Re: [PATCH] nvme: fix lockdep warning in nvme_mpath_clear_current_path

From: Johannes Thumshirn
Date: Mon May 14 2018 - 09:35:41 EST


On Mon, May 14, 2018 at 06:31:05AM -0700, Paul E. McKenney wrote:
> If you are just looking at the value of an RCU-protected pointer, then
> using rcu_access_pointer() will cause RCU to just read out the value
> and otherwise keeps its mouth shut.
>
> If you use rcu_access_pointer() and later dereference the value without
> protection, you will of course get what you deserve, good and hard. ;-)

Thanks Paul.

Christoph, I'll be sending the v2 probably tomorrow as I have more
lockdep fixes for nvme in the pipe and I'll send them out as a
complete series.

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