init_pctv_460e(dev);
> +		if (result)
>  			goto out_free;
> -		}
> -		if (!try_module_get(client->dev.driver->owner)) {
> -			i2c_unregister_device(client);
> -			module_put(dvb->i2c_client_demod->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_demod);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		dvb->i2c_client_sec = client;
>  		break;
> -	}
>  	case EM2874_BOARD_DELOCK_61959:
>  	case EM2874_BOARD_MAXMEDIA_UB425_TC:
>  		/* attach demodulator */
> @@ -1627,403 +2064,35 @@ static int em28xx_dvb_init(struct em28xx *dev)
>  			}
>  		}
>  		break;
> -	case EM28178_BOARD_PCTV_461E: {
> -		struct i2c_client *client;
> -		struct i2c_adapter *i2c_adapter;
> -		struct i2c_board_info board_info;
> -		struct m88ds3103_platform_data m88ds3103_pdata = {};
> -		struct ts2020_config ts2020_config = {};
> -		struct a8293_platform_data a8293_pdata = {};
> -
> -		/* attach demod */
> -		m88ds3103_pdata.clk = 27000000;
> -		m88ds3103_pdata.i2c_wr_max = 33;
> -		m88ds3103_pdata.ts_mode = M88DS3103_TS_PARALLEL;
> -		m88ds3103_pdata.ts_clk = 16000;
> -		m88ds3103_pdata.ts_clk_pol = 1;
> -		m88ds3103_pdata.agc = 0x99;
> -		memset(&board_info, 0, sizeof(board_info));
> -		strlcpy(board_info.type, "m88ds3103", I2C_NAME_SIZE);
> -		board_info.addr = 0x68;
> -		board_info.platform_data = &m88ds3103_pdata;
> -		request_module("m88ds3103");
> -		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> -		if (client == NULL || client->dev.driver == NULL) {
> -			result = -ENODEV;
> +	case EM28178_BOARD_PCTV_461E: 
> +		result = em28178_dvb_init_pctv_461e(dev);
> +		if (result)
>  			goto out_free;
> -		}
> -		if (!try_module_get(client->dev.driver->owner)) {
> -			i2c_unregister_device(client);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		dvb->fe[0] = m88ds3103_pdata.get_dvb_frontend(client);
> -		i2c_adapter = m88ds3103_pdata.get_i2c_adapter(client);
> -		dvb->i2c_client_demod = client;
> -
> -		/* attach tuner */
> -		ts2020_config.fe = dvb->fe[0];
> -		memset(&board_info, 0, sizeof(board_info));
> -		strlcpy(board_info.type, "ts2022", I2C_NAME_SIZE);
> -		board_info.addr = 0x60;
> -		board_info.platform_data = &ts2020_config;
> -		request_module("ts2020");
> -		client = i2c_new_device(i2c_adapter, &board_info);
> -		if (client == NULL || client->dev.driver == NULL) {
> -			module_put(dvb->i2c_client_demod->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_demod);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		if (!try_module_get(client->dev.driver->owner)) {
> -			i2c_unregister_device(client);
> -			module_put(dvb->i2c_client_demod->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_demod);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		dvb->i2c_client_tuner = client;
> -		/* delegate signal strength measurement to tuner */
> -		dvb->fe[0]->ops.read_signal_strength =
> -				dvb->fe[0]->ops.tuner_ops.get_rf_strength;
> -
> -		/* attach SEC */
> -		a8293_pdata.dvb_frontend = dvb->fe[0];
> -		memset(&board_info, 0, sizeof(board_info));
> -		strlcpy(board_info.type, "a8293", I2C_NAME_SIZE);
> -		board_info.addr = 0x08;
> -		board_info.platform_data = &a8293_pdata;
> -		request_module("a8293");
> -		client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &board_info);
> -		if (client == NULL || client->dev.driver == NULL) {
> -			module_put(dvb->i2c_client_tuner->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_tuner);
> -			module_put(dvb->i2c_client_demod->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_demod);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		if (!try_module_get(client->dev.driver->owner)) {
> -			i2c_unregister_device(client);
> -			module_put(dvb->i2c_client_tuner->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_tuner);
> -			module_put(dvb->i2c_client_demod->dev.driver->owner);
