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Subject: Re: [PATCH 0/2] introduce DUMP_PREFIX_UNHASHED for hex dumps
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Petr Mladek <pmladek@suse.com>, roman.fietze@magna.com,
        keescook@chromium.org, Steven Rostedt <rostedt@goodmis.org>,
        John Ogness <john.ogness@linutronix.de>, linux-mm@kvack.org,
        Akinobu Mita <akinobu.mita@gmail.com>
References: <20210116220950.47078-1-timur@kernel.org>
 <20210118182635.GD2260413@casper.infradead.org>
From:   Timur Tabi <timur@kernel.org>
Message-ID: <ed7e0656-9271-3ccf-ef88-153da1ee31c9@kernel.org>
Date:   Mon, 18 Jan 2021 13:03:49 -0600
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On 1/18/21 12:26 PM, Matthew Wilcox wrote:
> Don't make it easy.  And don't make it look like they're doing
> something innocent.  DUMP_PREFIX_SECURITY_HOLE would be OK
> by me.  DUMP_PREFIX_LEAK_INFORMATION would work fine too.
> DUMP_PREFIX_MAKE_ATTACKERS_LIFE_EASY might be a bit too far.

It's already extremely easy to replace %p with %px in your own printks, 
so I don't really understand your argument.

Seriously, this patch should not be so contentious.  If you want hashed 
addresses, then nothing changes.  If you need unhashed addresses while 
debugging, then use DUMP_PREFIX_UNHASHED.  Just like you can use %px in 
printk.  I never use %p in my printks, but then I never submit code 
upstream that prints addresses, hashed or unhashed.