Merge commit 'ftrace/auto-ftrace-next'

Conflicts:

	kernel/module.c

3 files changed, 71 insertions, 0 deletions

diff --git a/include/asm-x86/ftrace.h b/include/asm-x86/ftrace.h
index be0e004ad148..1bb6f9bbe1ab 100644
--- a/include/asm-x86/ftrace.h
+++ b/include/asm-x86/ftrace.h
@@ -7,6 +7,16 @@
 
 #ifndef __ASSEMBLY__
 extern void mcount(void);
+
+static inline unsigned long ftrace_call_adjust(unsigned long addr)
+{
+	/*
+	 * call mcount is "e8 <4 byte offset>"
+	 * The addr points to the 4 byte offset and the caller of this
+	 * function wants the pointer to e8. Simply subtract one.
+	 */
+	return addr - 1;
+}
 #endif
 
 #endif /* CONFIG_FTRACE */
diff --git a/include/asm-x86/irqflags.h b/include/asm-x86/irqflags.h
index 424acb48cd61..13980f82fd69 100644
--- a/include/asm-x86/irqflags.h
+++ b/include/asm-x86/irqflags.h
@@ -51,6 +51,61 @@ static inline void native_halt(void)
 
 #endif
 
+#ifdef CONFIG_X86_64
+/*
+ * Only returns from a trap or exception to a NMI context (intra-privilege
+ * level near return) to the same SS and CS segments. Should be used
+ * upon trap or exception return when nested over a NMI context so no iret is
+ * issued. It takes care of modifying the eflags, rsp and returning to the
+ * previous function.
+ *
+ * The stack, at that point, looks like :
+ *
+ * 0(rsp)  RIP
+ * 8(rsp)  CS
+ * 16(rsp) EFLAGS
+ * 24(rsp) RSP
+ * 32(rsp) SS
+ *
+ * Upon execution :
+ * Copy EIP to the top of the return stack
+ * Update top of return stack address
+ * Pop eflags into the eflags register
+ * Make the return stack current
+ * Near return (popping the return address from the return stack)
+ */
+#define NATIVE_INTERRUPT_RETURN_NMI_SAFE	pushq %rax;		\
+						movq %rsp, %rax;	\
+						movq 24+8(%rax), %rsp;	\
+						pushq 0+8(%rax);	\
+						pushq 16+8(%rax);	\
+						movq (%rax), %rax;	\
+						popfq;			\
+						ret
+#else
+/*
+ * Protected mode only, no V8086. Implies that protected mode must
+ * be entered before NMIs or MCEs are enabled. Only returns from a trap or
+ * exception to a NMI context (intra-privilege level far return). Should be used
+ * upon trap or exception return when nested over a NMI context so no iret is
+ * issued.
+ *
+ * The stack, at that point, looks like :
+ *
+ * 0(esp) EIP
+ * 4(esp) CS
+ * 8(esp) EFLAGS
+ *
+ * Upon execution :
+ * Copy the stack eflags to top of stack
+ * Pop eflags into the eflags register
+ * Far return: pop EIP and CS into their register, and additionally pop EFLAGS.
+ */
+#define NATIVE_INTERRUPT_RETURN_NMI_SAFE	pushl 8(%esp);	\
+						popfl;		\
+						lret $4
+#endif
+
 #ifdef CONFIG_PARAVIRT
 #include <asm/paravirt.h>
 #else
@@ -109,6 +164,7 @@ static inline unsigned long __raw_local_irq_save(void)
 
 #define ENABLE_INTERRUPTS(x)	sti
 #define DISABLE_INTERRUPTS(x)	cli
+#define INTERRUPT_RETURN_NMI_SAFE	NATIVE_INTERRUPT_RETURN_NMI_SAFE
 
 #ifdef CONFIG_X86_64
 #define SWAPGS	swapgs
diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index 8d6ae2f760d0..d5808653db92 100644
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -175,6 +175,7 @@ struct pv_cpu_ops {
 	/* Normal iret.  Jump to this with the standard iret stack
 	   frame set up. */
 	void (*iret)(void);
+	void (*nmi_return)(void);
 
 	void (*swapgs)(void);
 
@@ -1577,6 +1578,10 @@ static inline unsigned long __raw_local_irq_save(void)
 	PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_iret), CLBR_NONE,	\
 		  jmp PARA_INDIRECT(pv_cpu_ops+PV_CPU_iret))
 
+#define INTERRUPT_RETURN_NMI_SAFE					\
+	PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_nmi_return), CLBR_NONE,	\
+		  jmp *%cs:pv_cpu_ops+PV_CPU_nmi_return)
+
 #define DISABLE_INTERRUPTS(clobbers)					\
 	PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_disable), clobbers, \
 		  PV_SAVE_REGS;						\