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Date:   Sat, 23 Jul 2022 16:05:16 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Siddh Raman Pant <code@siddh.me>
Cc:     David Howells <dhowells@redhat.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        linux-security-modules <linux-security-module@vger.kernel.org>,
        keyrings <keyrings@vger.kernel.org>,
        linux-kernel-mentees 
        <linux-kernel-mentees@lists.linuxfoundation.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] keys/keyctl: Use kfree_rcu instead of kfree
Message-ID: <YtwAHGISvlgXgXZM@kroah.com>
References: <20220723135035.199188-1-code@siddh.me>
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On Sat, Jul 23, 2022 at 07:20:35PM +0530, Siddh Raman Pant via Linux-kernel-mentees wrote:
> In keyctl_watch_key, use kfree_rcu() for freeing watch and wlist
> as they support RCU and have an rcu_head in the struct definition.

That does not explain why this change is needed.  What problem does this
solve?  Why use RCU if you don't have to?  What functionality did you
just change in this commit and why?

And how was this tested?

thanks,

greg k-h