Re: [kbuild] [linux-next:master 7884/8197] mm/page_alloc.c:3813 rmqueue_pcplist() warn: inconsistent returns 'flags'.

[Mel Gorman <mgorman@suse.de>]

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On Thu, Jul 07, 2022 at 09:44:03AM +0300, Dan Carpenter wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git  master
> head:   088b9c375534d905a4d337c78db3b3bfbb52c4a0
> commit: fdd1b94629bb5592abf40d0c7a572b58e4c0cadc [7884/8197] mm/page_alloc: protect PCP lists with a spinlock
> config: i386-randconfig-m021
> compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
> 
> If you fix the issue, kindly add following tag where applicable
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> 

Thanks Dan,

I see Andrew has already merged a fix for this.

--8<--
mm-page_alloc-protect-pcp-lists-with-a-spinlock-fix

add missing local_unlock_irqrestore() on contention path

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 mm/page_alloc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 3b819c2720f8..66b902fef364 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3788,6 +3788,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone,
 	pcp_trylock_prepare(UP_flags);
 	if (!spin_trylock(&pcp->lock)) {
 		pcp_trylock_finish(UP_flags);
+		local_unlock_irqrestore(&pagesets.lock, flags);
 		return NULL;
 	}