From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH 2/3] ARM: mm: add l2x0 physical address parameter to init
Date: Mon, 26 Sep 2011 15:51:04 +0100 [thread overview]
Message-ID: <20110926145104.GL22455@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1317047561-11020-3-git-send-email-lorenzo.pieralisi@arm.com>
On Mon, Sep 26, 2011 at 03:32:40PM +0100, Lorenzo Pieralisi wrote:
> This patch redefines the l2x0_init function, and it adds a
> parameter defining the L2 physical base address in preparation
> for L2 resume support. The device tree init code retrieves the
> physical address from the "reg" array and converts it to a
> physical address pointer.
I've no idea why many people have a really dire time understanding the
following basic fact. I keep seeing the same things: virtual addresses
as integers and physical addresses as pointers.
Virtual addresses are pointers.
Physical addresses are NOT pointers but integers.
Why? You CAN'T dereference a physical address when running in the virtual
address space (which is the space which the kernel runs in.)
Stop doing it.
next prev parent reply other threads:[~2011-09-26 14:51 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-26 14:32 [RFC PATCH 0/3] ARM: mm: add L2 suspend/resume support Lorenzo Pieralisi
2011-09-26 14:32 ` [RFC PATCH 1/3] ARM: mm: add outercache resume hook Lorenzo Pieralisi
2011-09-26 14:32 ` [RFC PATCH 2/3] ARM: mm: add l2x0 physical address parameter to init Lorenzo Pieralisi
2011-09-26 14:51 ` Russell King - ARM Linux [this message]
2011-09-26 16:02 ` Lorenzo Pieralisi
2011-09-26 14:32 ` [RFC PATCH 3/3] ARM: mm: add l2x0 suspend/resume support Lorenzo Pieralisi
2011-09-26 14:55 ` Russell King - ARM Linux
2011-09-26 16:27 ` Lorenzo Pieralisi
2011-09-26 15:06 ` Russell King - ARM Linux
2011-09-26 17:14 ` Lorenzo Pieralisi
2011-09-27 5:29 ` Santosh Shilimkar
2011-09-27 10:28 ` Lorenzo Pieralisi
2011-09-27 10:57 ` Santosh Shilimkar
2011-09-28 19:24 ` Russell King - ARM Linux
2011-09-29 5:38 ` Santosh Shilimkar
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