diff mbox series

[01/54] mm/page_idle.c: skip offline pages

Message ID 20200608044004.04xI8ALrc%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [01/54] mm/page_idle.c: skip offline pages | expand

Commit Message

Andrew Morton June 8, 2020, 4:40 a.m. UTC 
From: SeongJae Park <sjpark@amazon.de>
Subject: mm/page_idle.c: skip offline pages

'Idle page tracking' users can pass random pfn that might be mapped to an
offline page.  To avoid accessing such pages, this commit modifies the
'page_idle_get_page()' to use 'pfn_to_online_page()' instead of
'pfn_valid()' and 'pfn_to_page()' combination, so that the pfn mapped to
an offline page can be skipped.

Link: http://lkml.kernel.org/r/20200605092502.18018-2-sjpark@amazon.com
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_idle.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)
diff mbox series

Patch

--- a/mm/page_idle.c~mm-page_idlec-skip-offline-pages
+++ a/mm/page_idle.c
@@ -4,6 +4,7 @@ 
 #include <linux/fs.h>
 #include <linux/sysfs.h>
 #include <linux/kobject.h>
+#include <linux/memory_hotplug.h>
 #include <linux/mm.h>
 #include <linux/mmzone.h>
 #include <linux/pagemap.h>
@@ -30,13 +31,9 @@ 
  */
 static struct page *page_idle_get_page(unsigned long pfn)
 {
-	struct page *page;
+	struct page *page = pfn_to_online_page(pfn);
 	pg_data_t *pgdat;
 
-	if (!pfn_valid(pfn))
-		return NULL;
-
-	page = pfn_to_page(pfn);
 	if (!page || !PageLRU(page) ||
 	    !get_page_unless_zero(page))
 		return NULL;