Merge tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull objtool updates from Ingo Molnar:

 - Mark arch_cpu_idle_dead() __noreturn, make all architectures &
   drivers that did this inconsistently follow this new, common
   convention, and fix all the fallout that objtool can now detect
   statically

 - Fix/improve the ORC unwinder becoming unreliable due to
   UNWIND_HINT_EMPTY ambiguity, split it into UNWIND_HINT_END_OF_STACK
   and UNWIND_HINT_UNDEFINED to resolve it

 - Fix noinstr violations in the KCSAN code and the lkdtm/stackleak code

 - Generate ORC data for __pfx code

 - Add more __noreturn annotations to various kernel startup/shutdown
   and panic functions

 - Misc improvements & fixes

* tag 'objtool-core-2023-04-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  x86/hyperv: Mark hv_ghcb_terminate() as noreturn
  scsi: message: fusion: Mark mpt_halt_firmware() __noreturn
  x86/cpu: Mark {hlt,resume}_play_dead() __noreturn
  btrfs: Mark btrfs_assertfail() __noreturn
  objtool: Include weak functions in global_noreturns check
  cpu: Mark nmi_panic_self_stop() __noreturn
  cpu: Mark panic_smp_self_stop() __noreturn
  arm64/cpu: Mark cpu_park_loop() and friends __noreturn
  x86/head: Mark *_start_kernel() __noreturn
  init: Mark start_kernel() __noreturn
  init: Mark [arch_call_]rest_init() __noreturn
  objtool: Generate ORC data for __pfx code
  x86/linkage: Fix padding for typed functions
  objtool: Separate prefix code from stack validation code
  objtool: Remove superfluous dead_end_function() check
  objtool: Add symbol iteration helpers
  objtool: Add WARN_INSN()
  scripts/objdump-func: Support multiple functions
  context_tracking: Fix KCSAN noinstr violation
  objtool: Add stackleak instrumentation to uaccess safe list
  ...

24 files changed, 92 insertions, 85 deletions

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 1b1136c024df..f31e286c2977 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -205,7 +205,7 @@ syscall_return_via_sysret:
 	 */
 	movq	%rsp, %rdi
 	movq	PER_CPU_VAR(cpu_tss_rw + TSS_sp0), %rsp
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 
 	pushq	RSP-RDI(%rdi)	/* RSP */
 	pushq	(%rdi)		/* RDI */
@@ -286,7 +286,7 @@ SYM_FUNC_END(__switch_to_asm)
 .pushsection .text, "ax"
 	__FUNC_ALIGN
 SYM_CODE_START_NOALIGN(ret_from_fork)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR // copy_thread
 	CALL_DEPTH_ACCOUNT
 	movq	%rax, %rdi
@@ -303,7 +303,7 @@ SYM_CODE_START_NOALIGN(ret_from_fork)
 
 1:
 	/* kernel thread */
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	movq	%r12, %rdi
 	CALL_NOSPEC rbx
 	/*
@@ -388,9 +388,9 @@ SYM_CODE_START(\asmsym)
 
 	.if \vector == X86_TRAP_BP
 		/* #BP advances %rip to the next instruction */
-		UNWIND_HINT_IRET_REGS offset=\has_error_code*8 signal=0
+		UNWIND_HINT_IRET_ENTRY offset=\has_error_code*8 signal=0
 	.else
-		UNWIND_HINT_IRET_REGS offset=\has_error_code*8
+		UNWIND_HINT_IRET_ENTRY offset=\has_error_code*8
 	.endif
 
