4.9-stable review patch. If anyone has any objections, please let me know.
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From: Kees Cook keescook@chromium.org
Make sure dmesg reports when KPTI is enabled.
Signed-off-by: Kees Cook keescook@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/mm/kaiser.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
--- a/arch/x86/mm/kaiser.c +++ b/arch/x86/mm/kaiser.c @@ -10,6 +10,9 @@ #include <linux/mm.h> #include <linux/uaccess.h>
+#undef pr_fmt +#define pr_fmt(fmt) "Kernel/User page tables isolation: " fmt + #include <asm/kaiser.h> #include <asm/tlbflush.h> /* to verify its kaiser declarations */ #include <asm/pgtable.h> @@ -292,7 +295,7 @@ enable: return;
disable: - pr_info("Kernel/User page tables isolation: disabled\n"); + pr_info("disabled\n");
silent_disable: kaiser_enabled = 0; @@ -352,6 +355,8 @@ void __init kaiser_init(void) kaiser_add_user_map_early(&debug_idt_table, sizeof(gate_desc) * NR_VECTORS, __PAGE_KERNEL); + + pr_info("enabled\n"); }
/* Add a mapping to the shadow mapping, and synchronize the mappings */