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Date: Tue, 17 Dec 2024 14:07:50 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami
 Hiramatsu <mhiramat@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, Andrew Morton
 <akpm@linux-foundation.org>, stable@vger.kernel.org
Subject: Re: [PATCH 1/3] ring-buffer: Add uname to match criteria for
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On Tue, 17 Dec 2024 11:03:28 -0800
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Tue, 17 Dec 2024 at 10:42, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > My initial suggestion was to just fix up the boot time array.
> >
> > I think that's actually wrong. Just print the raw data and analyze it
> > in user space.  
> 
> .. I still think it's not the optimal solution, but fixing up the
> event data from the previous boot (*before* printing it, and entirely
> independently of vsnprintf()) would at least avoid the whole "mess
> with vsnprintf and switch the format string around as you are trying
> to walk the va_list in sync".
> 
> Because that was really a non-starter. Both the format string hackery
> and the va_list hackery was just fundamentally bogus.
> 
> If you massage the data before printing - and independently of it -
> those two issues should at least go away.

But I can't massage the data without the deltas. That takes us back to
having to have the same kernel and only processing kernel core data and
ignoring modules.

-- Steve