 	ENDBR
@@ -461,7 +461,7 @@ SYM_CODE_END(\asmsym)
  */
 .macro idtentry_mce_db vector asmsym cfunc
 SYM_CODE_START(\asmsym)
-	UNWIND_HINT_IRET_REGS
+	UNWIND_HINT_IRET_ENTRY
 	ENDBR
 	ASM_CLAC
 	cld
@@ -518,7 +518,7 @@ SYM_CODE_END(\asmsym)
  */
 .macro idtentry_vc vector asmsym cfunc
 SYM_CODE_START(\asmsym)
-	UNWIND_HINT_IRET_REGS
+	UNWIND_HINT_IRET_ENTRY
 	ENDBR
 	ASM_CLAC
 	cld
@@ -582,7 +582,7 @@ SYM_CODE_END(\asmsym)
  */
 .macro idtentry_df vector asmsym cfunc
 SYM_CODE_START(\asmsym)
-	UNWIND_HINT_IRET_REGS offset=8
+	UNWIND_HINT_IRET_ENTRY offset=8
 	ENDBR
 	ASM_CLAC
 	cld
@@ -643,7 +643,7 @@ SYM_INNER_LABEL(swapgs_restore_regs_and_return_to_usermode, SYM_L_GLOBAL)
 	 */
 	movq	%rsp, %rdi
 	movq	PER_CPU_VAR(cpu_tss_rw + TSS_sp0), %rsp
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 
 	/* Copy the IRET frame to the trampoline stack. */
 	pushq	6*8(%rdi)	/* SS */
@@ -869,7 +869,7 @@ SYM_CODE_END(exc_xen_hypervisor_callback)
  */
 	__FUNC_ALIGN
 SYM_CODE_START_NOALIGN(xen_failsafe_callback)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ENDBR
 	movl	%ds, %ecx
 	cmpw	%cx, 0x10(%rsp)
@@ -1107,7 +1107,7 @@ SYM_CODE_START(error_entry)
 	FENCE_SWAPGS_KERNEL_ENTRY
 	CALL_DEPTH_ACCOUNT
 	leaq	8(%rsp), %rax			/* return pt_regs pointer */
-	ANNOTATE_UNRET_END
+	VALIDATE_UNRET_END
 	RET
 
 .Lbstep_iret:
@@ -1153,7 +1153,7 @@ SYM_CODE_END(error_return)
  *	      when PAGE_TABLE_ISOLATION is in use.  Do not clobber.
  */
 SYM_CODE_START(asm_exc_nmi)
-	UNWIND_HINT_IRET_REGS
+	UNWIND_HINT_IRET_ENTRY
 	ENDBR
 
 	/*
@@ -1520,7 +1520,7 @@ SYM_CODE_END(asm_exc_nmi)
  * MSRs to fully disable 32-bit SYSCALL.
  */
 SYM_CODE_START(ignore_sysret)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ENDBR
 	mov	$-ENOSYS, %eax
 	sysretl
diff --git a/arch/x86/hyperv/ivm.c b/arch/x86/hyperv/ivm.c
index 127d5b7b63de..cc92388b7a99 100644
--- a/arch/x86/hyperv/ivm.c
+++ b/arch/x86/hyperv/ivm.c
@@ -129,7 +129,7 @@ static enum es_result hv_ghcb_hv_call(struct ghcb *ghcb, u64 exit_code,
 		return ES_OK;
 }
 
-void hv_ghcb_terminate(unsigned int set, unsigned int reason)
+void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason)
 {
 	u64 val = GHCB_MSR_TERM_REQ;
 
diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h
index dd9b8118f784..0953aa32a324 100644
--- a/arch/x86/include/asm/linkage.h
+++ b/arch/x86/include/asm/linkage.h
@@ -99,7 +99,7 @@
 
 /* SYM_TYPED_FUNC_START -- use for indirectly called globals, w/ CFI type */
 #define SYM_TYPED_FUNC_START(name)				\
-	SYM_TYPED_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)	\
+	SYM_TYPED_START(name, SYM_L_GLOBAL, SYM_F_ALIGN)	\
 	ENDBR
 
