[merged] revert-mm-vmstatc-do-not-show-lowmem-reserve-protection-information-of-empty-zone.patch removed from -mm tree

[merged] revert-mm-vmstatc-do-not-show-lowmem-reserve-protection-information-of-empty-zone.patch removed from -mm tree

[akpm]

The patch titled
     Subject: Revert "mm/vmstat.c: do not show lowmem reserve protection information of empty zone"
has been removed from the -mm tree.  Its filename was
     revert-mm-vmstatc-do-not-show-lowmem-reserve-protection-information-of-empty-zone.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Baoquan He <bhe@redhat.com>
Subject: Revert "mm/vmstat.c: do not show lowmem reserve protection information of empty zone"

This reverts commit 26e7deadaae175.

Sonny reported that one of their tests started failing on the latest
kernel on their Chrome OS platform.  The root cause is that the above
commit removed the protection line of empty zone, while the parser used in
the test relies on the protection line to mark the end of each zone.

Let's revert it to avoid breaking userspace testing or applications.

Link: http://lkml.kernel.org/r/20200811075412.12872-1-bhe@redhat.com
Fixes: 26e7deadaae175 ("mm/vmstat.c: do not show lowmem reserve protection information of empty zone)"
Signed-off-by: Baoquan He <bhe@redhat.com>
Reported-by: Sonny Rao <sonnyrao@chromium.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>	[5.8.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmstat.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/mm/vmstat.c~revert-mm-vmstatc-do-not-show-lowmem-reserve-protection-information-of-empty-zone
+++ a/mm/vmstat.c
@@ -1642,12 +1642,6 @@ static void zoneinfo_show_print(struct s
 		   zone->present_pages,
 		   zone_managed_pages(zone));
 
-	/* If unpopulated, no other information is useful */
-	if (!populated_zone(zone)) {
-		seq_putc(m, '\n');
-		return;
-	}
-
 	seq_printf(m,
 		   "\n        protection: (%ld",
 		   zone->lowmem_reserve[0]);
@@ -1655,6 +1649,12 @@ static void zoneinfo_show_print(struct s
 		seq_printf(m, ", %ld", zone->lowmem_reserve[i]);
 	seq_putc(m, ')');
 
+	/* If unpopulated, no other information is useful */
+	if (!populated_zone(zone)) {
+		seq_putc(m, '\n');
+		return;
+	}
+
 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
 		seq_printf(m, "\n      %-12s %lu", zone_stat_name(i),
 			   zone_page_state(zone, i));
_

Patches currently in -mm which might be from bhe@redhat.com are