Re: [PATCH 0/1] lockdep: Kill held_lock->check and "int check" argof __lock_acquire()

From: Peter Zijlstra
Date: Sun Jan 12 2014 - 15:01:33 EST


On Sun, Jan 12, 2014 at 06:45:32PM +0100, Oleg Nesterov wrote:
> But could someone please explain me what should lockdep_no_validate
> actually do? 1704f47b5 "lockdep: Add novalidate class for dev->mutex
> conversion" doesn't tell which kind of warnings it tries to avoid,
> and it looks buggy (see another email from me).

It should disable lock-order checks for the locks that set that as
class. So we can still do the simple checks like detect if we free
memory with a held lock in and make sure we do not return to userspace
with a held lock; but the class should not participate in the lock
graph.

I'll have a look at your earlier email again; I did note the question
but it slipped my mind :/
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