 /* SYM_FUNC_START -- use for global functions */
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index b445e252aa83..49bb4f2bd300 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -228,7 +228,7 @@ int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry);
 void hv_ghcb_msr_write(u64 msr, u64 value);
 void hv_ghcb_msr_read(u64 msr, u64 *value);
 bool hv_ghcb_negotiate_protocol(void);
-void hv_ghcb_terminate(unsigned int set, unsigned int reason);
+void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason);
 void hv_vtom_init(void);
 #else
 static inline void hv_ghcb_msr_write(u64 msr, u64 value) {}
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 3ef70e54a858..edb2b0cb8efe 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -194,9 +194,9 @@
  * builds.
  */
 .macro ANNOTATE_RETPOLINE_SAFE
-	.Lannotate_\@:
+.Lhere_\@:
 	.pushsection .discard.retpoline_safe
-	_ASM_PTR .Lannotate_\@
+	.long .Lhere_\@ - .
 	.popsection
 .endm
 
@@ -210,8 +210,8 @@
  * Abuse ANNOTATE_RETPOLINE_SAFE on a NOP to indicate UNRET_END, should
  * eventually turn into it's own annotation.
  */
-.macro ANNOTATE_UNRET_END
-#ifdef CONFIG_DEBUG_ENTRY
+.macro VALIDATE_UNRET_END
+#if defined(CONFIG_NOINSTR_VALIDATION) && defined(CONFIG_CPU_UNRET_ENTRY)
 	ANNOTATE_RETPOLINE_SAFE
 	nop
 #endif
@@ -286,7 +286,7 @@
 .macro UNTRAIN_RET
 #if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_IBPB_ENTRY) || \
 	defined(CONFIG_CALL_DEPTH_TRACKING)
-	ANNOTATE_UNRET_END
+	VALIDATE_UNRET_END
 	ALTERNATIVE_3 "",						\
 		      CALL_ZEN_UNTRAIN_RET, X86_FEATURE_UNRET,		\
 		      "call entry_ibpb", X86_FEATURE_ENTRY_IBPB,	\
@@ -297,7 +297,7 @@
 .macro UNTRAIN_RET_FROM_CALL
 #if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_IBPB_ENTRY) || \
 	defined(CONFIG_CALL_DEPTH_TRACKING)
-	ANNOTATE_UNRET_END
+	VALIDATE_UNRET_END
 	ALTERNATIVE_3 "",						\
 		      CALL_ZEN_UNTRAIN_RET, X86_FEATURE_UNRET,		\
 		      "call entry_ibpb", X86_FEATURE_ENTRY_IBPB,	\
@@ -318,7 +318,7 @@
 #define ANNOTATE_RETPOLINE_SAFE					\
 	"999:\n\t"						\
 	".pushsection .discard.retpoline_safe\n\t"		\
-	_ASM_PTR " 999b\n\t"					\
+	".long 999b - .\n\t"					\
 	".popsection\n\t"
 
 typedef u8 retpoline_thunk_t[RETPOLINE_THUNK_SIZE];
diff --git a/arch/x86/include/asm/orc_types.h b/arch/x86/include/asm/orc_types.h
index 1343a62106de..46d7e06763c9 100644
--- a/arch/x86/include/asm/orc_types.h
+++ b/arch/x86/include/asm/orc_types.h
@@ -39,6 +39,12 @@
 #define ORC_REG_SP_INDIRECT		9
 #define ORC_REG_MAX			15
 
+#define ORC_TYPE_UNDEFINED		0
+#define ORC_TYPE_END_OF_STACK		1
+#define ORC_TYPE_CALL			2
+#define ORC_TYPE_REGS			3
+#define ORC_TYPE_REGS_PARTIAL		4
+
 #ifndef __ASSEMBLY__
 #include <asm/byteorder.h>
 
@@ -56,16 +62,14 @@ struct orc_entry {
 #if defined(__LITTLE_ENDIAN_BITFIELD)
 	unsigned	sp_reg:4;
 	unsigned	bp_reg:4;
-	unsigned	type:2;
+	unsigned	type:3;
 	unsigned	signal:1;
-	unsigned	end:1;
 #elif defined(__BIG_ENDIAN_BITFIELD)
 	unsigned	bp_reg:4;
 	unsigned	sp_reg:4;
 	unsigned	unused:4;
-	unsigned	end:1;
 	unsigned	signal:1;
-	unsigned	type:2;
+	unsigned	type:3;
 #endif
 } __packed;
 
