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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 23 May 2018 09:26:35 -0700
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Subject: Re: write_lock_irq(&tasklist_lock)
To:     Will Deacon <will.deacon@arm.com>
Cc:     psodagud@codeaurora.org, Kees Cook <keescook@chromium.org>,
        Andy Lutomirski <luto@amacapital.net>,
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        Andrew Morton <akpm@linux-foundation.org>,
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On Wed, May 23, 2018 at 8:35 AM Will Deacon <will.deacon@arm.com> wrote:

> In other words, qrwlock requires consistent locking order wrt spinlocks.

I *thought* lockdep already tracked and detected this. Or is that only with
with the sleeping versions?

But yes, that's equivalent to the irq-unfairness thing we have a special
case for.

              Linus