[PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Andrey Smirnov]

Platform device core assumes the ownership of dev.platform_data as
well as that it is dynamically allocated and it will try to kfree it
as a part of platform_device_release(). Change the code to use
platform_device_add_data() n instead of a pointer to a static memory
to avoid causing a BUG() when calling platform_device_put().

The problem can be reproduced by artificially enabling the error path
of platform_device_add() call (around line 357).

Note that this change also allows us to constify imx7_pgc_domains,
since we no longer need to be able to modify it.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---

Changes since [v2]:

    - Patch reworked to use platform_device_add_data() as per request from Shawn

Changes since [v1]:

    - Replaced devm_kzalloc() with devm_kmalloc() as per suggestion from Stefan

[v1] lkml.kernel.org/r/20180110161608.13015-1-andrew.smirnov@gmail.com
[v2] lkml.kernel.org/r/20180122150748.1742-1-andrew.smirnov@gmail.com

 drivers/soc/imx/gpcv2.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
index afc7ecc3c187..f4e3bd40c72e 100644
--- a/drivers/soc/imx/gpcv2.c
+++ b/drivers/soc/imx/gpcv2.c
@@ -155,7 +155,7 @@ static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
 	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
 }
 
-static struct imx7_pgc_domain imx7_pgc_domains[] = {
+static const struct imx7_pgc_domain imx7_pgc_domains[] = {
 	[IMX7_POWER_DOMAIN_MIPI_PHY] = {
 		.genpd = {
 			.name      = "mipi-phy",
@@ -321,11 +321,6 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
 			continue;
 		}
 
-		domain = &imx7_pgc_domains[domain_index];
-		domain->regmap = regmap;
-		domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
-		domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
-
 		pd_pdev = platform_device_alloc("imx7-pgc-domain",
 						domain_index);
 		if (!pd_pdev) {
@@ -334,7 +329,20 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
 			return -ENOMEM;
 		}
 
-		pd_pdev->dev.platform_data = domain;
+		ret = platform_device_add_data(pd_pdev,
+					       &imx7_pgc_domains[domain_index],
+					       sizeof(imx7_pgc_domains[domain_index]));
+		if (ret) {
+			platform_device_put(pd_pdev);
+			of_node_put(np);
+			return ret;
+		}
+
+		domain = pd_pdev->dev.platform_data;
+		domain->regmap = regmap;
+		domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
+		domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
+
 		pd_pdev->dev.parent = dev;
 		pd_pdev->dev.of_node = np;
 
-- 
2.14.3

[PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Andrey Smirnov]

Platform device core assumes the ownership of dev.platform_data as
well as that it is dynamically allocated and it will try to kfree it
as a part of platform_device_release(). Change the code to use
platform_device_add_data() n instead of a pointer to a static memory
to avoid causing a BUG() when calling platform_device_put().

The problem can be reproduced by artificially enabling the error path
of platform_device_add() call (around line 357).

Note that this change also allows us to constify imx7_pgc_domains,
since we no longer need to be able to modify it.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---

Changes since [v2]:

    - Patch reworked to use platform_device_add_data() as per request from Shawn

Changes since [v1]:

    - Replaced devm_kzalloc() with devm_kmalloc() as per suggestion from Stefan

[v1] lkml.kernel.org/r/20180110161608.13015-1-andrew.smirnov at gmail.com
[v2] lkml.kernel.org/r/20180122150748.1742-1-andrew.smirnov at gmail.com

 drivers/soc/imx/gpcv2.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/soc/imx/gpcv2.c b/drivers/soc/imx/gpcv2.c
index afc7ecc3c187..f4e3bd40c72e 100644
--- a/drivers/soc/imx/gpcv2.c
+++ b/drivers/soc/imx/gpcv2.c
@@ -155,7 +155,7 @@ static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
 	return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
 }
 
-static struct imx7_pgc_domain imx7_pgc_domains[] = {
+static const struct imx7_pgc_domain imx7_pgc_domains[] = {
 	[IMX7_POWER_DOMAIN_MIPI_PHY] = {
 		.genpd = {
 			.name      = "mipi-phy",
@@ -321,11 +321,6 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
 			continue;
 		}
 
