On 1/17/22 15:27, Chen Wandun wrote:
> This reverts commit 075782149abff45ee22f27315eced44d02b96779.
>
> commit 075782149abf ("mm/page_isolation: unset migratetype directly for
That's an old -next commit id, it went to mainline as 721fb891ad0b
("mm/page_isolation: unset migratetype directly for non Buddy page")
> non Buddy page") will result memory that should in buddy disappear by
> mistake. move_freepages_block move all pages in pageblock instead of
> pages indicated by input parameter, so if input pages is not in buddy
> but other pages in pageblock is in buddy, it will result in page out of
> control.
>
> Reported-by: "kernelci.org bot" <bot@xxxxxxxxxxxx>
> Signed-off-by: Chen Wandun <chenwandun@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
#regzbot ^introduced: 721fb891ad0b
There should better be also:
Fixes: 721fb891ad0b ("mm/page_isolation: unset migratetype directly for non
Buddy page")
Especially as that commit had a (inadequate, IMHO, for an optimization)
Fixes: tag and could end up being backported somewhere without the followup
fix/revert.
> ---
> mm/page_isolation.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/page_isolation.c b/mm/page_isolation.c
> index 6a0ddda6b3c5..f67c4c70f17f 100644
> --- a/mm/page_isolation.c
> +++ b/mm/page_isolation.c
> @@ -115,7 +115,7 @@ static void unset_migratetype_isolate(struct page *page, unsigned migratetype)
> * onlining - just onlined memory won't immediately be considered for
> * allocation.
> */
> - if (!isolated_page && PageBuddy(page)) {
> + if (!isolated_page) {
> nr_pages = move_freepages_block(zone, page, migratetype, NULL);
> __mod_zone_freepage_state(zone, nr_pages, migratetype);
> }
