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Date:   Thu, 26 Oct 2023 14:13:13 +0900
From:   Sergey Senozhatsky <senozhatsky@chromium.org>
To:     John Johansen <john.johansen@canonical.com>
Cc:     Sergey Senozhatsky <senozhatsky@chromium.org>,
        Anil Altinay <aaltinay@google.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        LKLM <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Tomasz Figa <tfiga@chromium.org>,
        linux-security-module@vger.kernel.org
Subject: Re: [PATCH v5 0/4] apparmor: cache buffers on percpu list if there
 is lock, contention
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On (23/10/17 02:21), John Johansen wrote:
> > > yeah, testing help is always much appreciated. I have a v4, and I am
> > > working on 3 alternate version to compare against, to help give a better
> > > sense if we can get away with simplifying or tweak the scaling.
> > > 
> > > I should be able to post them out some time tonight.
> > 
> > Hi John,
> > 
> > Did you get a chance to post v4? I may be able to give it some testing
> > on our real-life case.
> 
> sorry yes, how about a v5. That is simplified with 3 follow on patches
> that aren't strictly necessary, but some combination of them might be
> better than just the base patch, but splitting them out makes the
> individual changes easier to review.

Sorry for late reply. So I gave it a try but, apparently, our build
environment has changed quite significantly since the last time I
looked into it.

I don't see that many aa_get/put_buffer() anymore. apparmor buffer
functions are mostly called form the exec path:

	security_bprm_creds_for_exec()
	 apparmor_bprm_creds_for_exec()
	  make_vfsuid()
	   aa_get_buffer()

As for vfs_statx()->...->apparmor_inode_getattr()->aa_path_perm(),
that path is bpf_lsm_inode_getsecid() now.