The patch titled
Subject: mm-make-alloc_contig_range-work-at-pageblock-granularity-fix
has been added to the -mm mm-unstable branch. Its filename is
mm-make-alloc_contig_range-work-at-pageblock-granularity-fix.patch
This patch should soon appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Zi Yan <ziy@xxxxxxxxxx>
Subject: mm-make-alloc_contig_range-work-at-pageblock-granularity-fix
Fix deadlock/crash at https://lore.kernel.org/linux-mm/20220426201855.GA1014@qian/
Link: https://lkml.kernel.org/r/23A7297E-6C84-4138-A9FE-3598234004E6@xxxxxxxxxx
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
Reported-by: Qian Cai <quic_qiancai@xxxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Eric Ren <renzhengeek@xxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_isolation.c | 89 +++++++++++++++++++++++-------------------
1 file changed, 49 insertions(+), 40 deletions(-)
--- a/mm/page_isolation.c~mm-make-alloc_contig_range-work-at-pageblock-granularity-fix
+++ a/mm/page_isolation.c
@@ -367,58 +367,67 @@ static int isolate_single_pageblock(unsi
}
/*
* migrate compound pages then let the free page handling code
- * above do the rest. If migration is not enabled, just fail.
+ * above do the rest. If migration is not possible, just fail.
*/
- if (PageHuge(page) || PageTransCompound(page)) {
-#if defined CONFIG_COMPACTION || defined CONFIG_CMA
+ if (PageCompound(page)) {
unsigned long nr_pages = compound_nr(page);
- int order = compound_order(page);
struct page *head = compound_head(page);
unsigned long head_pfn = page_to_pfn(head);
- int ret;
- struct compact_control cc = {
- .nr_migratepages = 0,
- .order = -1,
- .zone = page_zone(pfn_to_page(head_pfn)),
- .mode = MIGRATE_SYNC,
- .ignore_skip_hint = true,
- .no_set_skip_hint = true,
- .gfp_mask = gfp_flags,
- .alloc_contig = true,
- };
- INIT_LIST_HEAD(&cc.migratepages);
if (head_pfn + nr_pages < boundary_pfn) {
- pfn += nr_pages;
+ pfn = head_pfn + nr_pages;
continue;
}
-
- ret = __alloc_contig_migrate_range(&cc, head_pfn,
- head_pfn + nr_pages);
-
- if (ret)
- goto failed;
+#if defined CONFIG_COMPACTION || defined CONFIG_CMA
/*
- * reset pfn, let the free page handling code above
- * split the free page to the right migratetype list.
- *
- * head_pfn is not used here as a hugetlb page order
- * can be bigger than MAX_ORDER-1, but after it is
- * freed, the free page order is not. Use pfn within
- * the range to find the head of the free page and
- * reset order to 0 if a hugetlb page with
- * >MAX_ORDER-1 order is encountered.
+ * hugetlb, lru compound (THP), and movable compound pages
+ * can be migrated. Otherwise, fail the isolation.
*/
- if (order > MAX_ORDER-1)
+ if (PageHuge(page) || PageLRU(page) || __PageMovable(page)) {
+ int order;
+ unsigned long outer_pfn;
+ int ret;
+ struct compact_control cc = {
+ .nr_migratepages = 0,
+ .order = -1,
+ .zone = page_zone(pfn_to_page(head_pfn)),
+ .mode = MIGRATE_SYNC,
+ .ignore_skip_hint = true,
+ .no_set_skip_hint = true,
+ .gfp_mask = gfp_flags,
+ .alloc_contig = true,
+ };
+ INIT_LIST_HEAD(&cc.migratepages);
+
+ ret = __alloc_contig_migrate_range(&cc, head_pfn,
+ head_pfn + nr_pages);
+
+ if (ret)
+ goto failed;
+ /*
+ * reset pfn to the head of the free page, so
+ * that the free page handling code above can split
+ * the free page to the right migratetype list.
+ *
+ * head_pfn is not used here as a hugetlb page order
+ * can be bigger than MAX_ORDER-1, but after it is
+ * freed, the free page order is not. Use pfn within
+ * the range to find the head of the free page.
+ */
order = 0;
- while (!PageBuddy(pfn_to_page(pfn))) {
- order++;
- pfn &= ~0UL << order;
- }
- continue;
-#else
- goto failed;
+ outer_pfn = pfn;
+ while (!PageBuddy(pfn_to_page(outer_pfn))) {
+ if (++order >= MAX_ORDER) {
+ outer_pfn = pfn;
+ break;
+ }
+ outer_pfn &= ~0UL << order;
+ }
+ pfn = outer_pfn;
+ continue;
+ } else
#endif
+ goto failed;
}
pfn++;
_
Patches currently in -mm which might be from ziy@xxxxxxxxxx are
mm-page_isolation-move-has_unmovable_pages-to-mm-page_isolationc.patch
mm-page_isolation-check-specified-range-for-unmovable-pages.patch
mm-make-alloc_contig_range-work-at-pageblock-granularity.patch
mm-make-alloc_contig_range-work-at-pageblock-granularity-fix.patch
mm-page_isolation-enable-arbitrary-range-page-isolation.patch
mm-cma-use-pageblock_order-as-the-single-alignment.patch
drivers-virtio_mem-use-pageblock-size-as-the-minimum-virtio_mem-size.patch
