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From: Parag Warudkar <parag.lkml@gmail.com>
To: Josh Triplett <josh@joshtriplett.org>
Cc: Andy Lutomirski <luto@amacapital.net>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-acpi@vger.kernel.org
Subject: Re: BGRT Pointer in System RAM
Date: Mon, 15 Jul 2013 20:00:39 -0400	[thread overview]
Message-ID: <CAOULuOYySYf=Qv973Wx+DZMYKok8uu=Nosw7-3ajNvcrNEspPA@mail.gmail.com> (raw)
In-Reply-To: <CAOULuOY=F5H_=Q1BcbrBxTAj9_9tXvOnm+KAtAksfDw2ei3hVw@mail.gmail.com>

On Mon, Jul 15, 2013 at 7:56 PM, Parag Warudkar <parag.lkml@gmail.com> wrote:
> On Mon, Jul 15, 2013 at 7:04 PM, Josh Triplett <josh@joshtriplett.org> wrote:
>
>> We do need to handle the case of a valid pointer into memory that e820
>> calls system RAM, as well as the case of a valid pointer into memory
>> reserved for the BIOS or similar, but not the case of an invalid
>> pointer.
>
> Would that be as simple as
>
>                      page_is_ram(

Damn shortcuts -
                        virt_addr = phys_to_virt(image->base_address);
                        if(page_is_ram(virt_to_page(virt_addr))) {
                            //direct read from virt addr
                        }

Would that suffice for the System RAM case or some other MM trickery
is involved?

Thanks,
Parag

      reply	other threads:[~2013-07-16  0:00 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-14 19:07 BGRT Pointer in System RAM Parag Warudkar
2013-07-15 20:28 ` Andy Lutomirski
2013-07-15 23:04   ` Josh Triplett
2013-07-15 23:08     ` Andy Lutomirski
2013-07-15 23:20       ` Josh Triplett
2013-07-15 23:24         ` Andy Lutomirski
2013-07-16 21:15           ` Andy Lutomirski
2013-07-15 23:56     ` Parag Warudkar
2013-07-16  0:00       ` Parag Warudkar [this message]

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