On Mon, Mar 25, 2019 at 09:06:14PM +0500, Mikhail Gavrilov wrote:
> > }
> > -
> > - /* Leave no distance if no suitable block was reset */
> > - if (reset_migrate >= reset_free) {
> > - zone->compact_cached_migrate_pfn[0] = migrate_pfn;
> > - zone->compact_cached_migrate_pfn[1] = migrate_pfn;
> > - zone->compact_cached_free_pfn = free_pfn;
> > - }
> > }
> >
> > void reset_isolation_suitable(pg_data_t *pgdat)
> >
>
> Kernel panic are still occurs.
>
Ok, thanks.
Trying one last time before putting together a debugging patch to see
exactly what PFNs are triggering as I still have not reproduced this on a
local machine. This is another replacement that is based on the assumption
that it's the free_pfn at the end of the zone that is triggering the
warning and it happens to be the case the end of a zone is aligned. Sorry
for the frustration with this and for persisting.
diff --git a/mm/compaction.c b/mm/compaction.c
index f171a83707ce..b4930bf93c8a 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -242,6 +242,7 @@ __reset_isolation_pfn(struct zone *zone, unsigned long pfn, bool check_source,
bool check_target)
{
struct page *page = pfn_to_online_page(pfn);
+ struct page *block_page;
struct page *end_page;
unsigned long block_pfn;
@@ -267,20 +268,26 @@ __reset_isolation_pfn(struct zone *zone, unsigned long pfn, bool check_source,
get_pageblock_migratetype(page) != MIGRATE_MOVABLE)
return false;
+ /* Ensure the start of the pageblock or zone is online and valid */
+ block_pfn = pageblock_start_pfn(pfn);
+ block_page = pfn_to_online_page(max(block_pfn, zone->zone_start_pfn));
+ if (block_page) {
+ page = block_page;
+ pfn = block_pfn;
+ }
+
+ /* Ensure the end of the pageblock or zone is online and valid */
+ block_pfn += pageblock_nr_pages;
+ block_pfn = min(block_pfn, zone_end_pfn(zone) - 1);
+ end_page = pfn_to_online_page(block_pfn);
+ if (!end_page)
+ return false;
+
/*
* Only clear the hint if a sample indicates there is either a
* free page or an LRU page in the block. One or other condition
* is necessary for the block to be a migration source/target.
*/
- block_pfn = pageblock_start_pfn(pfn);
- pfn = max(block_pfn, zone->zone_start_pfn);
- page = pfn_to_page(pfn);
- if (zone != page_zone(page))
- return false;
- pfn = block_pfn + pageblock_nr_pages;
- pfn = min(pfn, zone_end_pfn(zone));
- end_page = pfn_to_page(pfn);
-
do {
if (pfn_valid_within(pfn)) {
if (check_source && PageLRU(page)) {
@@ -309,7 +316,7 @@ __reset_isolation_pfn(struct zone *zone, unsigned long pfn, bool check_source,
static void __reset_isolation_suitable(struct zone *zone)
{
unsigned long migrate_pfn = zone->zone_start_pfn;
- unsigned long free_pfn = zone_end_pfn(zone);
+ unsigned long free_pfn = zone_end_pfn(zone) - 1;
unsigned long reset_migrate = free_pfn;
unsigned long reset_free = migrate_pfn;
bool source_set = false;
--
Mel Gorman
SUSE Labs