-		domain = &imx7_pgc_domains[domain_index];
-		domain->regmap = regmap;
-		domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
-		domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
-
 		pd_pdev = platform_device_alloc("imx7-pgc-domain",
 						domain_index);
 		if (!pd_pdev) {
@@ -334,7 +329,20 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
 			return -ENOMEM;
 		}
 
-		pd_pdev->dev.platform_data = domain;
+		ret = platform_device_add_data(pd_pdev,
+					       &imx7_pgc_domains[domain_index],
+					       sizeof(imx7_pgc_domains[domain_index]));
+		if (ret) {
+			platform_device_put(pd_pdev);
+			of_node_put(np);
+			return ret;
+		}
+
+		domain = pd_pdev->dev.platform_data;
+		domain->regmap = regmap;
+		domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
+		domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
+
 		pd_pdev->dev.parent = dev;
 		pd_pdev->dev.of_node = np;
 
-- 
2.14.3

[PATCH v3 2/2] soc: imx: gpc: Do not pass static memory as platform data

[Andrey Smirnov]

Platform device core assumes the ownership of dev.platform_data as
well as that it is dynamically allocated and it will try to kfree it
as a part of platform_device_release(). Change the code to use
platform_device_add_data() instead of a pointer to a static memory to
avoid causing a BUG() when calling platform_device_put().

The problem can be reproduced by artificially enabling the error path
of platform_device_add() call (around line 452).

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---

Changes since [v2]:

    - Patch reworked to use platform_device_add_data() as per request from Shawn

Changes since [v1]:

    - Replaced devm_kzalloc() with devm_kmalloc() as per suggestion from Stefan

[v1] lkml.kernel.org/r/20180110161608.13015-2-andrew.smirnov@gmail.com
[v2] lkml.kernel.org/r/20180122150748.1742-2-andrew.smirnov@gmail.com

 drivers/soc/imx/gpc.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/soc/imx/gpc.c b/drivers/soc/imx/gpc.c
index c4d35f32af8d..32f0748fd067 100644
--- a/drivers/soc/imx/gpc.c
+++ b/drivers/soc/imx/gpc.c
@@ -443,17 +443,25 @@ static int imx_gpc_probe(struct platform_device *pdev)
 			if (domain_index >= of_id_data->num_domains)
 				continue;
 
-			domain = &imx_gpc_domains[domain_index];
-			domain->regmap = regmap;
-			domain->ipg_rate_mhz = ipg_rate_mhz;
-
 			pd_pdev = platform_device_alloc("imx-pgc-power-domain",
 							domain_index);
 			if (!pd_pdev) {
 				of_node_put(np);
 				return -ENOMEM;
 			}
-			pd_pdev->dev.platform_data = domain;
+
+			ret = platform_device_add_data(pd_pdev,
+						       &imx_gpc_domains[domain_index],
+						       sizeof(imx_gpc_domains[domain_index]));
+			if (ret) {
+				platform_device_put(pd_pdev);
+				of_node_put(np);
+				return ret;
+			}
+			domain = pd_pdev->dev.platform_data;
+			domain->regmap = regmap;
+			domain->ipg_rate_mhz = ipg_rate_mhz;
+
 			pd_pdev->dev.parent = &pdev->dev;
 			pd_pdev->dev.of_node = np;
 
-- 
2.14.3

[PATCH v3 2/2] soc: imx: gpc: Do not pass static memory as platform data

[Andrey Smirnov]

Platform device core assumes the ownership of dev.platform_data as
well as that it is dynamically allocated and it will try to kfree it
as a part of platform_device_release(). Change the code to use
platform_device_add_data() instead of a pointer to a static memory to
avoid causing a BUG() when calling platform_device_put().

The problem can be reproduced by artificially enabling the error path
of platform_device_add() call (around line 452).

