powerpc/mm: Handle hypervisor pte insert failure in __hash_page_huge
If the hypervisor gives us an error on a hugepage insert we panic. The
normal page code already handles this by returning an error instead and we end
calling low_hash_fault which will just kill the task if possible.
The patch below does a similar thing for the hugepage case.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index 1995398..c9acd79 100644
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -121,8 +121,15 @@
}
}
- if (unlikely(slot == -2))
- panic("hash_huge_page: pte_insert failed\n");
+ /*
+ * Hypervisor failure. Restore old pte and return -1
+ * similar to __hash_page_*
+ */
+ if (unlikely(slot == -2)) {
+ *ptep = __pte(old_pte);
+ err = -1;
+ goto out;
+ }
new_pte |= (slot << 12) & (_PAGE_F_SECOND | _PAGE_F_GIX);
}