[merged mm-stable] mm-kmemleak-stop-the-per-cpu-and-struct-page-scans-early-too.patch removed from -mm tree

[merged mm-stable] mm-kmemleak-stop-the-per-cpu-and-struct-page-scans-early-too.patch removed from -mm tree

[Andrew Morton]

The quilt patch titled
     Subject: mm/kmemleak: stop the per-cpu and struct page scans early too
has been removed from the -mm tree.  Its filename was
     mm-kmemleak-stop-the-per-cpu-and-struct-page-scans-early-too.patch

This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

------------------------------------------------------
From: Breno Leitao <leitao@debian.org>
Subject: mm/kmemleak: stop the per-cpu and struct page scans early too
Date: Mon, 15 Jun 2026 10:49:08 -0700

The per-cpu and struct page scan loops have no reschedule-stop check of
their own: once a scan is interrupted they keep calling scan_block() for
every remaining block, which scans nothing useful.

Propagate scan_block()'s interrupted status through scan_large_block() and
break both loops as soon as it is set.

Link: https://lore.kernel.org/20260615-kmemleak-stack-resched-v3-3-acecd7d7fd92@debian.org
Signed-off-by: Breno Leitao <leitao@debian.org>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Qian Cai <cai@lca.pw>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kmemleak.c |   23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

--- a/mm/kmemleak.c~mm-kmemleak-stop-the-per-cpu-and-struct-page-scans-early-too
+++ a/mm/kmemleak.c
@@ -1559,18 +1559,22 @@ static int scan_block(void *_start, void
 
 /*
  * Scan a large memory block in MAX_SCAN_SIZE chunks to reduce the latency.
+ * Return non-zero if the scan was interrupted.
  */
 #ifdef CONFIG_SMP
-static void scan_large_block(void *start, void *end)
+static int scan_large_block(void *start, void *end)
 {
 	void *next;
 
 	while (start < end) {
 		next = min(start + MAX_SCAN_SIZE, end);
-		scan_block(start, next, NULL);
+		if (scan_block(start, next, NULL))
+			return 1;
 		start = next;
 		cond_resched();
 	}
+
+	return 0;
 }
 #endif
 
@@ -1890,9 +1894,11 @@ static void kmemleak_scan(void)
 
 #ifdef CONFIG_SMP
 	/* per-cpu sections scanning */
-	for_each_possible_cpu(i)
-		scan_large_block(__per_cpu_start + per_cpu_offset(i),
-				 __per_cpu_end + per_cpu_offset(i));
+	for_each_possible_cpu(i) {
+		if (scan_large_block(__per_cpu_start + per_cpu_offset(i),
+				     __per_cpu_end + per_cpu_offset(i)))
+			break;
+	}
 #endif
 
 	/*
@@ -1903,6 +1909,7 @@ static void kmemleak_scan(void)
 		unsigned long start_pfn = zone->zone_start_pfn;
 		unsigned long end_pfn = zone_end_pfn(zone);
 		unsigned long pfn;
+		int stop = 0;
 
 		for (pfn = start_pfn; pfn < end_pfn; pfn++) {
 			struct page *page = pfn_to_online_page(pfn);
@@ -1919,8 +1926,12 @@ static void kmemleak_scan(void)
 			/* only scan if page is in use */
 			if (page_count(page) == 0)
 				continue;
-			scan_block(page, page + 1, NULL);
+			stop = scan_block(page, page + 1, NULL);
+			if (stop)
+				break;
 		}
+		if (stop)
+			break;
 	}
 	put_online_mems();
 
_

Patches currently in -mm which might be from leitao@debian.org are

mm-memory-failure-drop-dead-error_states-entry-for-reserved-pages.patch
mm-memory-failure-surface-unhandlable-kernel-pages-as-enotrecoverable.patch
mm-memory-failure-report-mf_msg_kernel-for-unrecoverable-kernel-pages.patch
mm-memory-failure-add-panic-option-for-unrecoverable-pages.patch
documentation-document-panic_on_unrecoverable_memory_failure-sysctl.patch
radix-tree-fix-kmemleak-false-positives-on-tree-head-reassignment.patch
mm-kmemleak-report-leaks-only-after-n-consecutive-unreferenced-scans.patch
mm-kmemleak-factor-leak-confirmation-into-a-helper.patch
selftests-mm-test-kmemleaks-n-consecutive-scan-leak-confirmation.patch
mm-kmemleak-report-rcu-tasks-quiescent-states-during-the-scan.patch
mm-migrate-report-rcu-tasks-quiescent-states-in-migrate_pages_batch.patch