> -			i2c_unregister_device(dvb->i2c_client_demod);
> -			result = -ENODEV;
> -			goto out_free;
> -		}
> -		dvb->i2c_client_sec = client;
>  		break;
> -	}
>  	case EM28178_BOARD_PCTV_292E:
> -		{
> -			struct i2c_adapter *adapter;
> -			struct i2c_client *client;
> -			struct i2c_board_info info;
> -			struct si2168_config si2168_config;
> -			struct si2157_config si2157_config;
> -
> -			/* attach demod */
> -			memset(&si2168_config, 0, sizeof(si2168_config));
> -			si2168_config.i2c_adapter = &adapter;
> -			si2168_config.fe = &dvb->fe[0];
> -			si2168_config.ts_mode = SI2168_TS_PARALLEL;
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2168", I2C_NAME_SIZE);
> -			info.addr = 0x64;
> -			info.platform_data = &si2168_config;
> -			request_module(info.type);
> -			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_demod = client;
> -
> -			/* attach tuner */
> -			memset(&si2157_config, 0, sizeof(si2157_config));
> -			si2157_config.fe = dvb->fe[0];
> -			si2157_config.if_port = 1;
> -#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> -			si2157_config.mdev = dev->media_dev;
> -#endif
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2157", I2C_NAME_SIZE);
> -			info.addr = 0x60;
> -			info.platform_data = &si2157_config;
> -			request_module(info.type);
> -			client = i2c_new_device(adapter, &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_tuner = client;
> -			dvb->fe[0]->ops.set_lna = em28xx_pctv_292e_set_lna;
> -		}
> +		result = em28178_dvb_init_pctv_292e(dev);
> +		if (result)
> +			goto out_free;
>  		break;
>  	case EM28178_BOARD_TERRATEC_T2_STICK_HD:
> -		{
> -			struct i2c_adapter *adapter;
> -			struct i2c_client *client;
> -			struct i2c_board_info info;
> -			struct si2168_config si2168_config;
> -			struct si2157_config si2157_config;
> -
> -			/* attach demod */
> -			memset(&si2168_config, 0, sizeof(si2168_config));
> -			si2168_config.i2c_adapter = &adapter;
> -			si2168_config.fe = &dvb->fe[0];
> -			si2168_config.ts_mode = SI2168_TS_PARALLEL;
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2168", I2C_NAME_SIZE);
> -			info.addr = 0x64;
> -			info.platform_data = &si2168_config;
> -			request_module(info.type);
> -			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_demod = client;
> -
> -			/* attach tuner */
> -			memset(&si2157_config, 0, sizeof(si2157_config));
> -			si2157_config.fe = dvb->fe[0];
> -			si2157_config.if_port = 0;
> -#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> -			si2157_config.mdev = dev->media_dev;
> -#endif
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2146", I2C_NAME_SIZE);
> -			info.addr = 0x60;
> -			info.platform_data = &si2157_config;
> -			request_module("si2157");
> -			client = i2c_new_device(adapter, &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_tuner = client;
> -		}
> +		result = em28178_dvb_init_terratec_t2_stick_hd(dev);
> +		if (result)
> +			goto out_free;
>  		break;
> -
>  	case EM28178_BOARD_PLEX_PX_BCUD:
> -		{
> -			struct i2c_client *client;
> -			struct i2c_board_info info;
> -			struct tc90522_config tc90522_config;
> -			struct qm1d1c0042_config qm1d1c0042_config;
> -
> -			/* attach demod */
> -			memset(&tc90522_config, 0, sizeof(tc90522_config));
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "tc90522sat", I2C_NAME_SIZE);
> -			info.addr = 0x15;
> -			info.platform_data = &tc90522_config;
> -			request_module("tc90522");
> -			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -			dvb->i2c_client_demod = client;
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			/* attach tuner */
> -			memset(&qm1d1c0042_config, 0,
> -			       sizeof(qm1d1c0042_config));
> -			qm1d1c0042_config.fe = tc90522_config.fe;
> -			qm1d1c0042_config.lpf = 1;
