Re: [PATCH] powerpc/mm/hugetlb: Filter out hugepage size not supported by page table layout
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2017-02-19 21:06:08
On Sun, 2017-02-19 at 15:48 +0530, Aneesh Kumar K.V wrote:
+#ifdef CONFIG_PPC_BOOK3S_64
+ /*
+ * We need to make sure that for different page sizes reported by
+ * firmware we only add hugetlb support for page sizes that can be
+ * supported by linux page table layout.
+ * For now we have
+ * Radix: 2M
+ * Hash: 16M and 16G
+ */
+ if (radix_enabled()) {
+ if (mmu_psize != MMU_PAGE_2M)
+ return -EINVAL;
+ } else {
+ if (mmu_psize != MMU_PAGE_16M && mmu_psize != MMU_PAGE_16G)
+ return -EINVAL;
+ }Hash could support others... Same with radix and PUD level pages. Why do we need that ? Won't FW provide separate properties for hash and radix page sizes anyway ? Ben.