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 66AEDD16261 for ; Mon, 14 Oct 2024 13:29:38 +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: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=gBjYzcRVvT12PEuEEui9pwXMfmtmAfZKGIhfMKjJ2K4=; b=0WbVcn840vjrdzitaVVd6I0JtU X5jHayEZDAxskvj3caH+AhNsUxsx4T5u/EvUe6KKF7e1X/rkOVI6pQBDEeb1rB6EL29i/1ZN5F5lU 3pjjuwovXGeZEgUPhoDsH0gwWijJjSLEj3OfInzCPfM13eL6P1dOj1Z5LaNc6+I9yfNWeTr5BMCKw VVxWbCV7Gjo3SHd0aO5p9nxk/n/IrwyrX7mXScNKdh1WAWC5IHFHPcQ/3gf/MQgtzgiCM5j/W5/nN gPLJC7ci2mPlkXv2+IE665KfbMiYL85ppIdggxBpio5R/+44Je/sSSweo+YXHkqfUsjC/0ldPbuAE eL85L+/w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t0L8Z-00000005HUa-1NSU; Mon, 14 Oct 2024 13:29:27 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t0JYQ-00000004yvR-1MwQ for linux-arm-kernel@lists.infradead.org; Mon, 14 Oct 2024 11:48:03 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1728906481; 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:autocrypt:autocrypt; bh=gBjYzcRVvT12PEuEEui9pwXMfmtmAfZKGIhfMKjJ2K4=; b=Xf6VB67xpK/3LtbwZRnnD+BkOtsXk9V8i6KIGwBShYfW/fcYHtSMNsmg1t+vRqJndAR+H4 svwkQYGWm0JEPJia3ubW5LBuIf3/EX4h3fA+EVrrEuIwfllBx4TvLrgy0rQHX8v9uraNYY lOogNzkMrdW02CoJlSsVDhn33Ml7BME= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-665-nBz_m_-NNiCFgNirb0keRQ-1; Mon, 14 Oct 2024 07:46:08 -0400 X-MC-Unique: nBz_m_-NNiCFgNirb0keRQ-1 Received: by mail-wr1-f70.google.com with SMTP id ffacd0b85a97d-37d5116f0a6so1407834f8f.0 for ; Mon, 14 Oct 2024 04:46:07 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728906367; x=1729511167; h=content-transfer-encoding:in-reply-to:organization:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=gBjYzcRVvT12PEuEEui9pwXMfmtmAfZKGIhfMKjJ2K4=; b=VyqJ/IZR8Cupb29TDrqSTf/AxV8kAzZMhUEIkw+0U6jtiyum4DPzPimep352MhtgLx WQiVAW/UK6kVs4CUJk/qxEKjsrs8Gay1PBFwK+F7SZe3LdpVQWDRmQxfFZvR2gI2+ajr bxp8JLcX9K9DpGp4y1xTevADniehmu6Sbi9t59OdOx5/r/0vPcn77mBsb8jWycSW/JPq INlEign9YX1D+CvHvnNKH1vmGoUpfOMx9KtJJhhbnyeF84mkMHcflH0Vg7wB7PSFhTv6 3kgTqrmdtKMBKtLt7wHGqhk4lU5OfTyGY0mpUfyOFwmwbK6viywH4QnnnvYyNqD5J/J9 04uA== X-Forwarded-Encrypted: i=1; AJvYcCWtZDI/HjaGmbbzfpnqMLTFMDPu0fcaQZaMVLYhXbO83NV1NVoOEJDX7hi86VY7l0+WshABcX9nhIyHjmJ2xiBg@lists.infradead.org X-Gm-Message-State: AOJu0YyC8E/c8iCRnR0HbK+XsjFpCZdRO0Grs7yLv0pw9IL+N9gD5yYp StI1Movczn6wK8AEg+9wFIUi+9qj3GEtQtqXLQOLFkguvp5mEUZE32wQw3fCGBu4RsVA7ID0guf AjmvoR/pejZqO+cFQJPMLYMxV1UNTdNdIsgIifwxqIMLdOTOHBzw75FDevxOgvpqUVXOnuF9e X-Received: by 2002:a5d:4bc7:0:b0:37d:5257:41bd with SMTP id ffacd0b85a97d-37d5fe9563bmr5646872f8f.3.1728906366842; Mon, 14 Oct 2024 04:46:06 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGy4+eK7AI1hvF0chp44blw4HV74w/vDgNn4hR29csqzaMxakWWq4fE61CpHPmk22Wnjjh4wA== X-Received: by 2002:a5d:4bc7:0:b0:37d:5257:41bd with SMTP id ffacd0b85a97d-37d5fe9563bmr5646848f8f.3.1728906366399; Mon, 14 Oct 2024 04:46:06 -0700 (PDT) Received: from ?IPV6:2a09:80c0:192:0:5dac:bf3d:c41:c3e7? ([2a09:80c0:192:0:5dac:bf3d:c41:c3e7]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-37d4b79f9a9sm11208067f8f.74.2024.10.14.04.46.04 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 14 Oct 2024 04:46:05 -0700 (PDT) Message-ID: <38b5649b-0e4b-460c-8097-04c530fbfa46@redhat.com> Date: Mon, 14 Oct 2024 13:46:04 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] kaslr: rename physmem_end and PHYSMEM_END to direct_map_physmem_end To: John Hubbard , Andrew Morton Cc: Thomas Gleixner , Will Deacon , Alistair Popple , Jordan Niethe , linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-mm@kvack.org, LKML References: <20241009025024.89813-1-jhubbard@nvidia.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: <20241009025024.89813-1-jhubbard@nvidia.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241014_044802_449300_328DCB91 X-CRM114-Status: GOOD ( 15.76 ) 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 09.10.24 04:50, John Hubbard wrote: > For clarity. It's increasingly hard to reason about the code, when KASLR > is moving around the boundaries. In this case where KASLR is randomizing > the location of the kernel image within physical memory, the maximum > number of address bits for physical memory has not changed. > > What has changed is the ending address of memory that is allowed to be > directly mapped by the kernel. > > Let's name the variable, and the associated macro accordingly. > > Also, enhance the comment above the direct_map_physmem_end definition, > to further clarify how this all works. > > Cc: Thomas Gleixner > Cc: Alistair Popple > Cc: Jordan Niethe > Cc: David Hildenbrand > Signed-off-by: John Hubbard > --- > > David Hildenbrand, I recall you had an unanswered question in this > vicinity [1] when tglx's recent kaslr fix was being reviewed. Maybe this > will help with that. Yes, that makes it clearer for me, thanks Acked-by: David Hildenbrand -- Cheers, David / dhildenb