Re: Memory Trauam

Alan Cox (
Tue, 19 Nov 1996 19:27:22 +0000 (GMT)

> So here's my dilemma: why didn't memtest 1.1 notice the bad ram? This
> wasn't the type of problem that showed up intermittedly: after booting
> my kernel INIT would ALWAYS fail.... ALWAYS. As would initrd.

memset86 tests certain patterns. It can't test some things like memory
that is only marginal enough to fail if a bus mastering DMA transfer
(eg off a disk) and a main memory access arrive back to back in the right

> I believe we should look into providing another tool for detecting
> these errors. Not a part of the true kernel, but perhaps derived from
> it. At least that way, hopefully, we can get consistent errors from
> the kernel and memtest.

Testing memory is a very very highly complex art. You can't do a real
test on a board without a lot of advanced tools and circuitry, the
processor unplugged etc.