Re: [DMARC error][SPF error] Re: [PATCH v4 00/10] devm_led_classdev_register() usage problem

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hello Andy.


I haven't lose hope for the devm_mutex thing and keep pinging those guys from time to time.

Sure I can single out the fix-only patch I'll do it tomorrow.


On 2/9/24 20:11, Andy Shevchenko wrote:
On Thu, Dec 21, 2023 at 03:11:11PM +0000, Lee Jones wrote:
On Thu, 14 Dec 2023, George Stark wrote:

This patch series fixes the problem of devm_led_classdev_register misusing.

The basic problem is described in [1]. Shortly when devm_led_classdev_register()
is used then led_classdev_unregister() called after driver's remove() callback.
led_classdev_unregister() calls driver's brightness_set callback and that callback
may use resources which were destroyed already in driver's remove().

After discussion with maintainers [2] [3] we decided:
1) don't touch led subsytem core code and don't remove led_set_brightness() from it
but fix drivers
2) don't use devm_led_classdev_unregister

So the solution is to use devm wrappers for all resources
driver's brightness_set() depends on. And introduce dedicated devm wrapper
for mutex as it's often used resource.

[1] https://lore.kernel.org/lkml/8704539b-ed3b-44e6-aa82-586e2f895e2b@xxxxxxxxxxxxxxxxx/T/
[2] https://lore.kernel.org/lkml/8704539b-ed3b-44e6-aa82-586e2f895e2b@xxxxxxxxxxxxxxxxx/T/#mc132b9b350fa51931b4fcfe14705d9f06e91421f
[3] https://lore.kernel.org/lkml/8704539b-ed3b-44e6-aa82-586e2f895e2b@xxxxxxxxxxxxxxxxx/T/#mdbf572a85c33f869a553caf986b6228bb65c8383

...

FYI: I'll conduct my review once the locking side is settled.

To reduce burden can you apply the first one? It's a fix.


--
Best regards
George




[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux