Re: [PATCH linux-next] mark access to tick_do_timer_cpu with READ_ONCE/WRITE_ONCE

[Thomas Gleixner]

On Mon, Jan 09 2023 at 13:51, Frederic Weisbecker wrote:
> On Mon, Dec 19, 2022 at 01:21:28PM +0800, Zhouyi Zhou wrote:
>> fix above bug by marking access to tick_do_timer_cpu with READ_ONCE/WRITE_ONCE
>
> This has been discussed before with passion:
>
> http://archive.lwn.net:8080/linux-kernel/1C65422C-FFA4-4651-893B-300FAF9C49DE@xxxxxx/T/
>
> To me data_race() would be more appropriate but that would need a changelog with
> proper analysis of the tick_do_timer_cpu state machine.

Proper analysis and comments in the code are required independent of
READ/WRITE_ONCE() or data_race().

Thanks,

        tglx