Re: [PATCH v2] kasan: Add documentation for CONFIG_KASAN_EXTRA_INFO

[Andrey Konovalov]

On Thu, Feb 15, 2024 at 8:17 PM Juntong Deng <juntong.deng@xxxxxxxxxxx> wrote:
>
> This patch adds CONFIG_KASAN_EXTRA_INFO introduction information to
> KASAN documentation.
>
> Signed-off-by: Juntong Deng <juntong.deng@xxxxxxxxxxx>
> ---
> V1 -> V2: Fix run-on sentence.
>
>  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 a5a6dbe9029f..d7de44f5339d 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
>  ----------------------
>
> --
> 2.39.2
>

Reviewed-by: Andrey Konovalov <andreyknvl@xxxxxxxxx>