On 01/03/2019 21:57, Kirill A. Shutemov wrote: > On Wed, Feb 27, 2019 at 05:05:42PM +0000, Steven Price wrote: >> walk_page_range() is going to be allowed to walk page tables other than >> those of user space. For this it needs to know when it has reached a >> 'leaf' entry in the page tables. This information is provided by the >> p?d_large() functions/macros. >> >> For ia64 leaf entries are always at the lowest level, so implement >> stubs returning 0. > > Are you sure about this? I see pte_mkhuge defined for ia64 and Kconfig > contains hugetlb references. > I'm not completely familiar with ia64, but my understanding is that it doesn't have the situation where a page table walk ends early - there is always the full depth of entries. The p?d_huge() functions always return 0. However my understanding is that it does support huge TLB entries, so when populating the TLB a region larger than a standard page can be mapped. I'd definitely welcome review by someone more familiar with ia64 to check my assumptions. Thanks, Steve