+ mm-pagewalk-make-error-checks-more-obvious-fix.patch added to mm-unstable branch

+ mm-pagewalk-make-error-checks-more-obvious-fix.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: pagewalk: add back missing variable initializations
has been added to the -mm mm-unstable branch.  Its filename is
     mm-pagewalk-make-error-checks-more-obvious-fix.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-pagewalk-make-error-checks-more-obvious-fix.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: Rolf Eike Beer <eb@emlix.com>
Subject: mm: pagewalk: add back missing variable initializations
Date: Wed, 24 Aug 2022 13:00:11 +0200

These initializations accidentially got lost during refactoring.

The first one can't actually be used without initialization, because
walk_p4d_range() is only called when one of the 4 callbacks is set, but relying
on this seems fragile.

Link: https://lkml.kernel.org/r/2123960.ggj6I0NvhH@mobilepool36.emlix.com
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

--- a/mm/pagewalk.c~mm-pagewalk-make-error-checks-more-obvious-fix
+++ a/mm/pagewalk.c
@@ -225,7 +225,7 @@ static int walk_p4d_range(pgd_t *pgd, un
 
 	p4d = p4d_offset(pgd, addr);
 	do {
-		int err;
+		int err = 0;
 
 		next = p4d_addr_end(addr, end);
 		if (p4d_none_or_clear_bad(p4d)) {
_

Patches currently in -mm which might be from eb@emlix.com are

mm-pagewalk-make-error-checks-more-obvious.patch
mm-pagewalk-make-error-checks-more-obvious-fix.patch
mm-pagewalk-make-error-checks-more-obvious-fix-2.patch
mm-pagewalk-dont-check-vma-in-walk_page_range_novma.patch
mm-pagewalk-fix-documentation-of-pte-hole-handling.patch
mm-pagewalk-add-api-documentation-for-walk_page_range_novma.patch
mm-pagewalk-allow-walk_page_range_novma-without-mm.patch
mm-pagewalk-move-variables-to-more-local-scope-tweak-loops.patch
mm-pagewalk-move-variables-to-more-local-scope-tweak-loops-fix.patch
mm-pagewalk-add-back-missing-variable-initializations.patch