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "qm1d1c0042", I2C_NAME_SIZE);
> -			info.addr = 0x61;
> -			info.platform_data = &qm1d1c0042_config;
> -			request_module(info.type);
> -			client = i2c_new_device(tc90522_config.tuner_i2c,
> -						&info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -			dvb->i2c_client_tuner = client;
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -			dvb->fe[0] = tc90522_config.fe;
> -			px_bcud_init(dev);
> -		}
> +		result = em28178_dvb_init_plex_px_bcud(dev);
> +		if (result)
> +			goto out_free;
>  		break;
>  	case EM28174_BOARD_HAUPPAUGE_WINTV_DUALHD_DVB:
> -		{
> -			struct i2c_adapter *adapter;
> -			struct i2c_client *client;
> -			struct i2c_board_info info;
> -			struct si2168_config si2168_config;
> -			struct si2157_config si2157_config;
> -
> -			/* attach demod */
> -			memset(&si2168_config, 0, sizeof(si2168_config));
> -			si2168_config.i2c_adapter = &adapter;
> -			si2168_config.fe = &dvb->fe[0];
> -			si2168_config.ts_mode = SI2168_TS_SERIAL;
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2168", I2C_NAME_SIZE);
> -			info.addr = 0x64;
> -			info.platform_data = &si2168_config;
> -			request_module(info.type);
> -			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus], &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_demod = client;
> -
> -			/* attach tuner */
> -			memset(&si2157_config, 0, sizeof(si2157_config));
> -			si2157_config.fe = dvb->fe[0];
> -			si2157_config.if_port = 1;
> -#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> -			si2157_config.mdev = dev->media_dev;
> -#endif
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2157", I2C_NAME_SIZE);
> -			info.addr = 0x60;
> -			info.platform_data = &si2157_config;
> -			request_module(info.type);
> -			client = i2c_new_device(adapter, &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_tuner = client;
> -
> -		}
> +		result = em28174_dvb_init_hauppauge_wintv_dualhd_dvb(dev);
> +		if (result)
> +			goto out_free;
>  		break;
>  	case EM28174_BOARD_HAUPPAUGE_WINTV_DUALHD_01595:
> -		{
> -			struct i2c_adapter *adapter;
> -			struct i2c_client *client;
> -			struct i2c_board_info info = {};
> -			struct lgdt3306a_config lgdt3306a_config;
> -			struct si2157_config si2157_config = {};
> -
> -			/* attach demod */
> -			lgdt3306a_config = hauppauge_01595_lgdt3306a_config;
> -			lgdt3306a_config.fe = &dvb->fe[0];
> -			lgdt3306a_config.i2c_adapter = &adapter;
> -			strlcpy(info.type, "lgdt3306a", sizeof(info.type));
> -			info.addr = 0x59;
> -			info.platform_data = &lgdt3306a_config;
> -			request_module(info.type);
> -			client = i2c_new_device(&dev->i2c_adap[dev->def_i2c_bus],
> -					&info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_demod = client;
> -
> -			/* attach tuner */
> -			si2157_config.fe = dvb->fe[0];
> -			si2157_config.if_port = 1;
> -			si2157_config.inversion = 1;
> -#ifdef CONFIG_MEDIA_CONTROLLER_DVB
> -			si2157_config.mdev = dev->media_dev;
> -#endif
> -			memset(&info, 0, sizeof(struct i2c_board_info));
> -			strlcpy(info.type, "si2157", sizeof(info.type));
> -			info.addr = 0x60;
> -			info.platform_data = &si2157_config;
> -			request_module(info.type);
> -
> -			client = i2c_new_device(adapter, &info);
> -			if (client == NULL || client->dev.driver == NULL) {
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -			if (!try_module_get(client->dev.driver->owner)) {
> -				i2c_unregister_device(client);
> -				module_put(dvb->i2c_client_demod->dev.driver->owner);
> -				i2c_unregister_device(dvb->i2c_client_demod);
> -				result = -ENODEV;
> -				goto out_free;
> -			}
> -
> -			dvb->i2c_client_tuner = client;
> -		}
> +		result = em28174_dvb_init_hauppauge_wintv_dualhd_01595(dev);
> +		if (result)
> +			goto out_free;
>  		break;
>  	default:
>  		dev_err(&dev->intf->dev,



