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Date:   Thu, 11 Aug 2022 22:28:27 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Ingo Molnar <mingo@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        stable@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Peter Xu <peterx@redhat.com>, Hugh Dickins <hughd@google.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        John Hubbard <jhubbard@nvidia.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Mel Gorman <mgorman@suse.de>
Subject: Re: [PATCH] sched/all: Change BUG_ON() instances to WARN_ON()
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On Thu, Aug 11, 2022 at 01:43:09PM -0700, Linus Torvalds wrote:
> May I suggest going one step further, and making these WARN_ON_ONCE() instead.
> 
> >From personal experience, once some scheduler bug (or task struct
> corruption) happens, ti often *keeps* happening, and the logs just
> fill up with more and more data, to the point where you lose sight of
> the original report (and the machine can even get unusable just from
> the logging).

I've been thinking about magically turning all the WARN_ON_ONCE() into
(effectively) WARN_ON_RATELIMIT().  I had some patches in that direction
a while ago but never got round to tidying them up for submission.