linux-kernel - Re: Testing RAM from userspace / question about memmap= arguments

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20071222205432.GA2221@elf.ucw.cz>
Date:	Sat, 22 Dec 2007 21:54:32 +0100
From:	Pavel Machek <pavel@....cz>
To:	David Newall <david@...idnewall.com>
Cc:	Richard D <richard@...unus.com>,
	'Matthew Bloch' <matthew@...emark.co.uk>,
	linux-kernel@...r.kernel.org
Subject: Re: Testing RAM from userspace / question about memmap= arguments

On Sun 2007-12-23 07:06:58, David Newall wrote:
> Pavel Machek wrote:
>> memtest has following problems:
>>
>> 	0) it is kind of hard to run memtest over ssh
>>   
>
> It's kind of hard to run anything over SSH if it has to be run before 
> userspace is up.  But the kernel can collect results from a modified 
> memtest, after it chains back.

memtest can be ran from userspace, that's the point.

>> 	1) if linux fixes some problem with PCI quirk or microcode
>> 	upload, memtest will not see the fix
>>   
>
> What are you saying?  Linux is going to fix faulty RAM?

Yes, that's what CPU microcode update is for. And I want to test my
RAM with up-to-date microcode.

>> 	2) if memory only fails while something else happens (DMA to
>> 	other piece of memory? Hard disk load glitching powre
>> 	supply?), memtest will not see the problem.
>
> These are not RAM faults.  The very last thing you want is evidence that 
> you've got a faulty piece of RAM when the fault is actually a hard disk 
> glitch!

No, it may be power supply leading to RAM problems. Yes, I want to
detect that.
								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/