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Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1q1IwC-009kVr-LA; Tue, 23 May 2023 03:43:52 +0000 Date: Tue, 23 May 2023 04:43:52 +0100 From: Matthew Wilcox To: David Rientjes Cc: David Hildenbrand , Andrew Morton , Michal Hocko , Alex Shi , Johannes Weiner , Alexander Duyck , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Linus Torvalds Subject: Re: [patch] mm, debug: allow suppressing panic on CONFIG_DEBUG_VM checks Message-ID: References: <53dd9df8-e88f-f466-89f9-3fa141a10267@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <53dd9df8-e88f-f466-89f9-3fa141a10267@google.com> X-Rspamd-Queue-Id: C10BCA0007 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: rbheni7jnsfeqns96qzqn4bd5oae3iwc X-HE-Tag: 1684813441-699333 X-HE-Meta: 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 GZzb76Ta WHaEubu6kOqKREtUwrboyVXW4+zlold8pfN/6jk+EofEBdlgBX8x7eed0toZsCUo2B5519k69Rn0X4fashcCLNuYp3XlBeea2YIdaRAACLyYwClf7ij9Cpx8dIDGlrGRQYXx0eqTGdXWLLuhRGUM26GSKRCukM2YGJuHDAXxApGIoCWmB2GPYcgAdJg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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.