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Donenfeld" , linux-kernel@vger.kernel.org, patches@lists.linux.dev, tglx@linutronix.de, linux-crypto@vger.kernel.org, linux-api@vger.kernel.org, x86@kernel.org, Greg Kroah-Hartman , Adhemerval Zanella Netto , Carlos O'Donell , Florian Weimer , Arnd Bergmann , Jann Horn , Christian Brauner , David Hildenbrand , linux-mm@kvack.org References: <20240707002658.1917440-1-Jason@zx2c4.com> <20240707002658.1917440-2-Jason@zx2c4.com> <1583c837-a4d5-4a8a-9c1d-2c64548cd199@redhat.com> <6705c6c8-8b6a-4d03-ae0f-aa83442ec0ab@redhat.com> <7439da2e-4a60-4643-9804-17e99ce6e312@redhat.com> 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: <7439da2e-4a60-4643-9804-17e99ce6e312@redhat.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-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 2D692A001F X-Stat-Signature: rhtjknn1unu3gusqmd9d6riswrqdzko6 X-HE-Tag: 1720427000-908098 X-HE-Meta: U2FsdGVkX1+AoDZRYzvpRrj3fxw/OEPgqWpmo9qfDD4/78axenJnL0v5RamOI4SyKKf07iMdGCBrVAXxIarxA60i1cm+mfFW4bJqLwDcDW/hDjYFyA9zUuC7NGulIgDaz4XHYXBqvYJj3nv05b/E8HMroxQbwPme7ICIFm+hr4yETVWmEq7UH3VpgjJtUvYYl3ds5QzyyLaiG+VORjxNzdYfStDQ0SiqybVUiEtTEduvx/r88ReeJtJhWtsLGGTfS4mECIgEpqO5g1uL/R95J3AnpfY3n09SZRpQcVXb/6A8hQBXbG5quqm2sDHsI9d6KnCASmCpZianK4xiioRY1+UhsivU5xvo12xgzVlgQgXhgEVadDes3Y9P9PxRWo6fTEY674VbNYFME0oyWeEH3dqhDAKWvI41NOmBht+/xXnXQSVKWEeBahBTAyvcfpFI9NonJWX4Tcj9t1gEYT/qgiBxLpowtyQEZOoy1+L8EAquAwzHb0Y14iSSWjF5QiZ2LanIM701WQbj1a2aQgsuEMpQf3EaCNCtUQ1Ws7tYpXB/UQat0IEGYcpKpcmIu/2DL5Oc+/jb/rpsmsax7l9H1TEGe7NaCgrXnFMTtdF2/35t74BYB1MA98pG8N1XPZ/OTbc5caVHUIQ794TCxHVP24rZq3eS/5Kh4llMUy0/9wyBm2ZTngwffkHj+1St90RG0+RH3+ZOAXpR0iPy0TbMD31BR08dbpQVkoJSVU09azaD2TzscIqgJXxcMO1mBQNVRTP2plyYfdjjI1Aid0i0Pex37i9C7iahT/JSukBj3oAjPjLtbrmvgSSOpABupaqKsxL8M4Nz9L5G6Hm/A3FV5QAGZySVRwuLdGquLpmgqs4RBCWxn3Xm6f40GBIumbq+NLlMsKgjL/6jJ2so+RayhDqUY7lVMTajikzPm9fbFszQ7yTARRW+ecBQHioMeqOzEZQ4aSrF+yM0yDIIu4f 0Sm5SniV 1PbsjHbDpXOd43QE5R5WI03HXjz1AF+WBSGlmF4yrHOzBqVEC3NECkbCKoQ4ckcvTQ5LKSat9JFC4bKB2GDTUV92X0z50ekWbT5kasoSp/zfwkt4ZV5JAi6ZybpyyUTOxNNROzqk0+pgBQgTmG1ch/NKLVkqeGoROFn/aYsUqRFccr51E8tJeNcB7wjuMXNZL3MYhKkPf+thRKVnwi6Ybx65PPOu+qAMh7A4ZUcj6pcBsOfkMtiRXeSPP/FtUu2iV0NRNONv0+JzLHmJLOJeZ0q/iZwT1TWrZm2GvilqlSVyhdLsFjzCftxE0+PhBCcs9wZOCOPwINEcA+pmcVg0Jy1GscohRfPo1NecwRbr3vraxlhGWwiCUJ7ZiSIDrYlX19lVwQWRq2AFcM6ueiHuBhaN4fPRM91nPAaKS0weFtuyODNHhJv+GNRocvA== 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: > As a side note, I'll raise that I am not a particular fan of the > "droppable" terminology, at least with the "read 0s" approach. > > From a user perspective, the memory might suddenly lose its state and > read as 0s just like volatile memory when it loses power. "dropping > pages" sounds more like an implementation detail. Just to raise why I consider "dropping" an implementation detail: in combination with a previous idea I had of exposing "nonvolatile" memory to VMs, the following might be interesting: A hypervisor could expose special "nonvolatile memory" as separate guest physical memory region to a VM. We could use that special memory to back these MAP_XXX regions in our guest, in addition to trying to make use of them in the guest kernel, for example for something similar to cleancache. Long story short: it's the hypervisor that could be effectively dropping/zeroing out that memory, not the guest VM. "NONVOLATILE" might be clearer than "DROPPABLE". But again, naming is hard ... :) -- Cheers, David / dhildenb