> The bpf_map->ops->map_mmap callback invoked by bpf_map_mmap() can be set to > one of ringbuf_map_mmap_kern(), ringbuf_map_mmap_user(), array_map_mmap() > or arena_map_mmap(). > > It is convention in mm to mark mappings whose pages the kernel manages > itself with VM_MIXEDMAP, so core mm knows not to treat them as ordinary > page cache or anonymous memory. > > The map_mmap callbacks ringbuf_map_mmap_kern() and ringbuf_map_mmap_user() > use remap_vmalloc_range(), which ultimately invokes vm_insert_page() and so > marks the ranges VM_MIXEDMAP, and array_map_mmap() sets VM_MIXEDMAP > explicitly. > > However, the exception to this is arena_map_mmap(), which doesn't set the > flag. > [ ... ] > in bpf_map_mmap(). > > Reviewed-by: Emil Tsalapatis <[email protected]> > Reviewed-by: Suren Baghdasaryan <[email protected]> > Signed-off-by: Lorenzo Stoakes (ARM) <[email protected]>
Sashiko has reviewed this patch and found no issues. It looks great! -- Sashiko AI review ยท https://sashiko.dev/#/patchset/20261009-b4-mmap-prepare-vma-flag-sanify-v5-0-923b70125...@kernel.org?part=13
