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Date:   Thu, 8 Aug 2019 19:45:23 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     John Ogness <john.ogness@linutronix.de>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andrea Parri <andrea.parri@amarulasolutions.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Brendan Higgins <brendanhiggins@google.com>
Subject: Re: [RFC PATCH v4 9/9] printk: use a new ringbuffer implementation
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On Thu, 8 Aug 2019 16:33:20 -0700
Linus Torvalds <torvalds@linux-foundation.org> wrote:


> To which the obvious solution is "just use a different buffer for the
> next boot". But that brings up the *second* big issue with a
> reboot-safe buffer: it can't just be anywhere. Not only do you have to
> have some way to find the old one, the actual location may end up
> being basically fixed by hardware or firmware.

Could we possibly have a magic value in some location that if it is
set, we know right away that the buffer here has data from the last
reboot, and we read it out into a safe location before we start using
it again?

-- Steve