+ mm-highmem-pass-a-pointer-to-virt_to_page.patch added to mm-unstable branch

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The patch titled
     Subject: mm/highmem: pass a pointer to virt_to_page()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-highmem-pass-a-pointer-to-virt_to_page.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-highmem-pass-a-pointer-to-virt_to_page.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Linus Walleij <linus.walleij@xxxxxxxxxx>
Subject: mm/highmem: pass a pointer to virt_to_page()
Date: Thu, 30 Jun 2022 10:41:21 +0200

Functions that work on a pointer to virtual memory such as virt_to_pfn()
and users of that function such as virt_to_page() are supposed to pass a
pointer to virtual memory, ideally a (void *) or other pointer.  However
since many architectures implement virt_to_pfn() as a macro, this function
becomes polymorphic and accepts both a (unsigned long) and a (void *).

If we instead implement a proper virt_to_pfn(void *addr) function the
following happens (occurred on arch/arm):

mm/highmem.c:153:29: warning: passing argument 1 of
  'virt_to_pfn' makes pointer from integer without a
  cast [-Wint-conversion]

We already have a proper void * pointer in the scope of this function
named "vaddr" so pass that instead.

Link: https://lkml.kernel.org/r/20220630084124.691207-3-linus.walleij@xxxxxxxxxx
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 mm/highmem.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/highmem.c~mm-highmem-pass-a-pointer-to-virt_to_page
+++ a/mm/highmem.c
@@ -150,7 +150,7 @@ struct page *__kmap_to_page(void *vaddr)
 		return pte_page(pkmap_page_table[i]);
 	}
 
-	return virt_to_page(addr);
+	return virt_to_page(vaddr);
 }
 EXPORT_SYMBOL(__kmap_to_page);
 
_

Patches currently in -mm which might be from linus.walleij@xxxxxxxxxx are

lib-test_free_pagesc-pass-a-pointer-to-virt_to_page.patch
mm-highmem-pass-a-pointer-to-virt_to_page.patch
mm-kfence-pass-a-pointer-to-virt_to_page.patch
mm-gup-pass-a-pointer-to-virt_to_page.patch
mm-nommu-pass-a-pointer-to-virt_to_page.patch




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