From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 268072C0273 for ; Thu, 21 Aug 2025 20:07:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755806850; cv=none; b=MgSnY2/rOLTSDDybszAoaUY7w6ICmPFK075sL+MFfpYU4M6D72reSTgNUV+2LQre6paZdGdUnIBVdpHANqutIZMMR1osEKEaej5z7W1cy0HnKzGcJcYX0lziryNYrMqu8k3oqoGy6h4U38QR/0p8s7yKT0wXJUUM9x6arrg4c7A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755806850; c=relaxed/simple; bh=hFKonsreRzgICf2+ZQw2cwOexdUd6KjiPB+Q505LSVk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:content-type; b=I8cFmDlWmyNdt1eTXht4f1pA4ImIeFhX165FmGoVepSDXzlYZxGh6XkLtVqf0SjhM1+gWP/C7YV+DoDsHCgGzWx19Ws6nxh8fbyzz9x9BSBe02lM9d3Q/ol/n7vQXoHYDrVg8xM8rsp8L45V76OdhGDp6vB8iU1+cJn2m668JHs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=dBdGbLGc; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dBdGbLGc" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755806847; 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=saIpwl0G6zoDDZA6kqzaAKGDHCkLp/ivw/dNNi90asQ=; b=dBdGbLGcVbRa9Ikps2KwOnaoL4YsVb8wdAXF6ARS144K7GPVFJrdibgBt7thHpBMe1Vgzy 68z0YKbhgXTw55s7BNSlH/0FOyk4bm7wyBFmjdho+lGObZK2cz0zVmk81MszaIIKKpdo7B Tot+dhPdVLSrkCrClPDcdtWNEXv5Qhc= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-629-p3IbYsj5NLGeDBcYSrFvrg-1; Thu, 21 Aug 2025 16:07:25 -0400 X-MC-Unique: p3IbYsj5NLGeDBcYSrFvrg-1 X-Mimecast-MFC-AGG-ID: p3IbYsj5NLGeDBcYSrFvrg_1755806845 Received: by mail-wm1-f70.google.com with SMTP id 5b1f17b1804b1-45a1ba17bbcso7094335e9.0 for ; Thu, 21 Aug 2025 13:07:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755806844; x=1756411644; 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=saIpwl0G6zoDDZA6kqzaAKGDHCkLp/ivw/dNNi90asQ=; b=Iql76eDocIe1jDuB9TsII3BgHoUXl6TspnFplgdLQaCmSGGg5n+ET9KvMxdwUmLP3r 3WK4/lxVyM2oUFmtoEWlSnKq0vMVeSOVoliVgA94SMepQIiadpfI5cxAk00yy2oMgsIp McelXIEihpZYv5G6x1bkmE1b5AsBCY76zorFE//C7jhVR4dkBOKE5Jpfh9OO/GJuFQON 1RHEHwTnuTxavlkr7Grh75kDcw5mm34Hwqv7LT+DT1kuN2S0lAF1ulm3SiuwceyhiVpE eOcsdKMiqYSWvoYAOEAoMAR0Xx5U8BcXpTdRnqgbRrgLQ5FPUrVm1xfJzKkNFSNowby4 1ZUA== X-Forwarded-Encrypted: i=1; AJvYcCXm3S32E0WfPoZT5oXUybgBFLm5hn03SIH/PTT03v35ECbMPthvjSwhoGI6w3Ptzil85bsX2uh+mqhVzTsyDw==@lists.linux.dev X-Gm-Message-State: AOJu0YxSS+sr38I0anYGhfV/645ZBDRJlSq7eAoYvqqW8QL5cuyd1HLo bdu+6zXCiNDTgZ9CTzcoiubii+d5U3czUoUHKX6IOlfvgNHY0wJTkSVH2+XNu090mqYGYY+csUV P6HKVyVQ9eGDrzJVALiHqxt2dB2MBPoVdLmgPu1oHZG7RhJxzKjEo3x4sP8GEr2dWU6lT X-Gm-Gg: ASbGnctr2YEmsVJiaJlGWPAPsViDiO0ngeTffCctUdDk5Dotjzk1wZlRZrheupD3zU2 Lvn5a0/SZ33zB3/3DRtBHN9unoMjQNOhCpY5Fsp83Mi0xSUx9fga2hdpKA4S4UoZE7r4zOBMsjB WY+MHewXfig6zYpOUifSE9pZBZmhm6zbDHRmcd/DbjjrY26dQWXAYvOB8wf8H9XNY6swYrSfvVr CMu/9ZgvyqdrOYPwY/ixX1BlPSUWl7Hatf8YlEf+vuU0qNuMSCI5Iu4tvmhVLA0Vj6NJgsOC9LY 68Ge9/umme9jUcWgX03Of2i+rpCDaItfOcg8H9IjQqQocLC/ouHAxEoaDbj8Wl+1O02uzkVhSOa nmIpM3pGRBLM58cCowKz/sA== X-Received: by 2002:a05:600c:35c3:b0:456:285b:db3c with SMTP id 5b1f17b1804b1-45b5178e768mr3050365e9.3.1755806844567; Thu, 21 Aug 2025 13:07:24 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFwjTyvRglWWHHllkR7aRLdEFYS2lmKXV2DYH9bn4L7+YG6UNdB0HbBuiJbZZ1vy18QyYWFNg== X-Received: by 2002:a05:600c:35c3:b0:456:285b:db3c with SMTP id 5b1f17b1804b1-45b5178e768mr3049835e9.3.1755806844048; Thu, 21 Aug 2025 13:07:24 -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 ffacd0b85a97d-3c074e38d65sm12980909f8f.27.2025.08.21.13.07.