From: Roland Dreier <rdreier@cisco.com>
To: "Yinghai Lu" <yinghai@kernel.org>
Cc: "James Kirin" <james.kirin40@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: memory beyond4GB invisible to the system even though CONFIG_HIGHMEM64G=y
Date: Wed, 14 Jan 2009 08:14:35 -0800 [thread overview]
Message-ID: <ada63khkgpg.fsf@cisco.com> (raw)
In-Reply-To: <86802c440901132207l433227d9nf149506012a5721e@mail.gmail.com> (Yinghai Lu's message of "Tue, 13 Jan 2009 22:07:26 -0800")
> please do
> 1. boot linux with "disable_mtrr_trim" in grub.conf etc
> 2. after booting input:
> echo "base=0x100000000 size=0x20000000 type=write-back" >/proc/mtrr
Is there any way we can have the kernel do this automatically if there
are any free mtrr slots? I would guess this type of BIOS bug is pretty
common (desktop boards not validated with > 4GB of RAM), and having the
kernel throw away 4GB of memory unless the user does some fancy
scripting is not very friendly (not to mention the fact that things are
likely to be very slow until the mtrr fixup script runs).
- R.
next prev parent reply other threads:[~2009-01-14 16:14 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-14 1:46 memory beyond4GB invisible to the system even though CONFIG_HIGHMEM64G=y James Kirin
2009-01-14 2:22 ` Roland Dreier
2009-01-14 3:10 ` James Kirin
2009-01-14 6:07 ` Yinghai Lu
2009-01-14 16:14 ` Roland Dreier [this message]
2009-01-14 18:16 ` Yinghai Lu
2009-01-15 19:50 ` James Kirin
2009-01-15 20:35 ` James Kirin
2009-01-15 20:45 ` Yinghai Lu
2009-01-15 20:51 ` Yinghai Lu
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