From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756088AbcBCXBo (ORCPT ); Wed, 3 Feb 2016 18:01:44 -0500 Received: from pegase1.c-s.fr ([93.17.236.30]:28349 "EHLO mailhub1.si.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758260AbcBCWyE (ORCPT ); Wed, 3 Feb 2016 17:54:04 -0500 Message-Id: <7628f02c47443f08006a45c27ea4c66d251f2ab7.1454538974.git.christophe.leroy@c-s.fr> In-Reply-To: References: From: Christophe Leroy Subject: [PATCH v5 05/23] powerpc32: Fix pte_offset_kernel() to return NULL for bad pages To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Scott Wood Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Wed, 3 Feb 2016 23:53:59 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The fixmap related functions try to map kernel pages that are already mapped through Large TLBs. pte_offset_kernel() has to return NULL for LTLBs, otherwise the caller will try to access level 2 table which doesn't exist Signed-off-by: Christophe Leroy --- v3: new v4: no change v5: no change arch/powerpc/include/asm/nohash/32/pgtable.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h index c82cbf5..e201600 100644 --- a/arch/powerpc/include/asm/nohash/32/pgtable.h +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h @@ -309,7 +309,8 @@ static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry) #define pte_index(address) \ (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) #define pte_offset_kernel(dir, addr) \ - ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr)) + (pmd_bad(*(dir)) ? NULL : (pte_t *)pmd_page_vaddr(*(dir)) + \ + pte_index(addr)) #define pte_offset_map(dir, addr) \ ((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr)) #define pte_unmap(pte) kunmap_atomic(pte) -- 2.1.0