From: "H. Peter Anvin" <hpa@zytor.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Ondrej Zary <linux@rainbow-software.org>,
Ingo Molnar <mingo@elte.hu>,
Yuhong Bao <yuhongbao_386@hotmail.com>,
linux-kernel@vger.kernel.org, gregkh@suse.de
Subject: Re: Windows side agrees that lowmem corruption is a problem too
Date: Tue, 08 Jun 2010 14:57:53 -0700 [thread overview]
Message-ID: <4C0EBCE1.2070609@zytor.com> (raw)
In-Reply-To: <20100608225656.7f645621@lxorguk.ukuu.org.uk>
On 06/08/2010 02:56 PM, Alan Cox wrote:
>>> I agree that dis-using <1M by default is probably the sanest option.
>>
>> But please limit it to newer systems only (DMI present && year > 200?). There
>> are many old machines running fine. Losing 1MB from 16MB is a bad thing.
>
> Losing the low 1MB is bad thing anyway for things like firmware flashing
> and other weird crap that needs low pages (floppy controllers etc).
>
> Losing 64K (but reporting corruption in it in a big scary way) is
> probably sensible for distributions, but its a config item so its policy
> so that wouldn't be a problem.
>
> It has to be painful to the vendors so they get complaints, reports and
> support call costs. Otherwise they won't have the correct incentives to
> fix their mess.
We have already functionally lost 64K on all existing machines... I
think the current blacklist covers 90% or more of all systems in
existence, and we keep filling in the few holes that remain.
Adding the remaining half-megabyte of RAM really shouldn't be done
unconditionally, but as I said it could plausibly be reserved for
ZONE_DMA only.
-hpa
next prev parent reply other threads:[~2010-06-08 21:58 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-08 18:28 Windows side agrees that lowmem corruption is a problem too Yuhong Bao
2010-06-08 19:06 ` H. Peter Anvin
2010-06-08 19:08 ` Ingo Molnar
2010-06-08 19:22 ` Ondrej Zary
2010-06-08 19:31 ` Yuhong Bao
2010-06-08 20:31 ` H. Peter Anvin
2010-06-08 20:49 ` Yuhong Bao
2010-06-11 1:15 ` Robert Hancock
2010-06-08 21:56 ` Alan Cox
2010-06-08 21:57 ` H. Peter Anvin [this message]
2010-06-09 1:08 ` Yuhong Bao
-- strict thread matches above, loose matches on Subject: below --
2010-06-08 18:12 Yuhong Bao
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