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 Aug 2025 13:07:23 -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 06/35] mm/page_alloc: reject unreasonable folio/compound page sizes in alloc_contig_range_noprof() Date: Thu, 21 Aug 2025 22:06:32 +0200 Message-ID: <20250821200701.1329277-7-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> Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: -A7e1F6IPs6JeXYEdgpL1zitkVxuQwtDiYXvtE0UV4w_1755806845 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Let's reject them early, which in turn makes folio_alloc_gigantic() reject them properly. To avoid converting from order to nr_pages, let's just add MAX_FOLIO_ORDER and calculate MAX_FOLIO_NR_PAGES based on that. Signed-off-by: David Hildenbrand --- include/linux/mm.h | 6 ++++-- mm/page_alloc.c | 5 ++++- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 00c8a54127d37..77737cbf2216a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2055,11 +2055,13 @@ static inline long folio_nr_pages(const struct folio *folio) /* Only hugetlbfs can allocate folios larger than MAX_ORDER */ #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE -#define MAX_FOLIO_NR_PAGES (1UL << PUD_ORDER) +#define MAX_FOLIO_ORDER PUD_ORDER #else -#define MAX_FOLIO_NR_PAGES MAX_ORDER_NR_PAGES +#define MAX_FOLIO_ORDER MAX_PAGE_ORDER #endif +#define MAX_FOLIO_NR_PAGES (1UL << MAX_FOLIO_ORDER) + /* * compound_nr() returns the number of pages in this potentially compound * page. compound_nr() can be called on a tail page, and is defined to diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ca9e6b9633f79..1e6ae4c395b30 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6833,6 +6833,7 @@ static int __alloc_contig_verify_gfp_mask(gfp_t gfp_mask, gfp_t *gfp_cc_mask) int alloc_contig_range_noprof(unsigned long start, unsigned long end, acr_flags_t alloc_flags, gfp_t gfp_mask) { + const unsigned int order = ilog2(end - start); unsigned long outer_start, outer_end; int ret = 0; @@ -6850,6 +6851,9 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end, PB_ISOLATE_MODE_CMA_ALLOC : PB_ISOLATE_MODE_OTHER; + if (WARN_ON_ONCE((gfp_mask & __GFP_COMP) && order > MAX_FOLIO_ORDER)) + return -EINVAL; + gfp_mask = current_gfp_context(gfp_mask); if (__alloc_contig_verify_gfp_mask(gfp_mask, (gfp_t *)&cc.gfp_mask)) return -EINVAL; @@ -6947,7 +6951,6 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end, free_contig_range(end, outer_end - end); } else if (start == outer_start && end == outer_end && is_power_of_2(end - start)) { struct page *head = pfn_to_page(start); - int order = ilog2(end - start); check_new_pages(head, order); prep_new_page(head, order, gfp_mask, 0); -- 2.50.1