aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAndi Kleen <ak@suse.de>2008-01-30 13:33:42 +0100
committerIngo Molnar <mingo@elte.hu>2008-01-30 13:33:42 +0100
commit0c42f392767d3592e1cf676857d398ef69be7c9c (patch)
tree0ae79fb0424ed9340ad973bea013251e05553be4
parentb4416a1be86b0c7bdde4e6ba526715c1a055746f (diff)
c_p_a(): do a simple self test at boot
When CONFIG_DEBUG_RODATA is enabled undo the ro mapping and redo it again. This gives some simple testing for change_page_attr(). Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r--arch/x86/Kconfig.debug5
-rw-r--r--arch/x86/mm/init_32.c26
-rw-r--r--arch/x86/mm/init_64.c10
3 files changed, 41 insertions, 0 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index 9bb61e1aed6..38211ff0447 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -204,4 +204,9 @@ config DEBUG_BOOT_PARAMS
help
This option will cause struct boot_params to be exported via debugfs.
+config CPA_DEBUG
+ bool "CPA self test code"
+ help
+ Do change_page_attr self tests at boot.
+
endmenu
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 459b384acda..724a5eff6f3 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -799,6 +799,20 @@ 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: Reverting %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;
@@ -815,6 +829,18 @@ 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
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 8198840c3dc..0fd9d7f7778 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -606,6 +606,16 @@ 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