Re: [PATCH v2] ring-buffer: Skip time delta validation for the counter clock

[Steven Rostedt]

On Wed, 4 Nov 2026 14:42:00 -0800
Kirtikumar Anandrao Ramchandani <kirtiar15502@xxxxxxxxx> wrote:

> The counter trace clock increments on every read. Time delta validation
> assumes that the clock values read while reserving and checking an event
> can be reconciled with the deltas stored in the page. With the counter
> clock, this assumption can fail for an intact ring buffer and report a
> spurious TIME DOES NOT MATCH warning.
> 
> Skip time delta validation while the buffer uses trace_clock_counter().
> Clock selection already resets the buffer, so events recorded under a
> previous clock are not retained for this check. Recording and reading
> counter-clock events are unchanged.
> 
> Link: https://lists.openwall.net/linux-kernel/2026/09/20/1283

Nit, the above should be a lore link, but thanks for doing my todo ;-)

-- Steve

> Reported-by: syzbot+eb74dca0d1eb3ec227a7@xxxxxxxxxxxxxxxxxxxxxxxxx
> Closes: https://syzkaller.appspot.com/bug?extid=eb74dca0d1eb3ec227a7
> Signed-off-by: Kirtikumar Anandrao Ramchandani <kirtiar15502@xxxxxxxxx>
> ---