diff --git a/arch/x86/include/asm/reboot.h b/arch/x86/include/asm/reboot.h
index bc5b4d788c08..9177b4354c3f 100644
--- a/arch/x86/include/asm/reboot.h
+++ b/arch/x86/include/asm/reboot.h
@@ -28,7 +28,6 @@ void __noreturn machine_real_restart(unsigned int type);
 void cpu_emergency_disable_virtualization(void);
 
 typedef void (*nmi_shootdown_cb)(int, struct pt_regs*);
-void nmi_panic_self_stop(struct pt_regs *regs);
 void nmi_shootdown_cpus(nmi_shootdown_cb callback);
 void run_crash_ipi_callback(struct pt_regs *regs);
 
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index f37cbff7354c..f3495623ac99 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -125,11 +125,11 @@ void clear_bss(void);
 
 #ifdef __i386__
 
-asmlinkage void __init i386_start_kernel(void);
+asmlinkage void __init __noreturn i386_start_kernel(void);
 
 #else
-asmlinkage void __init x86_64_start_kernel(char *real_mode);
-asmlinkage void __init x86_64_start_reservations(char *real_mode_data);
+asmlinkage void __init __noreturn x86_64_start_kernel(char *real_mode);
+asmlinkage void __init __noreturn x86_64_start_reservations(char *real_mode_data);
 
 #endif /* __i386__ */
 #endif /* _SETUP */
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
index bf2c51df9e0b..9fa795102b93 100644
--- a/arch/x86/include/asm/smp.h
+++ b/arch/x86/include/asm/smp.h
@@ -93,9 +93,10 @@ static inline void __cpu_die(unsigned int cpu)
 	smp_ops.cpu_die(cpu);
 }
 
-static inline void play_dead(void)
+static inline void __noreturn play_dead(void)
 {
 	smp_ops.play_dead();
+	BUG();
 }
 
 static inline void smp_send_reschedule(int cpu)
@@ -124,7 +125,7 @@ int native_cpu_up(unsigned int cpunum, struct task_struct *tidle);
 int native_cpu_disable(void);
 int common_cpu_die(unsigned int cpu);
 void native_cpu_die(unsigned int cpu);
-void hlt_play_dead(void);
+void __noreturn hlt_play_dead(void);
 void native_play_dead(void);
 void play_dead_common(void);
 void wbinvd_on_cpu(int cpu);
diff --git a/arch/x86/include/asm/unwind_hints.h b/arch/x86/include/asm/unwind_hints.h
index e7c71750b309..01cb9692b160 100644
--- a/arch/x86/include/asm/unwind_hints.h
+++ b/arch/x86/include/asm/unwind_hints.h
@@ -7,12 +7,17 @@
 
 #ifdef __ASSEMBLY__
 
-.macro UNWIND_HINT_EMPTY
-	UNWIND_HINT type=UNWIND_HINT_TYPE_CALL end=1
+.macro UNWIND_HINT_END_OF_STACK
+	UNWIND_HINT type=UNWIND_HINT_TYPE_END_OF_STACK
+.endm
+
+.macro UNWIND_HINT_UNDEFINED
+	UNWIND_HINT type=UNWIND_HINT_TYPE_UNDEFINED
 .endm
 
 .macro UNWIND_HINT_ENTRY
-	UNWIND_HINT type=UNWIND_HINT_TYPE_ENTRY end=1
+	VALIDATE_UNRET_BEGIN
+	UNWIND_HINT_END_OF_STACK
 .endm
 
 .macro UNWIND_HINT_REGS base=%rsp offset=0 indirect=0 extra=1 partial=0 signal=1
@@ -52,6 +57,11 @@
 	UNWIND_HINT_REGS base=\base offset=\offset partial=1 signal=\signal
 .endm
 
+.macro UNWIND_HINT_IRET_ENTRY base=%rsp offset=0 signal=1
+	VALIDATE_UNRET_BEGIN
+	UNWIND_HINT_IRET_REGS base=\base offset=\offset signal=\signal
+.endm
+
 .macro UNWIND_HINT_FUNC
 	UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=8 type=UNWIND_HINT_TYPE_FUNC
 .endm
@@ -67,7 +77,7 @@
 #else
 
