clk: imx8m: Suppress bind attrs

Commit Message

Leonard Crestez Nov. 21, 2019, 1:52 p.m. UTC

The clock drivers on imx8m series are registered as platform devices and
this opens the possibility of reloading the driver at runtime.

This doesn't actually work: clocks are never removed and attempting to
bind again results in registration errors and a crash. Almost all
devices depend on clocks anyway so rebinding is unlikely to ever be
useful

Fix this by explicitly suppressing bind attrs like several other
clock drivers.

Signed-off-by: Leonard Crestez <[e-mail]>
Reviewed-by: Peng Fan <[e-mail]>

---
No cc: stable because because there are likely many other opportunities
to crash the system by echoing random stuff in sysfs as root.

Changes since v1:
* Add source comments as well
Link to v1: https://patchwork.kernel.org/patch/11250389/

 drivers/clk/imx/clk-imx8mm.c | 5 +++++
 drivers/clk/imx/clk-imx8mn.c | 5 +++++
 drivers/clk/imx/clk-imx8mq.c | 5 +++++
 3 files changed, 15 insertions(+)

Comments

Shawn Guo Dec. 9, 2019, 2:36 a.m. UTC | #1

On Thu, Nov 21, 2019 at 03:52:17PM +0200, Leonard Crestez wrote:
> The clock drivers on imx8m series are registered as platform devices and
> this opens the possibility of reloading the driver at runtime.
> 
> This doesn't actually work: clocks are never removed and attempting to
> bind again results in registration errors and a crash. Almost all
> devices depend on clocks anyway so rebinding is unlikely to ever be
> useful
> 
> Fix this by explicitly suppressing bind attrs like several other
> clock drivers.
> 
> Signed-off-by: Leonard Crestez <[e-mail]>
> Reviewed-by: Peng Fan <[e-mail]>

Applied, thanks.

Patch

diff --git a/drivers/clk/imx/clk-imx8mm.c b/drivers/clk/imx/clk-imx8mm.c
index 030b15d7c0ce..ed3ce492151c 100644
--- a/drivers/clk/imx/clk-imx8mm.c
+++ b/drivers/clk/imx/clk-imx8mm.c
@@ -614,9 +614,14 @@  MODULE_DEVICE_TABLE(of, imx8mm_clk_of_match);
 
 static struct platform_driver imx8mm_clk_driver = {
 	.probe = imx8mm_clocks_probe,
 	.driver = {
 		.name = "imx8mm-ccm",
+		/*
+		 * Disable bind attributes: clocks are not removed and
+		 * reloading the driver will crash or break devices.
+		 */
+		.suppress_bind_attrs = true,
 		.of_match_table = of_match_ptr(imx8mm_clk_of_match),
 	},
 };
 module_platform_driver(imx8mm_clk_driver);
diff --git a/drivers/clk/imx/clk-imx8mn.c b/drivers/clk/imx/clk-imx8mn.c
index 9f5a5a56b45e..d95e282ff1fb 100644
--- a/drivers/clk/imx/clk-imx8mn.c
+++ b/drivers/clk/imx/clk-imx8mn.c
@@ -570,9 +570,14 @@  MODULE_DEVICE_TABLE(of, imx8mn_clk_of_match);
 
 static struct platform_driver imx8mn_clk_driver = {
 	.probe = imx8mn_clocks_probe,
 	.driver = {
 		.name = "imx8mn-ccm",
+		/*
+		 * Disable bind attributes: clocks are not removed and
+		 * reloading the driver will crash or break devices.
+		 */
+		.suppress_bind_attrs = true,
 		.of_match_table = of_match_ptr(imx8mn_clk_of_match),
 	},
 };
 module_platform_driver(imx8mn_clk_driver);
diff --git a/drivers/clk/imx/clk-imx8mq.c b/drivers/clk/imx/clk-imx8mq.c
index 5f10a606d836..2168fe6cf7e4 100644
--- a/drivers/clk/imx/clk-imx8mq.c
+++ b/drivers/clk/imx/clk-imx8mq.c
@@ -607,9 +607,14 @@  MODULE_DEVICE_TABLE(of, imx8mq_clk_of_match);
 
 static struct platform_driver imx8mq_clk_driver = {
 	.probe = imx8mq_clocks_probe,
 	.driver = {
 		.name = "imx8mq-ccm",
+		/*
+		 * Disable bind attributes: clocks are not removed and
+		 * reloading the driver will crash or break devices.
+		 */
+		.suppress_bind_attrs = true,
 		.of_match_table = of_match_ptr(imx8mq_clk_of_match),
 	},
 };
 module_platform_driver(imx8mq_clk_driver);