From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Fri, 24 Nov 2017 10:14:24 +0000 (+0100)
Subject: 4.4-stable patches
X-Git-Tag: v4.4.102~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=79c8dc70226f3cd65c3824afad13ef56e4ea646d;p=thirdparty%2Fkernel%2Fstable-queue.git

4.4-stable patches

added patches:
	mm-hwpoison-fixup-mm-check-the-return-value-of-lookup_page_ext-for-all-call-sites.patch
---

diff --git a/queue-4.4/mm-hwpoison-fixup-mm-check-the-return-value-of-lookup_page_ext-for-all-call-sites.patch b/queue-4.4/mm-hwpoison-fixup-mm-check-the-return-value-of-lookup_page_ext-for-all-call-sites.patch
new file mode 100644
index 00000000000..ca8173e073d
--- /dev/null
+++ b/queue-4.4/mm-hwpoison-fixup-mm-check-the-return-value-of-lookup_page_ext-for-all-call-sites.patch
@@ -0,0 +1,53 @@
+From foo@baz Fri Nov 24 11:13:07 CET 2017
+Date: Fri, 24 Nov 2017 11:13:07 +0100
+To: Greg KH <gregkh@linuxfoundation.org>
+From: Michal Hocko <mhocko@suse.com>
+Subject: mm, hwpoison: fixup "mm: check the return value of lookup_page_ext for all call sites"
+
+From: Michal Hocko <mhocko@suse.com>
+
+
+Backport of the upstream commit f86e4271978b ("mm: check the return
+value of lookup_page_ext for all call sites") is wrong for hwpoison
+pages. I have accidentally negated the condition for bailout. This
+basically disables hwpoison pages tracking while the code still
+might crash on unusual configurations when struct pages do not have
+page_ext allocated. The fix is trivial to invert the condition.
+
+Reported-by: Jiri Slaby <jslaby@suse.cz>
+Signed-off-by: Michal Hocko <mhocko@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ mm/debug-pagealloc.c |    6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+--- a/mm/debug-pagealloc.c
++++ b/mm/debug-pagealloc.c
+@@ -34,7 +34,7 @@ static inline void set_page_poison(struc
+ 	struct page_ext *page_ext;
+ 
+ 	page_ext = lookup_page_ext(page);
+-	if (page_ext)
++	if (!page_ext)
+ 		return;
+ 	__set_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
+ }
+@@ -44,7 +44,7 @@ static inline void clear_page_poison(str
+ 	struct page_ext *page_ext;
+ 
+ 	page_ext = lookup_page_ext(page);
+-	if (page_ext)
++	if (!page_ext)
+ 		return;
+ 	__clear_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
+ }
+@@ -54,7 +54,7 @@ static inline bool page_poison(struct pa
+ 	struct page_ext *page_ext;
+ 
+ 	page_ext = lookup_page_ext(page);
+-	if (page_ext)
++	if (!page_ext)
+ 		return false;
+ 	return test_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
+ }
diff --git a/queue-4.4/series b/queue-4.4/series
new file mode 100644
index 00000000000..c404cbb7611
--- /dev/null
+++ b/queue-4.4/series
@@ -0,0 +1 @@
+mm-hwpoison-fixup-mm-check-the-return-value-of-lookup_page_ext-for-all-call-sites.patch