From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D6399CA0EFA for ; Sat, 23 Aug 2025 06:41:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=NJaCLxCq3XCnWLFFwVYzAYFNIZQDOhDO2V5KPJHlnOY=; b=Mq4ZqhU7kgBOa4ZNc4GWjvFqFK lauucTVBpqlO3OrhALDfO8SeqzH7OWQze0sk2xuXC2ys9P/URT2aDJeNf0CUvxBFHbmoLrn+oJsEQ hkvLQSz8IuU0JFZ6+10b8ohJpItauQ4XToBXKFW/i0DTEaGnOu93qJu0EgAaIXDbJpx9aBbJq253B 88pThlxorF9pBp/dxPTFrdxvkuKfI8dMBuoi1oOR2rJ4M+N6XoeTq8r6JaAZ9Cai765NZq9DiX1+B stlVkIV8B3E8oOkvKWZPdwaQ3Dtc7nC6t9V7m3uC3DptoABPK0ZddyTtons8RKPw1RufZzXRXn16E CMetvu6Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uphvx-00000004CbE-2SPM; Sat, 23 Aug 2025 06:41:01 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1upVH0-00000003Don-1N2q; Fri, 22 Aug 2025 17:09:54 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id BE2F160203; Fri, 22 Aug 2025 17:09:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 506C3C4CEED; Fri, 22 Aug 2025 17:09:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755882593; bh=NEyazjWgDDK3Y8sTMLiPKtOTS94IEzEQJlr1MXdW648=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DmWBU4VzSCcAnl6Zdrhjx6ksjldQdRyRt8SGGJHoy1Xwe7M0wFFiAnOgc7AY/DT0q lyqL/1TbY9lw6Mk6ofMnsxQa0R5tG+ekC6WUSLcyfnxUCURU/dBA0VxXY7c6IJ9LBi dspILvQPKUlPvqhEvwNtu+fRhuKR7/IUmABwpf10OfXceruEb+htOjuVlClrNaqJfU QZNtMHJYtlsQdWeTBL2WlQglN7zceCD+RoTlZDKPvwA5Fz0NZs4QmCTFXTFDq7ZuUg eXWdY/p99/aQ44iT5rRcus/JttgHgvk0uE55mO5Gfzz0M9Zot8coHQnhPz2Tn/edlI y9z5UNwm6HZrw== From: SeongJae Park To: David Hildenbrand Cc: SeongJae Park , linux-kernel@vger.kernel.org, Alexander Potapenko , Andrew Morton , Brendan Jackman , Christoph Lameter , Dennis Zhou , Dmitry Vyukov , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, iommu@lists.linux.dev, io-uring@vger.kernel.org, Jason Gunthorpe , Jens Axboe , Johannes Weiner , John Hubbard , kasan-dev@googlegroups.com, kvm@vger.kernel.org, "Liam R. Howlett" , Linus Torvalds , linux-arm-kernel@axis.com, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-ide@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mips@vger.kernel.org, linux-mmc@vger.kernel.org, linux-mm@kvack.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, Lorenzo Stoakes , Marco Elver , Marek Szyprowski , Michal Hocko , Mike Rapoport , Muchun Song , netdev@vger.kernel.org, Oscar Salvador , Peter Xu , Robin Murphy , Suren Baghdasaryan , Tejun Heo , virtualization@lists.linux.dev, Vlastimil Babka , wireguard@lists.zx2c4.com, x86@kernel.org, Zi Yan Subject: Re: [PATCH RFC 07/35] mm/memremap: reject unreasonable folio/compound page sizes in memremap_pages() Date: Fri, 22 Aug 2025 10:09:51 -0700 Message-Id: <20250822170951.53418-1-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250821200701.1329277-8-david@redhat.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, 21 Aug 2025 22:06:33 +0200 David Hildenbrand wrote: > Let's reject unreasonable folio sizes early, where we can still fail. > We'll add sanity checks to prepare_compound_head/prepare_compound_page > next. > > Is there a way to configure a system such that unreasonable folio sizes > would be possible? It would already be rather questionable. > > If so, we'd probably want to bail out earlier, where we can avoid a > WARN and just report a proper error message that indicates where > something went wrong such that we messed up. > > Signed-off-by: David Hildenbrand Acked-by: SeongJae Park Thanks, SJ [...]