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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Jason Gunthorpe , John Hubbard , Peter Xu References: <20250604140544.688711-1-david@redhat.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: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: OnuotjATmid9XwokoaITypBVbmPIozBCxJyBnlrGhbU_1749197417 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: rspam10 X-Rspamd-Queue-Id: 3957B180009 X-Stat-Signature: 6so15yph8xkkbska4nhbpuzwfeuukt7e X-Rspam-User: X-HE-Tag: 1749197420-296273 X-HE-Meta: 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 fqcfagG1 F4+ZmCkjTwyK7RgU87ld47g3cqz8N3go1y5gEuS8gWdPzjuvICTRK/SwwUGCLtuig7lTMzKdZHIc77QzptcMmueT/7c3TCt+N4KR47CoCQ7LkqnXKRKSWEt+NI4GRIu800QyYKlxZ+dKvelo26KAm0E5BoBLuEycZ3ocSs0I1KgHVqMBzbYbD1tXlrm6JK3UdJALHgmzlfH6+CC5erLbE0l8g7vAOnLDqh6n8V/3AhVsc01hVZGr8IgJq9iUR+DTSaicbMOehJfWNoSNUYgOuzyhBSK1YA/sAsw8RieJkGPQf3hylT+s5ckecTtK1naPqkUlu+mYJIcoYwWh/dg7InTVvL9x2WB1TH0npu7PwPmWZ1TBryGhumlqbAmFTej2RXoZvAQXK/UkZqdI34xr2ARb7HOKoEiG6X6Sm64iqneoZgeEBZnQsTLKPmTE/C8JcWYN3hTjevM7ocmw= 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 09:10, Michal Hocko wrote: > On Wed 04-06-25 16:05:44, 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. >> >> We have to introduce VM_WARN_ON_ONCE_VMA() to make that fly. >> >> Drop the BUG_ON after mmap_read_lock_killable(), if that ever returns >> something > 0 we're in bigger trouble. Convert the other BUG_ON's into >> VM_WARN_ON_ONCE as well, they are in a similar domain "should never >> happen", but more reasonable to check for during early testing. > > The patch itself makes sense and I think it is good time to revisit old > discussion [1] and finally drop VM_BUG_ON altogether and replace it by > VM_WARN_ON which could be still a useful debugging aid. Yes. I think we should check all cases if they are really relevant (and are clear), and also handle BUG_ON on the way. ... essentially what I did in this patch :) Thanks! -- Cheers, David / dhildenb