linux-kernel - Re: [RFC PATCH 2/2] clocksource: Use cpumask_first_but() in clocksource_verify_choose

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aEuw7ls9hieUv_Ox@yury>
Date: Fri, 13 Jun 2025 01:02:38 -0400
From: Yury Norov <yury.norov@...il.com>
To: I Hsin Cheng <richard120310@...il.com>
Cc: linux@...musvillemoes.dk, jstultz@...gle.com, tglx@...utronix.de,
	sboyd@...nel.org, linux-kernel@...r.kernel.org,
	eleanor15x@...il.com, visitorckw@...il.com, jserv@...s.ncku.edu.tw,
	skhan@...uxfoundation.org, linux-kernel-mentees@...ts.linux.dev
Subject: Re: [RFC PATCH 2/2] clocksource: Use cpumask_first_but() in
 clocksource_verify_choose_cpus()

I Hsin,

This exact change has already been submitted by me and is under review.

https://lore.kernel.org/all/20250604232550.40491-2-yury.norov@gmail.com/

I don't understand why are you undercutting my work, and moreover do it 
for the second time.

For the first time you submitted something that duplicates my another
patch from the exact same series. John Stultz has pointed that, so you're
surely aware.

https://lore.kernel.org/all/CANDhNCoJ_MmpEfyuL+JWav+NUfQDH3dm196JSE-Mv3QrPUzi3g@mail.gmail.com/

Kernel development process implies that one makes sure that his work
is unique and doesn't break someone else's development, at one's best
knowledge.

What you're doing not only breaks this rule. You're in fact trying to
get credit for the work that is done by someone else. This is the
definition of fraud.

I cannot make sure that any other patches from you are unique and
written by actually you. Therefore, I will not take your work anymore.

I encourage everyone else to be careful working with I Hsing Cheng
and check his patches for uniqueness, at minimum.  

NAKed-by: Yury Norov <yury.norov@...il.com>

Thanks,
Yury

On Fri, Jun 13, 2025 at 11:34:47AM +0800, I Hsin Cheng wrote:
> Utilize cpumask_first_but() helper instead of first using
> cpumask_first() and then cpumask_next(). The logic is the same here,
> using the new helper will make it more conscious.
> 
> Use bloat-o-meter to check the impact on code size, the result is the
> same, does not have positive impact nor negative impact.
> 
> $ ./scripts/bloat-o-meter vmlinux_old vmlinux_new
> add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0 (0)
> Function                                     old     new   delta
> Total: Before=22590709, After=22590709, chg +0.00%
> 
> Signed-off-by: I Hsin Cheng <richard120310@...il.com>
> ---
> Generally speaking, I think this is just a small tweak on the code,
> making it more readable. However, no benefit in code size or performance
> as the implementation behind the helper is in fact the same as the one
> used here.
> 
> Maybe more tests should be done to ensure the change is solid, I hope to
> seek some suggestions from everyone who has any ideas, or this is enough
> then it's good.
> 
> Best regards,
> I Hsin Cheng
> ---
>  kernel/time/clocksource.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
> index bb48498ebb5a..12ff0c048570 100644
> --- a/kernel/time/clocksource.c
> +++ b/kernel/time/clocksource.c
> @@ -323,9 +323,7 @@ static void clocksource_verify_choose_cpus(void)
>  		return;
>  
>  	/* Make sure to select at least one CPU other than the current CPU. */
> -	cpu = cpumask_first(cpu_online_mask);
> -	if (cpu == smp_processor_id())
> -		cpu = cpumask_next(cpu, cpu_online_mask);
> +	cpu = cpumask_first_but(cpu_online_mask, smp_processor_id());
>  	if (WARN_ON_ONCE(cpu >= nr_cpu_ids))
>  		return;
>  	cpumask_set_cpu(cpu, &cpus_chosen);
> -- 
> 2.43.0