> > On x86 we just do `char __kfence_pool[KFENCE_POOL_SIZE] ...;` to > > statically allocate the pool. On arm64 this doesn't seem to work > > because static memory doesn't have struct pages? > > Are you using virt_to_page() directly on that statically-allocated > __kfence_pool? If so you'll need to use lm_alias() if so, as is done in > mm/kasan/init.c. > > Anything statically allocated is part of the kernel image address range > rather than the linear/direct map, and doesn't have a valid virt addr, > but its linear map alias does. > > If you enable CONFIG_DEBUG_VIRTUAL you should get warnings if missing > lm_alias() calls. I just checked that on x86 CONFIG_DEBUG_VIRTUAL prints no warnings on our tests. virt_addr_valid() also returns true for addresses belonging to __kfence_pool declared in BSS. Could this be related to x86 mapping the kernel twice?
