From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 AFA3E2F362F for ; Thu, 21 Aug 2025 20:07:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755806855; cv=none; b=qP/BQYTGFoGKrxz+U8LuWBxlV/4bxhWlVPSsLnKx4IXE8/gGmmX082tYMyhF4WYf4oD6FnxCs42wopR0xsgIacGGnkNZsQ13vd8wHCX0GNocKRp2TaYZBRXji+pnCenL8CTJiWvtfhwLRCbRXAM3JEXc3AnvUx32ZD4VSOsvT04= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755806855; c=relaxed/simple; bh=ncGz2ZUizfxPtBenqYCMYHXawyPm3K75je3+1YWzFIk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:content-type; b=VJ1pqrK0mPc4qDSaiET78XGU+WWGFDWbYTMgKx/3THH/INOKYcVVS9qCxPC1kW6yrA63sG94TsmXjHVUFhQLP3VgsZhsJ261hVaeowMumLZiHM9YFW/N6z5O3hXnYV98kljDZZBmOqlg+lCpeBPZwHTTM0D6H0eXDOtGdF1j+M0= 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=VeBAVrOi; arc=none smtp.client-ip=170.10.133.124 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="VeBAVrOi" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1755806852; 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=G9hzYOZv6YXUN4v1wicJ53nqMhopJDezqYU76J2buLg=; b=VeBAVrOi7cMxlUiYW8SoxD87n24+6Clf5QZOY6oNbvz5GGSHa760IINbspI1FcV1fURR7i czuib7xp5VRPjCHNu99CNa+7BE7k0bIrp8DQFg+ZK3yzEmqpYeAyb50LYqYdLvI3UI+6tY ZKn6jENeKkH1OWciklnx/zcrOJqBfcU= 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-410-NffbDbvVP_SlYcwGaYaX5w-1; Thu, 21 Aug 2025 16:07:31 -0400 X-MC-Unique: NffbDbvVP_SlYcwGaYaX5w-1 X-Mimecast-MFC-AGG-ID: NffbDbvVP_SlYcwGaYaX5w_1755806850 Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-45a1b0b6466so9581975e9.2 for ; Thu, 21 Aug 2025 13:07:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1755806850; x=1756411650; 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=G9hzYOZv6YXUN4v1wicJ53nqMhopJDezqYU76J2buLg=; b=SUvMJUAkulGpAHU5mUShQ3jiFii5haua5bvXJqztVrnQMXcqVopyz8JBdQQTJr/3q/ LKroEvWTDjUDJrfaZNtF75kKEDj+oNDNWKbVFq55pqeozlQeol2toduteKk/3Xhzl66b EIjWI1NgACNVmSu1EWjx56vfnXktsfkdGhJizk1isW4+pL6ymDMhok/RL2PJTDpOZyv2 oRsZDUMll1pMS4hNdrL2NoDc9VMjmCUdLfDsq07M6rOVte+uen3uPVU45cWx50jL43Wt RpHZZp0LIUue2NPB0V68hiEZV32HpxwM963205xAT4e0x9s3TMlJrC6lQO8rK/7k1GPc l2OQ== X-Forwarded-Encrypted: i=1; AJvYcCWyi3uIXbAZGDAN5H5IhwZjFRUgveR0UB/ewXhYqcD4QyX1gWjAWDTyyeTVtIytZXtyICgQmZDqeLsrx6y2BA==@lists.linux.dev X-Gm-Message-State: AOJu0YyFDPSWMDfrZyOX4D396tWauOw7nevm2C+mNswM73IC8Wpo+k4Q ehmhjFfWUYxjEe9QYRbg2IPgMfars6sYhDVqSrir17SsrLugVd1VPvoE6NzVHIeixHj9OhysYsx UF/8JX51guOkRNpZ5qHsQkVNy1q1InOuV/RuYUPdrVI6sroE2fO4s3RnY1gbR8tD/sMgL X-Gm-Gg: ASbGncuEZH3pWM9PMgBmsuqbpZ3aD1BwxeEcLjssaPcvEpxEWqWtJNeqZ/7kCZLg2mz efkq+xIixfJj0tGIsmdEuskHoaOE+qVyuSTXN4nbFl6X6uejvzdJp1br+mTPKi182qaPHNOc+y1 URYwinAQbPRT20T8JB9IDJbQ7/OP++s42PkB/HHo3kzJUPJARVWr756OFo5tNXFK4/qnUXnltt6 P3P/jOnh7HQ6lIth0hW4pr2GDwuMlPmzPooiIcvsVuqgGTcHDo329N8G/q3ITtjrtFX0Rv76Qv2 3Q6fAAklmLfH3kEszqhJm+ux4WqAqHNLS8wwpUpxXg7nNx81uAa9KJqwhUWH+i5d+YvmlDP084g ClMHNJ5oBh4rCkVrMwi6XHg== X-Received: by 2002:a05:600c:1548:b0:459:dfde:3329 with SMTP id 5b1f17b1804b1-45b517ddbe2mr2956245e9.31.1755806850073; Thu, 21 Aug 2025 13:07:30 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHPNoTdvVqQJqQwQf/z0aFpcDb/7HunF1Y6KwbAqmFFF4D3cnAaKEmAnoGbjwE6N5eIepmoyw== X-Received: by 2002:a05:600c:1548:b0:459:dfde:3329 with SMTP id 5b1f17b1804b1-45b517ddbe2mr2955545e9.31.1755806849496; Thu, 21 Aug 2025 13:07:29 -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-3c3a8980ed5sm7242256f8f.16.2025.08.21.13.07.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 Aug 2025 13:07:29 -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 08/35] mm/hugetlb: check for unreasonable folio sizes when registering hstate Date: Thu, 21 Aug 2025 22:06:34 +0200 Message-ID: <20250821200701.1329277-9-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: RyXzIxo4EMbu8UUYJtMdnt2_CcAHC1XQbk1852_8dmk_1755806850 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Let's check that no hstate that corresponds to an unreasonable folio size is registered by an architecture. If we were to succeed registering, we could later try allocating an unsupported gigantic folio size. Further, let's add a BUILD_BUG_ON() for checking that HUGETLB_PAGE_ORDER is sane at build time. As HUGETLB_PAGE_ORDER is dynamic on powerpc, we have to use a BUILD_BUG_ON_INVALID() to make it compile. No existing kernel configuration should be able to trigger this check: either SPARSEMEM without SPARSEMEM_VMEMMAP cannot be configured or gigantic folios will not exceed a memory section (the case on sparse). Signed-off-by: David Hildenbrand --- mm/hugetlb.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 514fab5a20ef8..d12a9d5146af4 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4657,6 +4657,7 @@ static int __init hugetlb_init(void) BUILD_BUG_ON(sizeof_field(struct page, private) * BITS_PER_BYTE < __NR_HPAGEFLAGS); + BUILD_BUG_ON_INVALID(HUGETLB_PAGE_ORDER > MAX_FOLIO_ORDER); if (!hugepages_supported()) { if (hugetlb_max_hstate || default_hstate_max_huge_pages) @@ -4740,6 +4741,7 @@ void __init hugetlb_add_hstate(unsigned int order) } BUG_ON(hugetlb_max_hstate >= HUGE_MAX_HSTATE); BUG_ON(order < order_base_2(__NR_USED_SUBPAGE)); + WARN_ON(order > MAX_FOLIO_ORDER); h = &hstates[hugetlb_max_hstate++]; __mutex_init(&h->resize_lock, "resize mutex", &h->resize_key); h->order = order; -- 2.50.1