From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Sat, 3 Aug 2013 15:09:48 +0100
Subject: [PATCH v2 4/6] ARM: mm: LPAE: Correct virt_to_phys patching
 for 64 bit physical addresses
In-Reply-To: <20130803140544.GB23006@n2100.arm.linux.org.uk>
References: <1375289086-5315-1-git-send-email-santosh.shilimkar@ti.com>
 <1375289086-5315-5-git-send-email-santosh.shilimkar@ti.com>
 <alpine.LFD.2.03.1308022156120.14472@syhkavp.arg> <51FCFBE1.5090000@ti.com>
 <20130803140544.GB23006@n2100.arm.linux.org.uk>
Message-ID: <20130803140948.GC23006@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Sat, Aug 03, 2013 at 03:05:44PM +0100, Russell King - ARM Linux wrote:
> On Sat, Aug 03, 2013 at 06:17:29PM +0530, Sricharan R wrote:
> >   I started with this kind of augmenting with the immediate operand
> >   while starting V2. But the problem was, we do the runtime patching twice.
> 
> It might be much better to do this only once, and instead of having the
> early code overwrite the page table in use, create a new page table with
> all the correct page table entries in and switch to that.

Note: we still need to do a certain amount of modification of the existing
page table so that we _can_ perform such a switch on all our CPUs - that
is, ensuring that the region for flushing the CPU caches on processors
which need it is properly mapped.