Commit a8a4b7ae authored Aug 14, 2020 by Baoquan He Committed by Linus Torvalds Aug 14, 2020

Revert "mm/vmstat.c: do not show lowmem reserve protection information of empty zone"



This reverts commit 26e7dead.

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.

Fixes: 26e7dead ("mm/vmstat.c: do not show lowmem reserve protection information of empty zone)"
Reported-by: Sonny Rao <sonnyrao@chromium.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>	[5.8.x]
Link: http://lkml.kernel.org/r/20200811075412.12872-1-bhe@redhat.com


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 9922c1de

mm/vmstat.c

+6 −6

Original line number	Diff line number	Diff line
		@@ -1642,12 +1642,6 @@ static void zoneinfo_show_print(struct seq_file m, pg_data_t pgdat,
		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 seq_file m, pg_data_t pgdat,
		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));

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