 #define UNWIND_HINT_FUNC \
-	UNWIND_HINT(ORC_REG_SP, 8, UNWIND_HINT_TYPE_FUNC, 0, 0)
+	UNWIND_HINT(UNWIND_HINT_TYPE_FUNC, ORC_REG_SP, 8, 0)
 
 #endif /* __ASSEMBLY__ */
 
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
index 970d8445fdc4..b8c720b5dab2 100644
--- a/arch/x86/kernel/ftrace_64.S
+++ b/arch/x86/kernel/ftrace_64.S
@@ -346,7 +346,7 @@ STACK_FRAME_NON_STANDARD_FP(__fentry__)
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 SYM_CODE_START(return_to_handler)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ANNOTATE_NOENDBR
 	subq  $16, %rsp
 
diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index ec6fefbfd3c0..10c27b4261eb 100644
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -29,7 +29,7 @@ static void __init i386_default_early_setup(void)
 	x86_init.mpparse.setup_ioapic_ids = setup_ioapic_ids_from_mpc;
 }
 
-asmlinkage __visible void __init i386_start_kernel(void)
+asmlinkage __visible void __init __noreturn i386_start_kernel(void)
 {
 	/* Make sure IDT is set up before any exception happens */
 	idt_setup_early_handler();
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 387e4b12e823..49f7629b17f7 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -471,7 +471,7 @@ static void __init copy_bootdata(char *real_mode_data)
 	sme_unmap_bootdata(real_mode_data);
 }
 
-asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
+asmlinkage __visible void __init __noreturn x86_64_start_kernel(char * real_mode_data)
 {
 	/*
 	 * Build-time sanity checks on the kernel image and module
@@ -537,7 +537,7 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
 	x86_64_start_reservations(real_mode_data);
 }
 
-void __init x86_64_start_reservations(char *real_mode_data)
+void __init __noreturn x86_64_start_reservations(char *real_mode_data)
 {
 	/* version is always not zero if it is copied */
 	if (!boot_params.hdr.version)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 6a8238702eab..a5df3e994f04 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -42,7 +42,7 @@ L3_START_KERNEL = pud_index(__START_KERNEL_map)
 	__HEAD
 	.code64
 SYM_CODE_START_NOALIGN(startup_64)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	/*
 	 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 0,
 	 * and someone has loaded an identity mapped page table
@@ -97,7 +97,7 @@ SYM_CODE_START_NOALIGN(startup_64)
 	lretq
 
 .Lon_kernel_cs:
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 
 	/* Sanitize CPU configuration */
 	call verify_cpu
@@ -119,7 +119,7 @@ SYM_CODE_START_NOALIGN(startup_64)
 SYM_CODE_END(startup_64)
 
 SYM_CODE_START(secondary_startup_64)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR
 	/*
 	 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 0,
@@ -148,7 +148,7 @@ SYM_CODE_START(secondary_startup_64)
 	 * verify_cpu() above to make sure NX is enabled.
 	 */
 SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR
 
 	/*
@@ -230,7 +230,7 @@ SYM_INNER_LABEL(secondary_startup_64_no_verify, SYM_L_GLOBAL)
 	ANNOTATE_RETPOLINE_SAFE
 	jmp	*%rax
 1:
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR // above
 
 #ifdef CONFIG_SMP
@@ -383,7 +383,7 @@ SYM_CODE_END(secondary_startup_64)
  */
 SYM_CODE_START(start_cpu0)
 	ANNOTATE_NOENDBR
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 
 	/* Find the idle task stack */
 	movq	PER_CPU_VAR(pcpu_hot) + X86_current_task, %rcx
@@ -406,8 +406,6 @@ SYM_CODE_START_NOALIGN(vc_boot_ghcb)
 	UNWIND_HINT_IRET_REGS offset=8
 	ENDBR
 
