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Date: Tue, 9 Apr 2024 16:37:10 -0700
From: Kees Cook <keescook@chromium.org>
To: "Luck, Tony" <tony.luck@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>,
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	Will Deacon <will@kernel.org>
Subject: Re: [POC][RFC][PATCH 0/2] pstore/mm/x86: Add wildcard memmap to map
 pstore consistently
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On Tue, Apr 09, 2024 at 10:25:33PM +0000, Luck, Tony wrote:
> >> 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.
> 
> Which systems does this work on? I'd assume that servers (and anything
> else with ECC memory) would nuke contents while resetting ECC to clean
> state.

Do ECC servers wipe their RAM by default? I know that if you build with
CONFIG_RESET_ATTACK_MITIGATION=y on an EFI system that supports the
MemoryOverwriteRequestControl EFI variable you'll get a RAM wipe...

-- 
Kees Cook