| Message ID | 20230619160249.10414-1-mans@mansr.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | backlight: led_bl: take led_access lock when required | expand |
On Mon, Jun 19, 2023 at 05:02:49PM +0100, Mans Rullgard wrote: > The led_access lock must be held when calling led_sysfs_enable() and > led_sysfs_disable(). This fixes warnings such as this: > > [ 2.432495] ------------[ cut here ]------------ > [ 2.437316] WARNING: CPU: 0 PID: 22 at drivers/leds/led-core.c:349 led_sysfs_disable+0x54/0x58 > [ 2.446105] Modules linked in: > [ 2.449218] CPU: 0 PID: 22 Comm: kworker/u2:1 Not tainted 6.3.8+ #1 > [ 2.456268] Hardware name: Generic AM3517 (Flattened Device Tree) > [ 2.462402] Workqueue: events_unbound deferred_probe_work_func > [ 2.468353] unwind_backtrace from show_stack+0x10/0x14 > [ 2.473632] show_stack from dump_stack_lvl+0x24/0x2c > [ 2.478759] dump_stack_lvl from __warn+0x9c/0xc4 > [ 2.483551] __warn from warn_slowpath_fmt+0x64/0xc0 > [ 2.488586] warn_slowpath_fmt from led_sysfs_disable+0x54/0x58 > [ 2.494567] led_sysfs_disable from led_bl_probe+0x20c/0x3b0 > [ 2.500305] led_bl_probe from platform_probe+0x5c/0xb8 > [ 2.505615] platform_probe from really_probe+0xc8/0x2a0 > [ 2.510986] really_probe from __driver_probe_device+0x88/0x19c > [ 2.516967] __driver_probe_device from driver_probe_device+0x30/0xcc > [ 2.523498] driver_probe_device from __device_attach_driver+0x94/0xc4 > [ 2.530090] __device_attach_driver from bus_for_each_drv+0x80/0xcc > [ 2.536437] bus_for_each_drv from __device_attach+0xf8/0x19c > [ 2.542236] __device_attach from bus_probe_device+0x8c/0x90 > [ 2.547973] bus_probe_device from deferred_probe_work_func+0x80/0xb0 > [ 2.554504] deferred_probe_work_func from process_one_work+0x228/0x4c0 > [ 2.561187] process_one_work from worker_thread+0x1fc/0x4d0 > [ 2.566925] worker_thread from kthread+0xb4/0xd0 > [ 2.571685] kthread from ret_from_fork+0x14/0x2c > [ 2.576446] Exception stack(0xd0079fb0 to 0xd0079ff8) > [ 2.581573] 9fa0: 00000000 00000000 00000000 00000000 > [ 2.589813] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > [ 2.598052] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 > [ 2.604888] ---[ end trace 0000000000000000 ]--- > > > Signed-off-by: Mans Rullgard <mans@mansr.com> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Daniel.
On Mon, 19 Jun 2023, Mans Rullgard wrote: > The led_access lock must be held when calling led_sysfs_enable() and > led_sysfs_disable(). This fixes warnings such as this: > > [ 2.432495] ------------[ cut here ]------------ > [ 2.437316] WARNING: CPU: 0 PID: 22 at drivers/leds/led-core.c:349 led_sysfs_disable+0x54/0x58 > [ 2.446105] Modules linked in: > [ 2.449218] CPU: 0 PID: 22 Comm: kworker/u2:1 Not tainted 6.3.8+ #1 > [ 2.456268] Hardware name: Generic AM3517 (Flattened Device Tree) > [ 2.462402] Workqueue: events_unbound deferred_probe_work_func > [ 2.468353] unwind_backtrace from show_stack+0x10/0x14 > [ 2.473632] show_stack from dump_stack_lvl+0x24/0x2c > [ 2.478759] dump_stack_lvl from __warn+0x9c/0xc4 > [ 2.483551] __warn from warn_slowpath_fmt+0x64/0xc0 > [ 2.488586] warn_slowpath_fmt from led_sysfs_disable+0x54/0x58 > [ 2.494567] led_sysfs_disable from led_bl_probe+0x20c/0x3b0 > [ 2.500305] led_bl_probe from platform_probe+0x5c/0xb8 > [ 2.505615] platform_probe from really_probe+0xc8/0x2a0 > [ 2.510986] really_probe from __driver_probe_device+0x88/0x19c > [ 2.516967] __driver_probe_device from driver_probe_device+0x30/0xcc > [ 2.523498] driver_probe_device from __device_attach_driver+0x94/0xc4 > [ 