Yes I will do this before the end of the week.


Tom

-----Original Message-----
From: Maxim Uvarov [mailto:maxim.uvarov@oracle.com] 
Sent: Wednesday, January 25, 2012 5:21 PM
To: Mingarelli, Thomas
Cc: Wim Van Sebroeck; Linus Torvalds; linux-kernel@vger.kernel.org; akpm@linux-foundation.org; stable@vger.kernel.org; dann frazier
Subject: Re: [PATCH] hpwdt: clean up set_memory_x call for 32 bit

Thomas, will you be able to test patch accoring to  Linus's nr_page note?

Maxim.

On 01/24/2012 01:05 PM, Mingarelli, Thomas wrote:

Yes I agree that Maxim's patch is correct. The original set_memory_x call for 64 bit was done correctly and the newer calls are wrong.

The 2 pages for the BIOS SD is a known value so it should be safe to use as is.



Tom
-----Original Message-----
From: Wim Van Sebroeck [mailto:wim@iguana.be]
Sent: Tuesday, January 24, 2012 2:38 PM
To: Linus Torvalds
Cc: Maxim Uvarov; linux-kernel@vger.kernel.org; akpm@linux-foundation.org; stable@vger.kernel.org; Mingarelli, Thomas; dann frazier
Subject: Re: [PATCH] hpwdt: clean up set_memory_x call for 32 bit

Hi Linus,

quoted

So I don't know who is supposed to be handling this (Wim?), but the
patch itself looks suspicious.

I asked Tom to look at Maxim's patch and see what it does. Tom was going to look at the patch and
I'm waiting on feedback from him first. (That's why I din't sent it upstream yet).

quoted

On Sun, Jan 15, 2012 at 8:02 PM, Maxim Uvarov[off-list ref]  wrote:

quoted

-       set_memory_x((unsigned long)bios32_entrypoint, (2 * PAGE_SIZE));
+       set_memory_x((unsigned long)bios32_entrypoint&  PAGE_MASK, 2);

If it wasn't page-aligned to begin with, then maybe it needs three pages now?

quoted

-                               set_memory_x((unsigned long)cru_rom_addr, cru_length);
+                               set_memory_x((unsigned long)cru_rom_addr&  PAGE_MASK, cru_length>>  PAGE_SHIFT);

Same here. If we align the start address down, we should fix up the
length. And should we not align the number of pages up?

In general, a "start/length" conversion to a "page/nr" model needs to be roughly

    len += start&  ~PAGE_MASK;
    start&= PAGE_MASK;
    nr_pages = (len + PAGE_SIZE - 1)>>  PAGE_SHIFT;

to do things right. But I don't know where those magic numbers come
from. Maybe the "2" is already due to the code possibly traversing a
page boundary, and has already been fixed up. Somebody who knows the
driver and the requirements should take a look at this.

Valid comments indeed. Tom please take Linus comments with you when you look at the patch.

Dan: I put you in Cc: also so that you can have a look at it also.

Kind regards,
Wim.