Re: [announce] "kill the Big Kernel Lock (BKL)" tree

[corbet@lwn.net (Jonathan Corbet)]

Linus Torvalds <torvalds@linux-foundation.org> wrote:

> I don't think there are *that* many. I found only 83 instances of 
> "register_chrdev()" in the kernel, so the open methods should be pretty 
> limited.

There's the drivers calling cdev_add() directly as well - another
40ish.  Still not a huge list, I guess.
 
> So it literally should be:
>  - remove one lock_kernel/unlock_kernel pair in fs/char_dev.c
>  - add max 83 pairs in the places that register those things
>  - external modules will need to add it themselves some day.

This is all certainly doable, but it leaves me with one concern: there
will be no signal to external module maintainers that the change needs
to be made.  So, beyond doubt, quite a few of them will just continue to
be shipped unfixed - and they will still run.  If any of them actually
*need* the BKL, something awful may happen to somebody someday.

jon