>>> Adding Christophe on Cc: >>> >>> Christophe do you know if is_hugepd is true for all hugetlb entries, not >>> just hugepd? >>> >>> On systems without hugepd entries, I guess ptdump skips all hugetlb entries. >>> Sigh! >> >> IIUC, the idea of ptdump_walk_pgd() is to dump page tables even outside >> VMAs (for debugging purposes?). >> >> I cannot convince myself that that's a good idea when only holding the >> mmap lock in read mode, because we can just see page tables getting >> freed concurrently e.g., during concurrent munmap() ... while holding >> the mmap lock in read we may only walk inside VMA boundaries. >> >> That then raises the questions if we're only calling this on special MMs >> (e.g., init_mm) whereby we cannot really see concurrent munmap() and >> where we shouldn't have hugetlb mappings or hugepd entries. >> > > This is going to require a little more thought. > > Since Baolin's patch for stable releases is moving forward, I want to > get the cleanup provided by this patch in ASAP. So, I am going to rebase > this patch on Baolin's with the other fixups. > > Will come back to this cleanup later. Sure, no need to do it all at once (I was just bringing it up while thinking about it). -- Thanks, David / dhildenb
