Re: Fix for SMP deadlock in autofs4

From: Linus Torvalds (torvalds@transmeta.com)
Date: Fri Apr 20 2001 - 14:01:37 EST


On Fri, 20 Apr 2001, Jeremy Fitzhardinge wrote:
>
> This is a fix for a potential deadlock in autofs4's expire routine.

It's wrong.

I don't think we should be able to do a mntput() _either_ inside the
spinlock. The filesystem should not "know" that mntput is safe.

For this reason I don't think "dput_locked()" is the right answer either.

Why are we doing the mntget/dget at all? We hold the spinlock, so we know
they are not going away. Not doing the mntget/dget means that we (a) run
faster and (b) don't have the bug, because we don't need to put the damn
things.

Comments?

                Linus

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Mon Apr 23 2001 - 21:00:37 EST