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
---

Changes since [v2]:

    - Patch reworked to use platform_device_add_data() as per request from Shawn

Changes since [v1]:

    - Replaced devm_kzalloc() with devm_kmalloc() as per suggestion from Stefan

[v1] lkml.kernel.org/r/20180110161608.13015-2-andrew.smirnov at gmail.com
[v2] lkml.kernel.org/r/20180122150748.1742-2-andrew.smirnov at gmail.com

 drivers/soc/imx/gpc.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/soc/imx/gpc.c b/drivers/soc/imx/gpc.c
index c4d35f32af8d..32f0748fd067 100644
--- a/drivers/soc/imx/gpc.c
+++ b/drivers/soc/imx/gpc.c
@@ -443,17 +443,25 @@ static int imx_gpc_probe(struct platform_device *pdev)
 			if (domain_index >= of_id_data->num_domains)
 				continue;
 
-			domain = &imx_gpc_domains[domain_index];
-			domain->regmap = regmap;
-			domain->ipg_rate_mhz = ipg_rate_mhz;
-
 			pd_pdev = platform_device_alloc("imx-pgc-power-domain",
 							domain_index);
 			if (!pd_pdev) {
 				of_node_put(np);
 				return -ENOMEM;
 			}
-			pd_pdev->dev.platform_data = domain;
+
+			ret = platform_device_add_data(pd_pdev,
+						       &imx_gpc_domains[domain_index],
+						       sizeof(imx_gpc_domains[domain_index]));
+			if (ret) {
+				platform_device_put(pd_pdev);
+				of_node_put(np);
+				return ret;
+			}
+			domain = pd_pdev->dev.platform_data;
+			domain->regmap = regmap;
+			domain->ipg_rate_mhz = ipg_rate_mhz;
+
 			pd_pdev->dev.parent = &pdev->dev;
 			pd_pdev->dev.of_node = np;
 
-- 
2.14.3

Re: [PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Andrey Smirnov]

On Tue, Apr 10, 2018 at 11:32 AM, Andrey Smirnov
<andrew.smirnov@gmail.com> wrote:
> Platform device core assumes the ownership of dev.platform_data as
> well as that it is dynamically allocated and it will try to kfree it
> as a part of platform_device_release(). Change the code to use
> platform_device_add_data() n instead of a pointer to a static memory
> to avoid causing a BUG() when calling platform_device_put().
>
> The problem can be reproduced by artificially enabling the error path
> of platform_device_add() call (around line 357).
>
> Note that this change also allows us to constify imx7_pgc_domains,
> since we no longer need to be able to modify it.
>

Shawn,

What's the status of these two patches? Do I need to change anything
or are they good to go?

Thanks,
Andrey Smirnov

[PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Andrey Smirnov]

On Tue, Apr 10, 2018 at 11:32 AM, Andrey Smirnov
<andrew.smirnov@gmail.com> wrote:
> Platform device core assumes the ownership of dev.platform_data as
> well as that it is dynamically allocated and it will try to kfree it
> as a part of platform_device_release(). Change the code to use
> platform_device_add_data() n instead of a pointer to a static memory
> to avoid causing a BUG() when calling platform_device_put().
>
> The problem can be reproduced by artificially enabling the error path
> of platform_device_add() call (around line 357).
>
> Note that this change also allows us to constify imx7_pgc_domains,
> since we no longer need to be able to modify it.
>

Shawn,

What's the status of these two patches? Do I need to change anything
or are they good to go?

Thanks,
Andrey Smirnov

Re: [PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Shawn Guo]

On Sat, May 19, 2018 at 03:35:55PM -0700, Andrey Smirnov wrote:
> On Tue, Apr 10, 2018 at 11:32 AM, Andrey Smirnov
> <andrew.smirnov@gmail.com> wrote:
> > Platform device core assumes the ownership of dev.platform_data as
> > well as that it is dynamically allocated and it will try to kfree it
> > as a part of platform_device_release(). Change the code to use
> > platform_device_add_data() n instead of a pointer to a static memory
> > to avoid causing a BUG() when calling platform_device_put().
> >
> > The problem can be reproduced by artificially enabling the error path
> > of platform_device_add() call (around line 357).
> >
> > Note that this change also allows us to constify imx7_pgc_domains,
> > since we no longer need to be able to modify it.
> >
> 
> Shawn,
> 
> What's the status of these two patches? Do I need to change anything
> or are they good to go?

