Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 10 Feb 2021 11:46:33 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc:     Timur Tabi <timur@kernel.org>, Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Matthew Wilcox <willy@infradead.org>,
        akpm@linux-foundation.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        roman.fietze@magna.com, Kees Cook <keescook@chromium.org>,
        John Ogness <john.ogness@linutronix.de>,
        akinobu.mita@gmail.com, glider@google.com,
        Andrey Konovalov <andreyknvl@google.com>,
        Marco Elver <elver@google.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Pavel Machek <pavel@ucw.cz>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH 0/3][RESEND] add support for never printing hashed
 addresses
Message-ID: <20210210114633.1b755f6e@gandalf.local.home>
In-Reply-To: <e996ff2f-d350-1399-bb6b-8373bf70e687@i-love.sakura.ne.jp>
References: <20210210051814.845713-1-timur@kernel.org>
        <6da0be5a-7cb0-4943-e61f-7c3275e60cb6@i-love.sakura.ne.jp>
        <20210210111836.2468f10a@gandalf.local.home>
        <e996ff2f-d350-1399-bb6b-8373bf70e687@i-love.sakura.ne.jp>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Thu, 11 Feb 2021 01:39:41 +0900
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote:

> On 2021/02/11 1:18, Steven Rostedt wrote:
> > The point of this exercise is to be able to debug the *same* kernel that
> > someone is having issues with. And this is to facilitate that debugging.  
> 
> That's too difficult to use. If a problem is not reproducible, we will have
> no choice but always specify "never hash pointers" command line option. If a
> problem is reproducible, we can rebuild that kernel with "never hash pointers"
> config option turned on.

Now the question is, why do you need the unhashed pointer?

Currently, the instruction pointer is what is fine right? You get the
a function and its offset. If there's something that is needed, perhaps we
should look at how to fix that, instead of just unhashing all pointers by
default.

-- Steve