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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: fscthbzj7n7dacfip1hxehxtqxuyo974 X-Rspam-User: X-Rspamd-Queue-Id: B2BF514000F X-Rspamd-Server: rspam06 X-HE-Tag: 1675872536-414926 X-HE-Meta: U2FsdGVkX18QsH4mtsqaaEpajB4SEWjnSmPV1mpsgk3ysQzhFpcjgX1iZyxYqkI4UD5DudoVMrKM5/G01IsF3DJYQ1kmuortaCyyPcu1+gRDJjUOfJ7YvEMw0FXO9VjH9VoBF7h/BrdBO/PlzDkCrgSEVL/OswReMZkL7sO6R9l91lawC270lpGixMnu+AAzxayrD948+mzJppSrITZgTUM+gKDKpGf0Ylm1cvVNU8NEtmKVhjW1XYax/KkGUItT5yqYYIaolbgmIX8M7dB9ZAWJacPP9oMVwc4zu2iw9wLsG4IJrEvdopjG8clr607JIy3lOuzev8hGAQrHtx1Ja4VmdQAgcBhaTLRpePBSbH/j9rOD/HXHUDrh9PRSHVusJjgcsCXxw8swSckM1/aFNWX/pCnfLdkx34HoOs3LXK49W9dncfm/YBu1iI6bCPwyo0sFOW9MynaNeNudfmYhP2US54gpIkS26seDpLc8bRHSZU67ntLwVaC1gDCFRep1U+2bqz1/tQKCZSC4qdOnqsk/8lZ+e6wNGMqU6oDLvErizlvq67k1eC3mo2gl57YTivdnerUZdO3Bpbk5p/timAeEHbhxhzOn/8iOWkdwjSFvz4V/CbE0vEq/27cSdIjnvmK7NuOXuDVTqDCyYisUq87iFk+HzlpnGSAQ4XPz7zarfKn/7gd1YLZs462liVlQEfEvcKqqChmGaN17wG7xkaXpSVNHaQn2jzuhoJr+0YU6jek/gwck4+FmSsB7dzEqHqwfWOk9nEfATx3tpfRZz0Yhwo/R4Ho0KiUaacFTAlhpEaoOVjTYHO5ATIpQ2IzkMxjjLfweKCP4rMHoF61XesvoJoRczC+d0RJ1nUz5xsEKxPDCZF1Ik9X70/UHWhU3y/NcmbM+bD+kis6vcDwskpT9zl+xaLU/qML2flq5F8eztLANA2wqtHlkWvI2ifmiOtufABlXYoJyprwPVT0 vXoIaPky Bb7D/nbBLnN3mXDaiVQuZQvBbTJ+TZVi59iC5LSTuYUeiUsK4bdln+d3ePZNz4NQGfbFZ4q4cGBo4QRYnz8FnxVPRDL2x53WSgIML/tYMPaXr0+8/kyJyprqGTCiTf6HCFlX3d7CySALmGbvQegcS+MxLABCTjQqEJ0H1+2+5AJhUEi+r7eM4xfGDefWu2qyGgRUWfXLwFEQYO4m0XjbFv9klH8dkeIfXWKLV7oNoivOY03XqKGILn0Sm74hkmvwqlFSD+E7YFs9XzQWA8RXC8UJNCXtGtVhWb8LeiZ4HJhXsgmmlNngijgw1xp7EXuzXHRZU6leKeC73g2Lc2GJ0UX3A39ScKe4ONbyNPVRX07PXPqC8crg+tkixtg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000018, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Feb 07, 2023 at 03:52:53AM +0000, Matthew Wilcox wrote: > On Mon, Feb 06, 2023 at 06:52:58PM -0800, Luis Chamberlain wrote: > > shmem_writepage() sets up variables typically used *after* a possible > > huge page split. However even if that does happen the address space > > mapping should not change. So it should be safe to set that from > > the beginning. > > Yes, we can get mapping from the folio early. It doesn't change > on split. Great. > > The folio should always be locked from the start as well. It however > > was not clear if the folio address can / should change, as well as > > the first inode. > > > > This commit makes no functional changes other a double check on the > > folio locking which might be superflous. This change should help make > > the subsequent patch easier to review. > > You don't need to check that the folio's locked, That BUG_ON() has been on shmem since linux-history days it's probably best as a separate patch. > and you don't > need to reassign inode after the split. Great! Thanks for this confirmation! Luis