Re: 2.6.21-rc suspend regression: sysfs deadlock

Alan Stern
2007-03-13T21:20:46Z

On Tue, 13 Mar 2007, Hugh Dickins wrote:

> On Tue, 13 Mar 2007, Alan Stern wrote:
> >
> > On the other hand, a quick survey of the kernel source shows that
> > DEVICE_ATTR is used over 1500 times. Auditing all of them is not a job
> > for the faint-of-heart!
>
> Indeed, and faint-hearted Hugh wasn't intending to do so: but
> stout-hearted Alan will need to, won't he, before his patch can go in?

Allow me to point out that the original patch is Oliver's (although I
helped), and it doesn't need to go in -- it needs not to be removed.

Furthermore, I have better things to do with the next month of my time
than auditing hundreds of routines I don't understand for behavior I
probably won't be able to recognize. (Although at 50 a day... hmmm,
maybe.)

This sounds more like a job for kernel-janitors!

On Tue, 13 Mar 2007, Dmitry Torokhov wrote:

> I think we could rely on subsystems maintainers to let us know if
> there are potential problems. For example I can tell that neither
> input, serio nor gameport subsystems use sysfs to destroy their
> devices (action on sysfs may cause some other device to be destroyed
> but that should be ok, only self-destruction is not allowed, right?)

Very good points. USB doesn't do anything like that either. And right,
it's okay for a method to destroy other devices; it just can't do anything
that would lead to its own unregistration.

Alan Stern