Re: Kernel drivers and IOCTLs

On Tue, Jan 21, 2020 at 10:27:01PM -0600, WyoFlippa wrote:

Hi,

I'm working on a driver that would verify a Linux or U-Boot image is secure and I need to pass parameters such as the public key, starting address, etc. I'd heard in talking to developers that IOCTLs are frowned upon. I also found this article that seems to indicate that using sysfs or proc is a better way to go.

https://www.linuxjournal.com/article/8110

but then I see this article from 2013 which is more recent than the article.

https://www.kernel.org/doc/html/latest/process/botching-up-ioctls.html

So are IOCTLs discouraged or not?

They are discouraged, except when they are necessary :) It all depends on exactly what you are trying to do. greg k-h