12/28/2011 11:53 PM, intrigeri:
> Hi,
>
> as far as Tails is concerned, I'm thinking of:
> - on 64-bit hardware, kexec to a 64-bit kernel and use memtest=
> there; Maxim, have you confirmed by actual testing this works for
> more than 3GB?
I just tried your implementation of this in the bugfix/kexec_amd64
branch on bare-metal, and I'm sad to say that it's not working. The
following lists the number of occurrences of the pattern for certain
segments of memory (in megabytes):
0 - 10: 348
10 - 20: 244233
30 - 200: 0
200 - 600: each 10 MB block in this segment has ~655K hits*
600 -2180: 0
2180-2190: 511
2190-2330: 0
2330-2340: 174
Rest : 0
* Note that a 10 MB block can contain at most 655360 occurrences of a
16 byte pattern (like ours) so this memory segment is completely
untouched by the wipe.
> - on 32-bit hardware, kexec to a 32-bit kernel and go on using
> sdmem; it's still limited to 3GB, but arguably 32-bit computers
> with more than 3GB of RAM are very rare.
Didn't test.
