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Howlett" , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jason Gunthorpe , Peter Xu References: <20250604140544.688711-1-david@redhat.com> <8e85a701-7791-46d9-9443-266c6049c01f@suse.cz> 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: <8e85a701-7791-46d9-9443-266c6049c01f@suse.cz> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: Tb0ZlS08RtJkOfAQpq8oJl5Ne-0WaWsBUcVse_nvvBg_1749126544 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 7790640004 X-Stat-Signature: r7wdtqd6d17ziyy1nbxr7o6mua9dpcr8 X-Rspam-User: X-HE-Tag: 1749126546-396645 X-HE-Meta: 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 5yVX04Yr mKwjsbvJhjDTvRRrjVs8VH5CUgL7c2O2MsnP4x0DIxSunTQ5kUAa41lwiLGFx7QxDfb5SBi25GW8DKREB3nTJluIVnnXNGDg6A0XAGcajLZffdD34bBFTGu4FW9QcPREQf8ky 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: On 05.06.25 10:48, Vlastimil Babka wrote: > On 6/5/25 08:08, David Hildenbrand wrote: >> On 05.06.25 07:37, Vlastimil Babka wrote: >>> On 6/5/25 03:07, John Hubbard wrote: >>>> On 6/4/25 7:05 AM, David Hildenbrand wrote: >>>>> Especially once we hit one of the assertions in >>>>> sanity_check_pinned_pages(), observing follow-up assertions failing >>>>> in other code can give good clues about what went wrong, so use >>>>> VM_WARN_ON_ONCE instead. >>>>> >>>>> While at it, let's just convert all VM_BUG_ON to VM_WARN_ON_ONCE as >>>>> well. Add one comment for the pfn_valid() check. >>>> >>>> It would be a nice touch to add Linus' notes here, with the BUG() history >>>> and all. It answers a FAQ about BUG vs. WARN* that is really nice >>>> to have in the commit log. >>> >>> Perhaps then rather put it somewhere appropriate in Documentation/process/ >>> than a random commit log? >> >> I mean, I documented most of that already in coding-style.rst. :) > > Thanks for the reminder, looks good to me :) > >> The full BUG history is not in there, but not sure if that is really required if ... >> we're not supposed to use it. > > We could put links to the history excursion email (and appropriate older > emails you link in the commit log below) to the References appendix of the > coding-style file, but it's not that critical. Not sure if it's really of value. I mean, whoever questions the rules (for whatever reason ;) ) should probably look at the git log ... -- Cheers, David / dhildenb