summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJuntong Deng <juntong.deng@outlook.com>2024-02-15 19:17:23 +0000
committerJonathan Corbet <corbet@lwn.net>2024-02-21 13:44:21 -0700
commiteefe68280c94adc352c583d3312d8cbc3b6e9ccd (patch)
treeef29533774d4611c7d86d8d9fb2b12b1be831e4b
parentd4f42b71e816b19dd44b373e1006ca64da75c192 (diff)
downloadlwn-eefe68280c94adc352c583d3312d8cbc3b6e9ccd.tar.gz
lwn-eefe68280c94adc352c583d3312d8cbc3b6e9ccd.zip
kasan: Add documentation for CONFIG_KASAN_EXTRA_INFO
This patch adds CONFIG_KASAN_EXTRA_INFO introduction information to KASAN documentation. Signed-off-by: Juntong Deng <juntong.deng@outlook.com> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Link: https://lore.kernel.org/r/AM6PR03MB5848C52B871DA67455F0B2F2994D2@AM6PR03MB5848.eurprd03.prod.outlook.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
-rw-r--r--Documentation/dev-tools/kasan.rst21
1 files changed, 21 insertions, 0 deletions
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst
index 858c77fe7dc4..d56f298a9d7c 100644
--- a/Documentation/dev-tools/kasan.rst
+++ b/Documentation/dev-tools/kasan.rst
@@ -277,6 +277,27 @@ traces point to places in code that interacted with the object but that are not
directly present in the bad access stack trace. Currently, this includes
call_rcu() and workqueue queuing.
+CONFIG_KASAN_EXTRA_INFO
+~~~~~~~~~~~~~~~~~~~~~~~
+
+Enabling CONFIG_KASAN_EXTRA_INFO allows KASAN to record and report more
+information. The extra information currently supported is the CPU number and
+timestamp at allocation and free. More information can help find the cause of
+the bug and correlate the error with other system events, at the cost of using
+extra memory to record more information (more cost details in the help text of
+CONFIG_KASAN_EXTRA_INFO).
+
+Here is the report with CONFIG_KASAN_EXTRA_INFO enabled (only the
+different parts are shown)::
+
+ ==================================================================
+ ...
+ Allocated by task 134 on cpu 5 at 229.133855s:
+ ...
+ Freed by task 136 on cpu 3 at 230.199335s:
+ ...
+ ==================================================================
+
Implementation details
----------------------