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Date:   Wed, 4 Mar 2020 17:11:23 -0800
From:   Matthew Wilcox <willy@infradead.org>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Aleksa Sarai <cyphar@cyphar.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [RFC][PATCHSET] sanitized pathwalk machinery (v3)
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On Wed, Mar 04, 2020 at 09:00:31PM +0000, Al Viro wrote:
> On Wed, Mar 04, 2020 at 09:59:46PM +1100, Aleksa Sarai wrote:
> 
> > > FWIW, I'm putting together some litmus tests for pathwalk semantics -
> > > one of the things I'd like to discuss at LSF; quite a few codepaths
> > > are simply not touched by anything in xfstests.
> > 
> > I won't be at LSF unfortunately, but this is something I would be very
> > interested in helping with -- one of the things I've noticed is the lack
> > of a test-suite for some of the more generic VFS bits (such as namei).
> 
> BTW, has anyone tried to run tests with oprofile and see how much of the
> core kernel gets exercised?  That looks like an obvious thing to try -
> at least the places outside of spin_lock_irq() ought to get lit after
> a while...
> 
> Have any CI folks tried doing that, or am I missing some obvious reason
> why that is not feasible?

I don't know about oprofile, but LTP got their gcov patches merged
into 2.6.31:

http://ltp.sourceforge.net/coverage/gcov.php