+static void damon_va_mkold(struct mm_struct *mm, unsigned long addr)
+{
+ pte_t *pte = NULL;
+ pmd_t *pmd = NULL;
+ spinlock_t *ptl;
+
I just stumbled over this, sorry for the dumb questions:
a) What do we know about that region we are messing with?
AFAIU, just like follow_pte() and follow_pfn(), follow_invalidate_pte()
should only be called on VM_IO and raw VM_PFNMAP mappings in general
(see the doc of follow_pte()). Do you even know that it's within a
single VMA and that there are no concurrent modifications?
b) Which locks are we holding?
I hope we're holding the mmap lock in read mode at least. Or how are you
making sure there are no concurrent modifications to page tables / VMA
layout ... ?
+ if (follow_invalidate_pte(mm, addr, NULL, &pte, &pmd, &ptl))
--
Thanks,
David / dhildenb
