[PATCH v2 2/3] Documentation: kmemleak: document the conditional min_unref_scans default

Breno Leitao <[email protected]> Fri, 31 Jul 2026 03:13:05 -0700
Newsgroups org.kernel.vger.workflows,org.kernel.vger.linux-doc,org.kernel.vger.linux-kernel,org.kernel.vger.linux-kselftest,org.kvack.linux-mm
Message-ID <[email protected]>
min_unref_scans now defaults to 2 when CONFIG_DEBUG_KMEMLEAK_AUTO_SCAN and
CONFIG_DEBUG_KMEMLEAK_VERBOSE are both enabled, but the documentation still
states that the default is unconditionally 1.

Signed-off-by: Breno Leitao <[email protected]>
---
 Documentation/dev-tools/kmemleak.rst | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/Documentation/dev-tools/kmemleak.rst b/Documentation/dev-tools/kmemleak.rst
index a8a83bc69ceb8..d1b690b171696 100644
--- a/Documentation/dev-tools/kmemleak.rst
+++ b/Documentation/dev-tools/kmemleak.rst
@@ -198,11 +198,13 @@ systems, because of pointers temporarily stored in CPU registers or
 stacks. Kmemleak defines MSECS_MIN_AGE (defaulting to 1000) representing
 the minimum age of an object to be reported as a memory leak.
 
-The ``min_unref_scans`` module parameter (default 1) requires an object to
-be seen unreferenced in that many consecutive scans before it is reported.
-Keeping it at 1 preserves the historical behaviour; higher values filter
-the transient false positives described above, at the cost of delaying
-genuine reports by up to that many scans. It can be set at boot with
+The ``min_unref_scans`` module parameter requires an object to be seen
+unreferenced in that many consecutive scans before it is reported. It
+defaults to 2 when CONFIG_DEBUG_KMEMLEAK_VERBOSE is enabled, where the
+periodic scan thread confirms a leak on its own, and to 1 otherwise. A
+value of 1 preserves the historical behaviour; higher values filter the
+transient false positives described above, at the cost of delaying genuine
+reports by up to that many scans. It can be set at boot with
 ``kmemleak.min_unref_scans=<n>`` or at run-time via
 ``/sys/module/kmemleak/parameters/min_unref_scans``.
 

-- 
2.53.0-Meta