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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 14131CA0FE7 for ; Thu, 21 Aug 2025 20:07:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B376E8E002D; Thu, 21 Aug 2025 16:07:33 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A43E68E0027; Thu, 21 Aug 2025 16:07:33 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 932FB8E002D; Thu, 21 Aug 2025 16:07:33 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 812C38E0027 for ; Thu, 21 Aug 2025 16:07:33 -0400 (EDT) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 4EEF11A056F for ; Thu, 21 Aug 2025 20:07:33 +0000 (UTC) X-FDA: 83801849586.22.62AA901 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf13.hostedemail.com (Postfix) with ESMTP id 169BF20017 for ; Thu, 21 Aug 2025 20:07:30 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=YjT7EvFr; spf=pass (imf13.hostedemail.com: domain of dhildenb@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=dhildenb@redhat.com; dmarc=pass (policy=quarantine) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1755806851; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=A9Znt0atqEjtEUkbTSfKRsvBJ9rEcbnqI7Kn1XkJSrA=; b=HSgkTjphJkO/q0FaABDip63WY+8Mkk0aWa2VN54iIgtbbuovUlJgu29VZ3Plj3SLXvr4jv ZRBIeYCQAW0W9/3uQzrOxzqqsPOqNNNpc6hWPtSfHOsw3rGWOW0mdAQlE9H3Ms8fNIl2DG pMX1zQo3+ak8IAHtAIJNPTRLCHsHxsU= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=YjT7EvFr; spf=pass (imf13.hostedemail.com: domain of dhildenb@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=dhildenb@redhat.com; dmarc=pass (policy=quarantine) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1755806851; a=rsa-sha256; cv=none; b=frh+dtc78j1ce/Do4sYnmian4fqPcQbFDgtVNhYTtfzmABYsIl7lv83G04AhSEQ3FJnQHi tgNTlOJWyWenURUzK9zfGlZ8pQN4bNennNqDo1jL4eTEqVOPZz/duIOsmRQl8qwT5oEmRX OWpe6+8waLshGkQNd8Rn79u3jHQaz+I= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755806850; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=A9Znt0atqEjtEUkbTSfKRsvBJ9rEcbnqI7Kn1XkJSrA=; b=YjT7EvFrJT5scdeM5Zhxs1Qk/Cqch+J+8hIxWxlHb7nVNU02myxpnBeJveCAmU84L9yDad vtsRlwxqXN6zx8RcnWcVFKhynJbqTs2VIm3xSpDL2hddvTFVyKK/czblWXG8Igw2XVihhk Fb0YTZpxr5lzYg/3oduk7oOlhbYva1I= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-178--DRbtMESO7K_uNbQHXZLHQ-1; Thu, 21 Aug 2025 16:07:28 -0400 X-MC-Unique: -DRbtMESO7K_uNbQHXZLHQ-1 X-Mimecast-MFC-AGG-ID: -DRbtMESO7K_uNbQHXZLHQ_1755806847 Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-45b4d6f3ab0so8376805e9.0 for ; Thu, 21 Aug 2025 13:07:28 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755806847; x=1756411647; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=A9Znt0atqEjtEUkbTSfKRsvBJ9rEcbnqI7Kn1XkJSrA=; b=aD+LtW/Ftn0HRFntj5J0mMUY4V9YwMF4xk3tmVtUhFH7x7WVNXCFhFlFT3HvfCUBSz RoZV0sJn/hoAbareWC5kuayHigA6QoaXekOHfB0HC11+6MMhiOSr9RtSIy//XebmAhrT gstyr/3M7YQKu+3ebmGdEQBxnCyK2+CukZw9SIny9VusvKXN0SFy+UGG/F1AbVB3W9wU rhMm94oRma+iAmRGsUqE7ziJMHqOozslnOsRkEHY5Qkkb4BA1AGZBVI2q8+Fv5Jp7+Xr 3IEnkw240E6jclS9qTrfIb3f+sokzzEYRJeJX0j5LzrNjr1OcVBz7eSJZjq9HKrJKmWY