vsock/test: Add README blurb about kmemleak usage

Document the suggested use of kmemleak for memory leak detection.

Suggested-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20241219-test-vsock-leaks-v4-3-a416e554d9d7@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/tools/testing/vsock/README b/tools/testing/vsock/README
index 84ee217ba8eed8d18eebecc4dc81088934f76d8f..680ce666ceb56db986c8ad078573d774e6fecf18 100644 (file)
--- a/tools/testing/vsock/README
+++ b/tools/testing/vsock/README
@@ -36,6 +36,21 @@ Invoke test binaries in both directions as follows:
                        --control-port=1234 \
                        --peer-cid=3
 
+Some tests are designed to produce kernel memory leaks. Leaks detection,
+however, is deferred to Kernel Memory Leak Detector. It is recommended to enable
+kmemleak (CONFIG_DEBUG_KMEMLEAK=y) and explicitly trigger a scan after each test
+suite run, e.g.
+
+  # echo clear > /sys/kernel/debug/kmemleak
+  # $TEST_BINARY ...
+  # echo "wait for any grace periods" && sleep 2
+  # echo scan > /sys/kernel/debug/kmemleak
+  # echo "wait for kmemleak" && sleep 5
+  # echo scan > /sys/kernel/debug/kmemleak
+  # cat /sys/kernel/debug/kmemleak
+
+For more information see Documentation/dev-tools/kmemleak.rst.
+
 vsock_perf utility
 -------------------
 'vsock_perf' is a simple tool to measure vsock performance. It works in