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Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Sun, 21 Aug 2022 13:28:58 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Mel Gorman <mgorman@suse.de>
Cc:     Linus Torvalds <torvalds@linux-foundation.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>,
        Matthew Wilcox <willy@infradead.org>,
        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>
Subject: Re: [PATCH v2] sched/all: Change all BUG_ON() instances in the
 scheduler to WARN_ON_ONCE()
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* Mel Gorman <mgorman@suse.de> wrote:

> For the rest, I didn't see obvious recovery paths that would allow the 
> system to run predictably. Any of them firing will have unpredictable 
> consequences (e.g. move_queued_task firing would be fun if it was a 
> per-cpu kthread). Depending on which warning triggers, the remaining life 
> of the system may be very short but maybe long enough to be logged even 
> if system locks up shortly afterwards.

Correct. I'd prefer to keep all these warnings 'simple' - i.e. no attempted 
recovery & control flow, unless we ever expect these to trigger.

I.e. instead of adding a 'goto' I'd prefer if we removed most of the ones 
you highlighted. But wanted to keep this first patch simple.

Thanks,

	Ingo