Re: [PATCH v4 06/18] tracing/remotes: Add dmesg tracefs file
From: Vincent Donnefort
Date: Tue Aug 11 2026 - 10:20:26 EST
On Tue, Aug 11, 2026 at 09:48:57AM -0400, Steven Rostedt wrote:
> On Tue, 11 Aug 2026 10:09:27 +0100
> Vincent Donnefort <vdonnefort@xxxxxxxxxx> wrote:
>
> > > > This is a pre-existing issue, but if an oversized event causes
> > > > trace_remote_iter_print_event() to return -EOVERFLOW, will this break
> > > > the loop without calling trace_remote_iter_move()?
> > > >
> > > > Since the event is left unconsumed in the buffer, could this lead to an
> > > > uninterruptible infinite loop (hard lockup) when reading the trace pipe?
> > >
> > > I'll let you answer the above.
> > >
> > > -- Steve
> >
> > I don't believe this can realistically happen, trace_seq buffer is 8K and remote
> > events are really small.
>
> They are small until they are not ;-)
>
> Is there anything that forces their size to be small?
>
> -- Steve
I don't see anything preventing the declaration of a massive print function at
the moment...
... and neither the registration of an event with a size bigger than a page.
Is it something we should consider? I have ignored it (in both trace_remote and
simple_ring_buffer) as it seems very much unlikely anyone would do that.
--
Vincent