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Date:   Tue, 23 May 2023 04:43:52 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     David Rientjes <rientjes@google.com>
Cc:     David Hildenbrand <david@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Michal Hocko <mhocko@kernel.org>, Alex Shi <alexs@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Alexander Duyck <alexanderduyck@fb.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [patch] mm, debug: allow suppressing panic on CONFIG_DEBUG_VM
 checks
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On Mon, May 22, 2023 at 11:39:27AM -0700, David Rientjes wrote:
> I think VM_BUG_ON*() and friends are used to crash the kernel for 
> debugging so that we get a crash dump and because some variants don't 
> exist for VM_WARN_ON().  There's no VM_WARN_ON_PAGE(), for example, unless 
> implicitly converted with this patch.

It could be added, but there's already a VM_WARN_ON_FOLIO() and
VM_WARN_ON_ONCE_PAGE(), so hopefully we just keep converting code
to folios until nobody notices that we might need such a thing.