From eefe68280c94adc352c583d3312d8cbc3b6e9ccd Mon Sep 17 00:00:00 2001 From: Juntong Deng <juntong.deng@outlook.com> Date: Thu, 15 Feb 2024 19:17:23 +0000 Subject: [PATCH] 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> --- Documentation/dev-tools/kasan.rst | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index 858c77fe7dc46..d56f298a9d7ca 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 ---------------------- -- GitLab