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 NzHE7oDJ 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 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 2025-09-02 at 22:06 +1000, Jason Gunthorpe wrote... > On Tue, Sep 02, 2025 at 03:14:20PM +1000, Alistair Popple wrote: > > Prior to aed877c2b425 ("device/dax: properly refcount device dax pages > > when mapping") ZONE_DEVICE pages were not fully reference counted when > > mapped into user page tables. Instead GUP would take a reference on the > > associated pgmap to ensure the results of pfn_to_page() remained valid. > > > > This is no longer required and most of the code was removed by > > fd2825b0760a ("mm/gup: remove pXX_devmap usage from get_user_pages()"). > > Finish cleaning this up by removing the dead calls to put_dev_pagemap() > > and the temporary context struct. > > > > Signed-off-by: Alistair Popple > > --- > > mm/gup.c | 67 ++++++++++++++++++++++---------------------------------- > > 1 file changed, 26 insertions(+), 41 deletions(-) > > Reviewed-by: Jason Gunthorpe > > Yay! This never made alot of sense :\ Yeah. We could probably get rid of the pagemap refcounting entirely, but that's on my backlog for now as it doesn't seem super important. > Jason