Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755593AbYACPdD (ORCPT ); Thu, 3 Jan 2008 10:33:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754741AbYACPYv (ORCPT ); Thu, 3 Jan 2008 10:24:51 -0500 Received: from cantor2.suse.de ([195.135.220.15]:43008 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751734AbYACPYR (ORCPT ); Thu, 3 Jan 2008 10:24:17 -0500 From: Andi Kleen References: <20080103424.989432000@suse.de> In-Reply-To: <20080103424.989432000@suse.de> To: linux-kernel@vger.kernel.org Subject: [PATCH CPA] [2/28] CPA: Do a simple self test at boot Message-Id: <20080103152416.1D59D14E23@wotan.suse.de> Date: Thu, 3 Jan 2008 16:24:16 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2852 Lines: 94 When CONFIG_DEBUG_RODATA is enabled undo the ro mapping and redo it again. This gives some simple testing for change_page_attr() Optional patch, but I find it useful. Signed-off-by: Andi Kleen --- arch/x86/Kconfig.debug | 5 +++++ arch/x86/mm/init_32.c | 22 ++++++++++++++++++++++ arch/x86/mm/init_64.c | 10 ++++++++++ 3 files changed, 37 insertions(+) Index: linux/arch/x86/mm/init_64.c =================================================================== --- linux.orig/arch/x86/mm/init_64.c +++ linux/arch/x86/mm/init_64.c @@ -596,6 +596,16 @@ void mark_rodata_ro(void) * of who is the culprit. */ global_flush_tlb(); + +#ifdef CONFIG_CPA_DEBUG + printk("Testing CPA: undo %lx-%lx\n", start, end); + change_page_attr_addr(start, (end - start) >> PAGE_SHIFT, PAGE_KERNEL); + global_flush_tlb(); + + printk("Testing CPA: again\n"); + change_page_attr_addr(start, (end - start) >> PAGE_SHIFT, PAGE_KERNEL_RO); + global_flush_tlb(); +#endif } #endif Index: linux/arch/x86/mm/init_32.c =================================================================== --- linux.orig/arch/x86/mm/init_32.c +++ linux/arch/x86/mm/init_32.c @@ -792,6 +792,18 @@ void mark_rodata_ro(void) change_page_attr(virt_to_page(start), size >> PAGE_SHIFT, PAGE_KERNEL_RX); printk("Write protecting the kernel text: %luk\n", size >> 10); + +#ifdef CONFIG_CPA_DEBUG + global_flush_tlb(); + + printk("Testing CPA: undo %lx-%lx\n", start, start+size); + change_page_attr(virt_to_page(start), size>>PAGE_SHIFT, PAGE_KERNEL_EXEC); + global_flush_tlb(); + + printk("Testing CPA: write protecting again\n"); + change_page_attr(virt_to_page(start),size>>PAGE_SHIFT,PAGE_KERNEL_RX); + global_flush_tlb(); +#endif } #endif start += size; @@ -808,6 +820,16 @@ void mark_rodata_ro(void) * of who is the culprit. */ global_flush_tlb(); + +#ifdef CONFIG_CPA_DEBUG + printk("Testing CPA: undo %lx-%lx\n", start, start + size); + change_page_attr(virt_to_page(start), size >> PAGE_SHIFT, PAGE_KERNEL); + global_flush_tlb(); + + printk("Testing CPA: write protecting again\n"); + change_page_attr(virt_to_page(start), size >> PAGE_SHIFT, PAGE_KERNEL_RO); + global_flush_tlb(); +#endif } #endif Index: linux/arch/x86/Kconfig.debug =================================================================== --- linux.orig/arch/x86/Kconfig.debug +++ linux/arch/x86/Kconfig.debug @@ -185,4 +185,9 @@ config DEFAULT_IO_DELAY_TYPE default IO_DELAY_TYPE_NONE endif +config CPA_DEBUG + bool "CPA self test code" + help + Do change_page_attr self tests at boot. + endmenu -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/