2.530090] __device_attach_driver from bus_for_each_drv+0x80/0xcc > [ 2.536437] bus_for_each_drv from __device_attach+0xf8/0x19c > [ 2.542236] __device_attach from bus_probe_device+0x8c/0x90 > [ 2.547973] bus_probe_device from deferred_probe_work_func+0x80/0xb0 > [ 2.554504] deferred_probe_work_func from process_one_work+0x228/0x4c0 > [ 2.561187] process_one_work from worker_thread+0x1fc/0x4d0 > [ 2.566925] worker_thread from kthread+0xb4/0xd0 > [ 2.571685] kthread from ret_from_fork+0x14/0x2c > [ 2.576446] Exception stack(0xd0079fb0 to 0xd0079ff8) > [ 2.581573] 9fa0: 00000000 00000000 00000000 00000000 > [ 2.589813] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > [ 2.598052] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 > [ 2.604888] ---[ end trace 0000000000000000 ]--- > > > Signed-off-by: Mans Rullgard <mans@mansr.com> > --- > drivers/video/backlight/led_bl.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) Applied, thanks
diff --git a/drivers/video/backlight/led_bl.c b/drivers/video/backlight/led_bl.c index f54d256e2d54..7d02deb3444a 100644 --- a/drivers/video/backlight/led_bl.c +++ b/drivers/video/backlight/led_bl.c @@ -209,8 +209,11 @@ static int led_bl_probe(struct platform_device *pdev) return PTR_ERR(priv->bl_dev); } - for (i = 0; i < priv->nb_leds; i++) + for (i = 0; i < priv->nb_leds; i++) { + mutex_lock(&priv->leds[i]->led_access); led_sysfs_disable(priv->leds[i]); + mutex_unlock(&priv->leds[i]->led_access); + } backlight_update_status(priv->bl_dev);
The led_access lock must be held when calling led_sysfs_enable() and led_sysfs_disable(). This fixes warnings such as this: [ 2.432495] ------------[ cut here ]------------ [ 2.437316] WARNING: CPU: 0 PID: 22 at drivers/leds/led-core.c:349 led_sysfs_disable+0x54/0x58 [ 2.446105] Modules linked in: [ 2.449218] CPU: 0 PID: 22 Comm: kworker/u2:1 Not tainted 6.3.8+ #1 [ 2.456268] Hardware name: Generic AM3517 (Flattened Device Tree) [ 2.462402] Workqueue: events_unbound deferred_probe_work_func [ 2.468353] unwind_backtrace from show_stack+0x10/0x14 [ 2.473632] show_stack from dump_stack_lvl+0x24/0x2c [ 2.478759] dump_stack_lvl from __warn+0x9c/0xc4 [ 2.483551] __warn from warn_slowpath_fmt+0x64/0xc0 [ 2.488586] warn_slowpath_fmt from led_sysfs_disable+0x54/0x58 [ 2.494567] led_sysfs_disable from led_bl_probe+0x20c/0x3b0 [ 2.500305] led_bl_probe from platform_probe+0x5c/0xb8 [ 2.505615] platform_probe from really_probe+0xc8/0x2a0 [ 2.510986] really_probe from __driver_probe_device+0x88/0x19c [ 2.516967] __driver_probe_device from driver_probe_device+0x30/0xcc [ 2.523498] driver_probe_device from __device_attach_driver+0x94/0xc4 [ 2.530090] __device_attach_driver from bus_for_each_drv+0x80/0xcc [ 2.536437] bus_for_each_drv from __device_attach+0xf8/0x19c [ 2.542236] __device_attach from bus_probe_device+0x8c/0x90 [ 2.547973] bus_probe_device from deferred_probe_work_func+0x80/0xb0 [ 2.554504] deferred_probe_work_func from process_one_work+0x228/0x4c0 [ 2.561187] process_one_work from worker_thread+0x1fc/0x4d0 [ 2.566925] worker_thread from kthread+0xb4/0xd0 [ 2.571685] kthread from ret_from_fork+0x14/0x2c [ 2.576446] Exception stack(0xd0079fb0 to 0xd0079ff8) [ 2.581573] 9fa0: 00000000 00000000 00000000 00000000 [ 2.589813] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 2.598052] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 2.604888] ---[ end trace 0000000000000000 ]--- Signed-off-by: Mans Rullgard <mans@mansr.com> --- drivers/video/backlight/led_bl.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)