RE: [PATCH v5 06/13] lockdep: Implement crossrelease feature

byungchul.park
2017-03-02T06:15:40Z

> -----Original Message-----
> From: Matthew Wilcox [mailto:willy@infradead.org]
> Sent: Thursday, March 02, 2017 1:20 PM
> To: Peter Zijlstra
> Cc: Byungchul Park; mingo@kernel.org; tglx@linutronix.de;
> walken@google.com; boqun.feng@gmail.com; kirill@shutemov.name; linux-
> kernel@vger.kernel.org; linux-mm@kvack.org; iamjoonsoo.kim@lge.com;
> akpm@linux-foundation.org; npiggin@gmail.com
> Subject: Re: [PATCH v5 06/13] lockdep: Implement crossrelease feature
>
> On Tue, Feb 28, 2017 at 07:15:47PM +0100, Peter Zijlstra wrote:
> > (And we should not be returning to userspace with locks held anyway --
> > lockdep already has a check for that).
>
> Don't we return to userspace with page locks held, eg during async
> directio?

Hello,

I think that the check when returning to user with crosslocks held
should be an exception. Don't you think so?

Thanks,
Byungchul