Re: [PATCH v3 0/4] kmod: help make deterministic

From: Petr Mladek
Date: Tue Jun 27 2017 - 04:14:20 EST


On Tue 2017-06-27 02:27:44, Luis R. Rodriguez wrote:
> On Tue, Jun 27, 2017 at 12:44:42AM +0200, Luis R. Rodriguez wrote:
> > On Mon, Jun 26, 2017 at 11:37:36PM +0200, Jessica Yu wrote:
> > > +++ Kees Cook [20/06/17 17:23 -0700]:
> > > > On Tue, Jun 20, 2017 at 1:56 PM, Luis R. Rodriguez <mcgrof@xxxxxxxxxx> wrote:
> > > > > On Fri, May 26, 2017 at 02:12:24PM -0700, Luis R. Rodriguez wrote:
> > > > > > Luis R. Rodriguez (4):
> > > > > > module: use list_for_each_entry_rcu() on find_module_all()
> > > > > > kmod: reduce atomic operations on kmod_concurrent and simplify
> > > > > > kmod: add test driver to stress test the module loader
> > > > > > kmod: throttle kmod thread limit
> > > > >
> > > > > About a month now with no further nitpicks. What tree should these changes
> > > > > go through if there are no issues? Andrew's, Jessica's ?
> > > >
> > > > Seems like going through Jessica's would make the most sense?
> > >
> > > Would be happy to take patches 01 (which I need to anyway), 02,
> > > possibly 04 if decoupled from the test driver (03).
> >
> > Feel free to decouple it, but note that then the commit log must then be
> > changed. My own take is this fix is not so critical as it is a corner case, so
> > I have instead preferred to couple in the test case and respective fix
> > together. I'll leave it up to you how to proceed.
>
> Note: Linus noted swait is actually very special use-case [0] so I'd hate to
> add a new use case not vetted for. This use case on kmod.c really does *not*
> require anything but a simple wait though, so really am inclined to let that
> through unless I hear back...
>
> [0] https://lkml.kernel.org/r/20170627001534.GK21846@xxxxxxxxxxxxx

Heh, I was not aware of this special case either. The welcoming
comment of the swait API confused me as well.

In this light, I suggest to switch the patch to using the normal wait API.

Best Regards,
Petr