On Mon, Jan 26, 2015 at 04:19:06PM +0100, Andrea Arcangeli wrote: > Overall I don't see how we could collapse in readonly vma and where > the bug is for this case, but I may be overlooking something obvious.
I just realized what the problem was... that the "ro" is not the total number of readonly ptes mapped by the pmd,.. because we don't count the none ones as readonly too. It misses a ro increase or equivalent adjustment: if (pte_none(pteval)) { + ro++; if (++none <= khugepaged_max_ptes_none) [..] Andrea -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/