Merge tag 'v4.14-rc2' into next-general

Linux 4.14-rc2

Sync to v4.14-rc2 for security subsystem developers to track.

1 files changed, 23 insertions, 2 deletions

diff --git a/arch/x86/include/asm/mmu.h b/arch/x86/include/asm/mmu.h
index 79b647a7ebd0..bb8c597c2248 100644
--- a/arch/x86/include/asm/mmu.h
+++ b/arch/x86/include/asm/mmu.h
@@ -3,12 +3,28 @@
 
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
+#include <linux/atomic.h>
 
 /*
- * The x86 doesn't have a mmu context, but
- * we put the segment information here.
+ * x86 has arch-specific MMU state beyond what lives in mm_struct.
  */
 typedef struct {
+	/*
+	 * ctx_id uniquely identifies this mm_struct.  A ctx_id will never
+	 * be reused, and zero is not a valid ctx_id.
+	 */
+	u64 ctx_id;
+
+	/*
+	 * Any code that needs to do any sort of TLB flushing for this
+	 * mm will first make its changes to the page tables, then
+	 * increment tlb_gen, then flush.  This lets the low-level
+	 * flushing code keep track of what needs flushing.
+	 *
+	 * This is not used on Xen PV.
+	 */
+	atomic64_t tlb_gen;
+
 #ifdef CONFIG_MODIFY_LDT_SYSCALL
 	struct ldt_struct *ldt;
 #endif
@@ -37,6 +53,11 @@ typedef struct {
 #endif
 } mm_context_t;
 
+#define INIT_MM_CONTEXT(mm)						\
+	.context = {							\
+		.ctx_id = 1,						\
+	}
+
 void leave_mm(int cpu);
 
 #endif /* _ASM_X86_MMU_H */