On 05.06.20 11:25, SeongJae Park wrote:
> From: SeongJae Park <sjpark@xxxxxxxxx>
>
> '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.
>
> Signed-off-by: SeongJae Park <sjpark@xxxxxxxxx>
> Reported-by: David Hildenbrand <david@xxxxxxxxxx>
> ---
> mm/page_idle.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/mm/page_idle.c b/mm/page_idle.c
> index 295512465065..057c61df12db 100644
> --- a/mm/page_idle.c
> +++ b/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;
>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
--
Thanks,
David / dhildenb
