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To: Laurent Dufour <ldufour@linux.vnet.ibm.com>
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Subject: Re: [PATCH v9 06/24] mm: make pte_unmap_same compatible with SPF
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On Wed, 28 Mar 2018, Laurent Dufour wrote:

> >> @@ -2913,7 +2921,8 @@ int do_swap_page(struct vm_fault *vmf)
> >>  	int exclusive = 0;
> >>  	int ret = 0;
> > 
> > Initialization is now unneeded.
> 
> I'm sorry, what "initialization" are you talking about here ?
> 

The initialization of the ret variable.

@@ -2913,7 +2921,8 @@ int do_swap_page(struct vm_fault *vmf)
 	int exclusive = 0;
 	int ret = 0;
 
-	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
+	ret = pte_unmap_same(vmf);
+	if (ret)
 		goto out;
 
 	entry = pte_to_swp_entry(vmf->orig_pte);

"ret" is immediately set to the return value of pte_unmap_same(), so there 
is no need to initialize it to 0.