2007-09-20 11:39:18

by Tomasz Chmielewski

[permalink] [raw]
Subject: patch/option to wipe memory at boot?

> Is there a patch or a boot option or something which wipes all
> available (physical) RAM at boot (or better, fills it with a fixed
> signature like 0xdeadbeef)? I'm getting phony ECC errors and I'd like
> to test whether they go away when the RAM is properly initialized.
> Also, I'd like to know exactly which parts of RAM are being used and
> which are untouched since boot (hence the 0xdeadbeef signature).
>
> If this patch/option doesn't exist, can anyone give me a hint as to
> where and how it would be best to add this? (I'm afraid I'm very
> ignorant as to how Linux sets up its RAM mapping.) I'm concerned
> about x86 and x86_64.
>
> PS: I'm not finicky: it's all right if a couple of megabytes at the
> bottom of RAM are not scrubbed (I'm more interested about the top
> gigabyte-or-so), especially if they're guaranteed to be used by the
> kernel.

As a side note to what others said, you can always use initrd/initramfs
to start your favourite program that wipes the memory...


--
Tomasz Chmielewski
http://blog.wpkg.org