Re: [PATCH 03/13] powerpc: Fix booke hugetlb preload code for PPC_MM_SLICES and 64-bit

On Mon, 2011-10-10 at 15:50 -0500, Becky Bruce wrote:

 .../...

 #ifdef CONFIG_PPC_MM_SLICES
-	psize = mmu_get_tsize(get_slice_psize(mm, ea));
-	tsize = mmu_get_psize(psize);
+	psize = get_slice_psize(mm, ea);
+	tsize = mmu_get_tsize(psize);
 	shift = mmu_psize_defs[psize].shift;
 #else
-	vma = find_vma(mm, ea);
-	psize = vma_mmu_pagesize(vma);	/* returns actual size in bytes */
-	asm (PPC_CNTLZL "%0,%1" : "=r" (lz) : "r" (psize));
-	shift = 31 - lz;
-	tsize = 21 - lz;
+	psize = vma_mmu_pagesize(find_vma(mm, ea));
+	shift = __ilog2(psize);
+	tsize = shift - 10;
 #endif

Now, I know it was already there and you are just moving it around in
this patch but come on ... find_vma() here ? Really ? And with no result
checking nor boundary checking (remember it can return a vma that
doesn't enclose the address etc....). Now I know in this specific case
it -should- be safe but still...

Now, the caller is just doing:
 
	book3e_hugetlb_preload(vma->vm_mm, address, *ptep);

So why not just change the prototype and pass the vma down instead ?

Cheers,
Ben.