Re: 4level page tables architecture porting

[Andi Kleen <ak@suse.de>]

On Fri, Oct 15, 2004 at 07:06:44PM +0100, David Woodhouse wrote:
> On Fri, 2004-10-15 at 17:21 +0200, Andi Kleen wrote:
> > ftp://ftp.suse.com/pub/people/ak/4level/4level-2.6.9rc4-2.gz
> > 
> > now compiles and boots on x86-64, i386, ia64. alpha, ppc64, ppc compile too,
> > but missing hardware I'm still waiting for testers for that.
> 
> ppc64 fails thus. Sorry, I'd be more helpful but I'm a little busy
> trying to work out why some ppc64 machines also die on startup because
> some of the initrd pages seem to be marked PG_slab by the time they get
> freed.

Thanks. It looks like the TASK_SIZE there is not a multiple of PGDIR_MASK.

Does it work with this patch?


diff -u linux-2.6.9rc4-4level/mm/mmap.c-Y linux-2.6.9rc4-4level/mm/mmap.c
--- linux-2.6.9rc4-4level/mm/mmap.c-Y	2004-10-12 15:31:28.000000000 +0200
+++ linux-2.6.9rc4-4level/mm/mmap.c	2004-10-15 21:21:04.000000000 +0200
@@ -1843,7 +1843,8 @@
 					~0UL, &nr_accounted, NULL);
 	vm_unacct_memory(nr_accounted);
 	BUG_ON(mm->map_count);	/* This is just debugging */
-	clear_page_range(tlb, FIRST_USER_PGD_NR * PGDIR_SIZE, TASK_SIZE);
+	clear_page_range(tlb, FIRST_USER_PGD_NR * PGDIR_SIZE, 
+			 (TASK_SIZE + PGDIR_SIZE - 1) & ~(PGDIR_SIZE - 1));
 	tlb_finish_mmu(tlb, 0, MM_VM_SIZE(mm));
 
 	vma = mm->mmap;


-Andi