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Date: Thu, 6 Jun 2024 10:50:13 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: "Luck, Tony" <tony.luck@intel.com>
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Subject: Re: [PATCH 1/2] mm/memblock: Add "reserve_mem" to reserved named
 memory at boot up
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On Tue, 4 Jun 2024 16:05:04 +0000
"Luck, Tony" <tony.luck@intel.com> wrote:

> > I have been using this on two different test machines, as well as a
> > chromebook, and it appears to work on all ofthem. As well as for VMs. I
> > plan on adding this to my workstation and server too (they use EFI).  
> 
> I think that BIOS on Intel servers with ECC memory will stomp on all
> memory (to ensure that ECC bits are all set to good values). There
> might be a "fast boot" BIOS option to skip this (but using it leaves you
> vulnerable after a crash due to ECC fail to hit the same error again).
> 

Talking with some people that are interested in this, they told me that
those servers (the ones that take several minutes to boot up) usually
use kexec to reboot. Even after a crash (with or without kdump). In
those cases, they said this would likely work for them.

Again, this isn't fool proof nor guaranteed. It's a best effort
approach that, at least for my use case, works most of the time.

-- Steve