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a=0v93pcGMeb4zWV5x07AA:9 a=CjuIK1q_8ugA:10 cc=ntf awl=host:13565 On Mon, Jul 07, 2025 at 02:27:01PM +0200, David Hildenbrand wrote: > IIRC, MAP_ANON |MAP_SHARED would have done a shmem_zero_setup(). > > mm/mmap.c still has the comment "mmap_region() will call shmem_zero_setup() > to create a file". Correct. > > I think this was moved to __mmap_new_vma(). > > Is there any (error) path where we could not call that by accident? No. Shared means there's a file. This also would mean we've been kernel NULL pointer dereferencing since 2019 btw when this change was made. I don't recall the reports... :>) I think people get confused because MAP_SHARED | MAP_ANON makes people think there won't be a file. Our terminology sucks... > > -- > Cheers, > > David / dhildenb >