Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755737AbdIGRh6 (ORCPT ); Thu, 7 Sep 2017 13:37:58 -0400 Received: from mail-it0-f54.google.com ([209.85.214.54]:36744 "EHLO mail-it0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755635AbdIGRhO (ORCPT ); Thu, 7 Sep 2017 13:37:14 -0400 X-Google-Smtp-Source: AOwi7QDOujI+vxj5RJCHod2W762NilLTGjvzzVwhPguEgYvBuuEdK5lyR6ExQWfI5SRc/Aw9VG0t9A== From: Tycho Andersen To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, kernel-hardening@lists.openwall.com, Marco Benatto , Juerg Haefliger , Tycho Andersen , linux-arm-kernel@lists.infradead.org Subject: [PATCH v6 09/11] arm64/mm: disable section/contiguous mappings if XPFO is enabled Date: Thu, 7 Sep 2017 11:36:07 -0600 Message-Id: <20170907173609.22696-10-tycho@docker.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170907173609.22696-1-tycho@docker.com> References: <20170907173609.22696-1-tycho@docker.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1932 Lines: 68 XPFO doesn't support section/contiguous mappings yet, so let's disable it if XPFO is turned on. Thanks to Laura Abbot for the simplification from v5, and Mark Rutland for pointing out we need NO_CONT_MAPPINGS too. CC: linux-arm-kernel@lists.infradead.org Signed-off-by: Tycho Andersen --- arch/arm64/mm/mmu.c | 2 +- include/linux/xpfo.h | 4 ++++ mm/xpfo.c | 6 ++++++ 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index f1eb15e0e864..34bb95303cce 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -420,7 +420,7 @@ static void __init map_mem(pgd_t *pgd) struct memblock_region *reg; int flags = 0; - if (debug_pagealloc_enabled()) + if (debug_pagealloc_enabled() || xpfo_enabled()) flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; /* diff --git a/include/linux/xpfo.h b/include/linux/xpfo.h index d37a06c9d62c..1693af1a0293 100644 --- a/include/linux/xpfo.h +++ b/include/linux/xpfo.h @@ -43,6 +43,8 @@ void xpfo_temp_map(const void *addr, size_t size, void **mapping, void xpfo_temp_unmap(const void *addr, size_t size, void **mapping, size_t mapping_len); +bool xpfo_enabled(void); + #else /* !CONFIG_XPFO */ static inline void xpfo_kmap(void *kaddr, struct page *page) { } @@ -65,6 +67,8 @@ static inline void xpfo_temp_unmap(const void *addr, size_t size, } +static inline bool xpfo_enabled(void) { return false; } + #endif /* CONFIG_XPFO */ #endif /* _LINUX_XPFO_H */ diff --git a/mm/xpfo.c b/mm/xpfo.c index f79075bf7d65..25fba05d01bd 100644 --- a/mm/xpfo.c +++ b/mm/xpfo.c @@ -70,6 +70,12 @@ struct page_ext_operations page_xpfo_ops = { .init = init_xpfo, }; +bool __init xpfo_enabled(void) +{ + return !xpfo_disabled; +} +EXPORT_SYMBOL(xpfo_enabled); + static inline struct xpfo *lookup_xpfo(struct page *page) { struct page_ext *page_ext = lookup_page_ext(page); -- 2.11.0