Re: [PATCH v6] hung_task: Deduplicate identical hang reports using explicit blocker tracking

[Aaron Tomlin]

On Wed, Jul 22, 2026 at 10:10:18AM +0800, Lance Yang wrote:
> 
> On Tue, Jul 21, 2026 at 01:30:34PM -0400, Aaron Tomlin wrote:
> >On Tue, Jul 21, 2026 at 03:28:48PM +0200, Petr Mladek wrote:
> [...]
> >
> >> 3. We could prevent printing the same process again and again
> >>    by adding "hung_task_reported" into struct task_struct.
> >> 
> >>    But then we should print some summary about how many hung tasks
> >>    were found in the last round at least. So that we know that
> >>    the problem persists.
> >> 
> >>    This should still be rather easy. But I am not sure if it is
> >>    worth it.
> >> 
> >> 4. We could add the filtering of the duplicated backtraces. But
> >>    it has to be handled by some helper function.
> >> 
> >>    It looks like to most complicated part. I would personally skip
> >>    it for now. We could always add it later when the above proposed
> >>    changes are not enough to tune the kernel.hung_task_warnings
> >>    value in the real life.
> >
> >I do think this is worth doing to prevent the single-line spam if a task
> >remains hung for hours, no?
> 
> Nope.
> 
> TBH, if a task is still stuck hours later, something is already gone
> sideways. Seen that play out plenty of times: hung task, soft/hard lockup,
> panic, reboot. Hard to call that one-liner spam :)
> 
> So yeah, I still think v7 should just go with Petr's two patches. That
> should take care of the problems we're trying to solve ;)
> 
> @Aaron mind taking those, testing them out, and spinning a v7?
> 

Hi Lance,

No problem—I'll take care of it.

Kind regards,
-- 
Aaron Tomlin