On Tue, 13 Aug 2019, Logan Gunthorpe wrote: > On 2019-08-13 12:04 a.m., Greentime Hu wrote: > > > Every architecture with mmu defines their own pfn_valid(). > > Not true. Arm64, for example just uses the generic implementation in > mmzone.h.
arm64 seems to define their own: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/Kconfig#n899 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/mm/init.c#n235 While there are many architectures which have their own pfn_valid(); oddly, almost none of them set HAVE_ARCH_PFN_VALID ? - Paul
