This is a note to let you know that I've just added the patch titled

    powerpc: Fix device tree claim code

to the 2.6.32-longterm tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/longterm/longterm-queue-2.6.32.git;a=summary

The filename of the patch is:
     powerpc-fix-device-tree-claim-code.patch
and it can be found in the queue-2.6.32 subdirectory.

If you, or anyone else, feels it should not be added to the 2.6.32 longterm 
tree,
please let <sta...@kernel.org> know about it.


>From 966728dd88b4026ec58fee169ccceaeaf56ef120 Mon Sep 17 00:00:00 2001
From: Anton Blanchard <an...@samba.org>
Date: Mon, 25 Jul 2011 20:47:07 +0000
Subject: powerpc: Fix device tree claim code

From: Anton Blanchard <an...@samba.org>

commit 966728dd88b4026ec58fee169ccceaeaf56ef120 upstream.

I have a box that fails in OF during boot with:

DEFAULT CATCH!, exception-handler=fff00400
at   %SRR0: 49424d2c4c6f6768   %SRR1: 800000004000b002

ie "IBM,Logh". OF got corrupted with a device tree string.

Looking at make_room and alloc_up, we claim the first chunk (1 MB)
but we never claim any more. mem_end is always set to alloc_top
which is the top of our available address space, guaranteeing we will
never call alloc_up and claim more memory.

Also alloc_up wasn't setting alloc_bottom to the bottom of the
available address space.

This doesn't help the box to boot, but we at least fail with
an obvious error. We could relocate the device tree in a future
patch.

Signed-off-by: Anton Blanchard <an...@samba.org>
Signed-off-by: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gre...@suse.de>

---
 arch/powerpc/kernel/prom_init.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c
@@ -890,7 +890,7 @@ static unsigned long __init alloc_up(uns
        }
        if (addr == 0)
                return 0;
-       RELOC(alloc_bottom) = addr;
+       RELOC(alloc_bottom) = addr + size;
 
        prom_debug(" -> %x\n", addr);
        prom_debug("  alloc_bottom : %x\n", RELOC(alloc_bottom));
@@ -1704,7 +1704,7 @@ static void __init *make_room(unsigned l
                chunk = alloc_up(room, 0);
                if (chunk == 0)
                        prom_panic("No memory for flatten_device_tree (claim 
failed)");
-               *mem_end = RELOC(alloc_top);
+               *mem_end = chunk + room;
        }
 
        ret = (void *)*mem_start;
@@ -1923,7 +1923,7 @@ static void __init flatten_device_tree(v
        mem_start = (unsigned long)alloc_up(room, PAGE_SIZE);
        if (mem_start == 0)
                prom_panic("Can't allocate initial device-tree chunk\n");
-       mem_end = RELOC(alloc_top);
+       mem_end = mem_start + room;
 
        /* Get root of tree */
        root = call_prom("peer", 1, 1, (phandle)0);


Patches currently in longterm-queue-2.6.32 which might be from an...@samba.org 
are

/home/gregkh/linux/longterm/longterm-queue-2.6.32/queue-2.6.32/powerpc-pseries-fix-kexec-on-machines-with-more-than-4tb-of-ram.patch
/home/gregkh/linux/longterm/longterm-queue-2.6.32/queue-2.6.32/powerpc-fix-device-tree-claim-code.patch

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