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
prev parent 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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