The patches were queued on imx/drivers branch for a while.  I forgot to
let you know.  Sorry.

Shawn

[PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Shawn Guo]

On Sat, May 19, 2018 at 03:35:55PM -0700, Andrey Smirnov wrote:
> On Tue, Apr 10, 2018 at 11:32 AM, Andrey Smirnov
> <andrew.smirnov@gmail.com> wrote:
> > Platform device core assumes the ownership of dev.platform_data as
> > well as that it is dynamically allocated and it will try to kfree it
> > as a part of platform_device_release(). Change the code to use
> > platform_device_add_data() n instead of a pointer to a static memory
> > to avoid causing a BUG() when calling platform_device_put().
> >
> > The problem can be reproduced by artificially enabling the error path
> > of platform_device_add() call (around line 357).
> >
> > Note that this change also allows us to constify imx7_pgc_domains,
> > since we no longer need to be able to modify it.
> >
> 
> Shawn,
> 
> What's the status of these two patches? Do I need to change anything
> or are they good to go?

The patches were queued on imx/drivers branch for a while.  I forgot to
let you know.  Sorry.

Shawn

Re: [PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Andrey Smirnov]

On Sat, May 19, 2018 at 11:26 PM, Shawn Guo <shawnguo@kernel.org> wrote:
> On Sat, May 19, 2018 at 03:35:55PM -0700, Andrey Smirnov wrote:
>> On Tue, Apr 10, 2018 at 11:32 AM, Andrey Smirnov
>> <andrew.smirnov@gmail.com> wrote:
>> > Platform device core assumes the ownership of dev.platform_data as
>> > well as that it is dynamically allocated and it will try to kfree it
>> > as a part of platform_device_release(). Change the code to use
>> > platform_device_add_data() n instead of a pointer to a static memory
>> > to avoid causing a BUG() when calling platform_device_put().
>> >
>> > The problem can be reproduced by artificially enabling the error path
>> > of platform_device_add() call (around line 357).
>> >
>> > Note that this change also allows us to constify imx7_pgc_domains,
>> > since we no longer need to be able to modify it.
>> >
>>
>> Shawn,
>>
>> What's the status of these two patches? Do I need to change anything
>> or are they good to go?
>
> The patches were queued on imx/drivers branch for a while.  I forgot to
> let you know.  Sorry.
>

No worries and good to know!

Thanks,
Andrey Smirnov

[PATCH v3 1/2] soc: imx: gpcv2: Do not pass static memory as platform data

[Andrey Smirnov]

On Sat, May 19, 2018 at 11:26 PM, Shawn Guo <shawnguo@kernel.org> wrote:
> On Sat, May 19, 2018 at 03:35:55PM -0700, Andrey Smirnov wrote:
>> On Tue, Apr 10, 2018 at 11:32 AM, Andrey Smirnov
>> <andrew.smirnov@gmail.com> wrote:
>> > Platform device core assumes the ownership of dev.platform_data as
>> > well as that it is dynamically allocated and it will try to kfree it
>> > as a part of platform_device_release(). Change the code to use
>> > platform_device_add_data() n instead of a pointer to a static memory
>> > to avoid causing a BUG() when calling platform_device_put().
>> >
>> > The problem can be reproduced by artificially enabling the error path
>> > of platform_device_add() call (around line 357).
>> >
>> > Note that this change also allows us to constify imx7_pgc_domains,
>> > since we no longer need to be able to modify it.
>> >
>>
>> Shawn,
>>
>> What's the status of these two patches? Do I need to change anything
>> or are they good to go?
>
> The patches were queued on imx/drivers branch for a while.  I forgot to
> let you know.  Sorry.
>

No worries and good to know!

Thanks,
Andrey Smirnov