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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: B01E240007 X-Stat-Signature: jyj9g96s69zqdc46witsarayq6ujyr9t X-HE-Tag: 1676402231-152080 X-HE-Meta: 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 9d2hrhot RQBwC65pCDWB/Mk+tR+oeAIOD2V5sWFGE7nu2El9jnOyyeXjQ55QF5Dtv2VV0hXZghZbdY+6WGwTCJNvwLVcuS1h7aWj0w+WLT2Zu5EK4VG0w6eQlPsABnDEhpO6HJiwzb7PdZODB8NgGDvodby7VhdC9YuwmyAgk4qGZjrpoHyStvQkr9Y7TO+SI4uEb74qKIT20mBLMFJoluumUV2YnR2xwB5lwWcmSM/xjSMuS3KWL20saJPT7666PKTbxnyEu1ERj 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: On Tue, Feb 14, 2023 at 10:35:33AM -0800, Sidhartha Kumar wrote: > On 2/14/23 10:23 AM, Deepak R Varma wrote: > > Hello, > > Could someone comment if it is safe to access the page member variable as > > written on line #100 when folio is NULL as returned from the > > It is safe to access the page member variable when folio is NULL because the > offset of page within struct folio is 0.[1] Wow. This is so well thought. Thank you Sidhartha. ./drv > > > [1] https://lore.kernel.org/lkml/Y7h4jsv6jl0XSIsk@casper.infradead.org/T/ > > Thanks, > Sidhartha Kumar > > > __filemap_get_folio() function call? Is this kind of intentional page-fault > > trigger for the system to handle a new/fresh page allocation? > > > > 2 folio = __filemap_get_folio(mapping, index, fgp_flags, gfp); > > 1 if (!folio || xa_is_value(folio)) > > 100 return &folio->page; > > 1 return folio_file_page(folio, index); > > > > The code is part of commit ID c5255b421fd04 > > > > Thank you, > > ./drv > > > > > > >