Thanks,
Mauro

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] em28xx: split up em28xx_dvb_init to reduce stack size
  2017-12-14 17:10 ` Mauro Carvalho Chehab
@ 2017-12-15  9:34   ` Arnd Bergmann
  0 siblings, 0 replies; 3+ messages in thread
From: Arnd Bergmann @ 2017-12-15  9:34 UTC (permalink / raw)
  To: Mauro Carvalho Chehab
  Cc: Kevin Cheng, Linux Media Mailing List, Linux Kernel Mailing List,
	Antti Palosaari, Andrew Morton

On Thu, Dec 14, 2017 at 6:10 PM, Mauro Carvalho Chehab
<mchehab@kernel.org> wrote:
> Em Mon, 11 Dec 2017 13:05:02 +0100
> Arnd Bergmann <arnd@arndb.de> escreveu:
>
>> With CONFIG_KASAN, the init function uses a large amount of kernel stack:
>>
>> drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init.part.4':
>> drivers/media/usb/em28xx/em28xx-dvb.c:2061:1: error: the frame size of 3232 bytes is larger than 2048 bytes [-Werror=frame-larger-than=]
>>
>> Using gcc-7 with -fsanitize-address-use-after-scope makes this even worse:
>>
>> drivers/media/usb/em28xx/em28xx-dvb.c: In function 'em28xx_dvb_init':
>> drivers/media/usb/em28xx/em28xx-dvb.c:2069:1: error: the frame size of 4280 bytes is larger than 3072 bytes [-Werror=frame-larger-than=]
>>
>> By splitting out each part of the switch/case statement that has its own local
>> variables into a separate function, no single one of them uses more than 500 bytes,
>> and with a noinline_for_stack annotation we can ensure that they are not merged
>> back together.
>
> The right fix here is really to find a way to simplify the new method
> of binding I2C devices by using some ancillary routines.
>
> I'll keep this patch on my queue for now, but my plan is to try to solve
> this issue instead of applying it, maybe on the next weeks (as the
> volume of patches reduce due to end of year vacations and Seasons).

That's ok, thanks. We have a workaround in linux-mm that partially solves this
problem to the point where the stack size goes down to 1600 bytes with KASAN,
that by itself would be sufficient to let us enable CONFIG_FRAME_WARN
again for 64-bit platforms with the default 2048 byte warning limit. I reposted
that patch mostly since I want to lower the frame sizes further so we can
reduce the warning limit to 1280 bytes for 64-bit architectures in the future.
There around 10 patches needed for that, and they mostly seem to address
actual issues, so I'd like them to get addressed eventually and set the limit
low enough that the warnings we get on 64-bit are more useful again.

However, could you please revisit two other patches:

https://patchwork.linuxtv.org/patch/45716/ dvb-frontends: fix i2c
access helpers for KASAN
https://patchwork.linuxtv.org/patch/45709/ r820t: fix r820t_write_reg for KASAN

These are currently the ones I'm most interested in getting merged
into v4.15 and LTS kernels for the stack size reduction, since they
are blocking the patch that enables CONFIG_FRAME_WARN for
allmodconfig.

Thanks,

       Arnd

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2017-12-15  9:34 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-12-11 12:05 [PATCH] em28xx: split up em28xx_dvb_init to reduce stack size Arnd Bergmann
2017-12-14 17:10 ` Mauro Carvalho Chehab
2017-12-15  9:34   ` Arnd Bergmann

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