n16A== X-Forwarded-Encrypted: i=1; AJvYcCV3ua4tJGwPR6HSSY/JTo356ZgX/Wr17CE+CUFHu0ovqDxXpOZKhDQOxKc5w9tf+CbdQmwCUdq0UA==@kvack.org X-Gm-Message-State: AOJu0YwocVZ8naT+o9JZoC0QfbTlEcOXpx4DHJYAU4iEnUk42igNLDBg o5QXPUnTtDun56X1rDQbTK6cH6HZ535ZuWRArG7mSZQZ4q1h8Xkv0drjyQ8OY+sw44JFh+xjpUx XY3mOWRVGzNccBM1MDW8uyLmDCaxd85l29fG8QOeH02mWzYrNOkr0 X-Gm-Gg: ASbGncubw2lSRESUxU+kWsDx6cwijc0YIgSRuDCZAb92ekrko+Jqtlrlfefz1w4sU0+ sPAduQFcWiYszGZ1j0oKkk91WskCWrk8bttxw97Wgzv8h+NHgC/NMx3s7cJq1ZPy2PYj0W16Y/7 Ihk58fF+bqEXqKQ65niPViQEgssnYcQX3eFzM3ULTxgyiEEJM65pE6QtZpfYPB+ch+AqckT0o73 6g9vuqb/c0rprymkh2MzpOyHYkeKBhnaPBN/X5ZIz8W0USVQ8BGSFcOBPF3IHkcHZWuBXhwEHOc R6LwCmAIAgNlXXl1dD72qxEGA2ftipvXNxuBJEFH3xJ71ldwzrBC44pTOdtoABD9qv36mHxhGMa 2A/F7Ge475iJhuA1Cmz0OCQ== X-Received: by 2002:a05:600c:3552:b0:459:dde3:1a33 with SMTP id 5b1f17b1804b1-45b517d26d4mr2922305e9.26.1755806847228; Thu, 21 Aug 2025 13:07:27 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGUeapMM5JkcwJNJXC+LM6ICHu4lGUEF2ir46AAuHXhYXAFzTcPIdec/q/lplZD/isU7mGEgg== X-Received: by 2002:a05:600c:3552:b0:459:dde3:1a33 with SMTP id 5b1f17b1804b1-45b517d26d4mr2921795e9.26.1755806846742; Thu, 21 Aug 2025 13:07:26 -0700 (PDT) Received: from localhost (p200300d82f26ba0008036ec5991806fd.dip0.t-ipconnect.de. [2003:d8:2f26:ba00:803:6ec5:9918:6fd]) by smtp.gmail.com with UTF8SMTPSA id 5b1f17b1804b1-45b50d62991sm9535385e9.0.2025.08.21.13.07.24 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 Aug 2025 13:07:26 -0700 (PDT) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: David Hildenbrand , 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: [PATCH RFC 07/35] mm/memremap: reject unreasonable folio/compound page sizes in memremap_pages() Date: Thu, 21 Aug 2025 22:06:33 +0200 Message-ID: <20250821200701.1329277-8-david@redhat.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250821200701.1329277-1-david@redhat.com> References: <20250821200701.1329277-1-david@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: fDreGTIpBPDbRd5r8bODhQ2L39yUmAIORlJBlxntnKQ_1755806847 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true X-Stat-Signature: jsefrsqfa6mddpwnak4rom5fypt6bspx X-Rspam-User: X-Rspamd-Queue-Id: 169BF20017 X-Rspamd-Server: rspam01 X-HE-Tag: 1755806850-403515 X-HE-Meta: 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 +un/cRMv 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 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: List-Subscribe: List-Unsubscribe: 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 --- mm/memremap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/memremap.c b/mm/memremap.c index b0ce0d8254bd8..a2d4bb88f64b6 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -275,6 +275,9 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) if (WARN_ONCE(!nr_range, "nr_range must be specified\n")) return ERR_PTR(-EINVAL); + if (WARN_ONCE(pgmap->vmemmap_shift > MAX_FOLIO_ORDER, + "requested folio size unsupported\n")) + return ERR_PTR(-EINVAL); switch (pgmap->type) { case MEMORY_DEVICE_PRIVATE: -- 2.50.1