Re: [PATCH v2] lockdep: Add header and footer to surround warning reports

[Waiman Long <llong@redhat.com>]

On 12/16/25 7:31 PM, Tzung-Bi Shih wrote:
> On Tue, Dec 16, 2025 at 11:20:45AM -0500, Waiman Long wrote:
>> On 12/15/25 2:26 AM, Tzung-Bi Shih wrote:
>>> Add header and footer to improve log parsing and automated analysis.
>>> This makes lockdep output easier to interpret.
>>>
>>> Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
>>> ---
>>> v2:
>>> - asm/bugs.h -> linux/bug.h.
>>>
>>> v1: https://lore.kernel.org/all/20251114062730.1828416-1-tzungbi@kernel.org/
>>>
>>>    kernel/locking/lockdep.c | 34 ++++++++++++++++++++++++++++++++++
>>>    1 file changed, 34 insertions(+)
>>>
>>> diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
>>> index 2d4c5bab5af8..adbc44c3808d 100644
>>> --- a/kernel/locking/lockdep.c
>>> +++ b/kernel/locking/lockdep.c
>>> @@ -58,6 +58,7 @@
>>>    #include <linux/context_tracking.h>
>>>    #include <linux/console.h>
>>>    #include <linux/kasan.h>
>>> +#include <linux/bug.h>
>>>    #include <asm/sections.h>
>>> @@ -110,6 +111,11 @@ static __init int kernel_lockdep_sysctls_init(void)
>>>    late_initcall(kernel_lockdep_sysctls_init);
>>>    #endif /* CONFIG_SYSCTL */
>>> +static void print_footer(void)
>>> +{
>>> +	pr_warn("---[ end trace %016llx ]---\n", 0ULL);
>> What is the purpose of putting 16 '0' in this "end trace" line? Is it
>> related to how your parsing script works?
> Mostly wanted to align to print_oops_end_marker() in kernel/panic.c.  Before
> e83a4472bf9f ("panic: remove oops_id"), it was an oops ID.  My parsing script
> doesn't rely on the 16 '0's but existing parsers might.
>
> I have no strong opinion.  Should we just remove the 16 '0's here?

These are warning messages, not panic. So I would prefer not to have 
them if they serve no useful purpose and can cause confusion.

Cheers,
Longman

>