Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Fri, 26 May 2023 17:43:55 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Lorenz Bauer <lmb@isovalent.com>
Cc:     Sasha Levin <sashal@kernel.org>, linux-kernel@vger.kernel.org,
        stable@vger.kernel.org, Martin KaFai Lau <martin.lau@kernel.org>,
        ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org,
        shuah@kernel.org, yhs@fb.com, eddyz87@gmail.com, sdf@google.com,
        error27@gmail.com, iii@linux.ibm.com, memxor@gmail.com,
        bpf@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH AUTOSEL 6.2 08/30] selftests/bpf: check that modifier
 resolves after pointer
Message-ID: <2023052647-tacking-wince-85c5@gregkh>
References: <20230320005258.1428043-1-sashal@kernel.org>
 <20230320005258.1428043-8-sashal@kernel.org>
 <CAN+4W8g6AcQQWe7rrBVOFYoqeQA-1VbUP_W7DPS3q0k-czOLfg@mail.gmail.com>
 <ZBiAPngOtzSwDhFz@kroah.com>
 <CAN+4W8jAyJTdFL=tgp3wCpYAjGOs5ggo6vyOg8PbaW+tJP8TKA@mail.gmail.com>
 <CAN+4W8j5qe6p3YV90g-E0VhV7AmYyAvt0z50dfDSombbGghkww@mail.gmail.com>
 <2023041100-oblong-enamel-5893@gregkh>
 <CAN+4W8hmSgbb-wO4da4A=6B4y0oSjvUTTVia_0PpUXShP4NX4Q@mail.gmail.com>
 <2023052435-xbox-dislike-0ab2@gregkh>
 <CAN+4W8iMcwwVjmSekZ9txzZNxOZ0x98nBXo4cEoTU9G2zLe8HA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <CAN+4W8iMcwwVjmSekZ9txzZNxOZ0x98nBXo4cEoTU9G2zLe8HA@mail.gmail.com>
Precedence: bulk

On Wed, May 24, 2023 at 06:04:43PM +0100, Lorenz Bauer wrote:
> On Wed, May 24, 2023 at 5:04 PM Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > Great, any specific commits that fix this issue would be appreciated to
> > be pointed at so we can apply them.
> 
> The problem was introduced by commit f4b8c0710ab6 ("selftests/bpf: Add
> verifier test for release_reference()") in your tree. Seems like
> fixup_map_ringbuf was introduced in upstream commit 4237e9f4a962
> ("selftests/bpf: Add verifier test for PTR_TO_MEM spill") but that
> wasn't backported.

So what tree(s) does this need to be backported to?  I'm confused, this
is a 6.2 email thread which is long end-of-life.

> To restate my original question: how can we avoid breaking BPF
> selftests? From personal experience this happens somewhat regularly.

It can be avoided by people testing and letting me know when things
break :)

thanks,

greg k-h