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Date: Tue, 9 Apr 2024 15:19:48 -0700
From: Kees Cook <keescook@chromium.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	Masami Hiramatsu <mhiramat@kernel.org>,
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	"Liam R. Howlett" <Liam.Howlett@oracle.com>,
	Vlastimil Babka <vbabka@suse.cz>,
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	Linus Torvalds <torvalds@linuxfoundation.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>
Subject: Re: [POC][RFC][PATCH 0/2] pstore/mm/x86: Add wildcard memmap to map
 pstore consistently
Message-ID: <202404091519.B7B2221@keescook>
References: <20240409210254.660888920@goodmis.org>
 <20240409172358.34ea19f0@gandalf.local.home>
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On Tue, Apr 09, 2024 at 05:23:58PM -0400, Steven Rostedt wrote:
> On Tue, 09 Apr 2024 17:02:54 -0400
> Steven Rostedt <rostedt@goodmis.org> wrote:
> 
> >   memmap=12M*4096:oops   ramoops.mem_name=oops
> 
> I forgot to mention that this makes it trivial for any machine that doesn't
> clear memory on soft-reboot, to enable console ramoops (to have access to
> the last boot dmesg without needing serial).
> 
> I tested this on a couple of my test boxes and on QEMU, and it works rather
> well.

I've long wanted a "stable for this machine and kernel" memory region
like this for pstore. It would make testing much easier.

-- 
Kees Cook