-	ANNOTATE_UNRET_END
-
 	/* Build pt_regs */
 	PUSH_AND_CLEAR_REGS
 
@@ -460,7 +458,6 @@ SYM_CODE_END(early_idt_handler_array)
 
 SYM_CODE_START_LOCAL(early_idt_handler_common)
 	UNWIND_HINT_IRET_REGS offset=16
-	ANNOTATE_UNRET_END
 	/*
 	 * The stack is the hardware frame, an error code or zero, and the
 	 * vector number.
@@ -510,8 +507,6 @@ SYM_CODE_START_NOALIGN(vc_no_ghcb)
 	UNWIND_HINT_IRET_REGS offset=8
 	ENDBR
 
-	ANNOTATE_UNRET_END
-
 	/* Build pt_regs */
 	PUSH_AND_CLEAR_REGS
 
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 50d950771371..dac41a0072ea 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -5,6 +5,7 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
+#include <linux/cpu.h>
 #include <linux/prctl.h>
 #include <linux/slab.h>
 #include <linux/sched.h>
@@ -721,7 +722,7 @@ static bool x86_idle_set(void)
 }
 
 #ifndef CONFIG_SMP
-static inline void play_dead(void)
+static inline void __noreturn play_dead(void)
 {
 	BUG();
 }
@@ -733,7 +734,7 @@ void arch_cpu_idle_enter(void)
 	local_touch_nmi();
 }
 
-void arch_cpu_idle_dead(void)
+void __noreturn arch_cpu_idle_dead(void)
 {
 	play_dead();
 }
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index d03c551defcc..3adbe97015c1 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -920,7 +920,7 @@ void run_crash_ipi_callback(struct pt_regs *regs)
 }
 
 /* Override the weak function in kernel/panic.c */
-void nmi_panic_self_stop(struct pt_regs *regs)
+void __noreturn nmi_panic_self_stop(struct pt_regs *regs)
 {
 	while (1) {
 		/* If no CPU is preparing crash dump, we simply loop here. */
diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
index 4a73351f87f8..56cab1bb25f5 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S
@@ -43,7 +43,7 @@
 	.code64
 SYM_CODE_START_NOALIGN(relocate_range)
 SYM_CODE_START_NOALIGN(relocate_kernel)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR
 	/*
 	 * %rdi indirection_page
@@ -113,7 +113,7 @@ SYM_CODE_START_NOALIGN(relocate_kernel)
 SYM_CODE_END(relocate_kernel)
 
 SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	/* set return address to 0 if not preserving context */
 	pushq	$0
 	/* store the start address on the stack */
@@ -231,7 +231,7 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
 SYM_CODE_END(identity_mapped)
 
 SYM_CODE_START_LOCAL_NOALIGN(virtual_mapped)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR // RET target, above
 	movq	RSP(%r8), %rsp
 	movq	CR4(%r8), %rax
@@ -256,8 +256,8 @@ SYM_CODE_END(virtual_mapped)
 
 	/* Do the copies */
 SYM_CODE_START_LOCAL_NOALIGN(swap_pages)
-	UNWIND_HINT_EMPTY
-	movq	%rdi, %rcx 	/* Put the page_list in %rcx */
+	UNWIND_HINT_END_OF_STACK
+	movq	%rdi, %rcx	/* Put the page_list in %rcx */
 	xorl	%edi, %edi
 	xorl	%esi, %esi
 	jmp	1f
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 851477f7d728..352f0ce1ece4 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1824,7 +1824,7 @@ static inline void mwait_play_dead(void)
 	}
 }
 
-void hlt_play_dead(void)
+void __noreturn hlt_play_dead(void)
 {
 	if (__this_cpu_read(cpu_info.x86) >= 4)
 		wbinvd();
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 37307b40f8da..3ac50b7298d1 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -133,7 +133,7 @@ static struct orc_entry null_orc_entry = {
 	.sp_offset = sizeof(long),
 	.sp_reg = ORC_REG_SP,
 	.bp_reg = ORC_REG_UNDEFINED,
-	.type = UNWIND_HINT_TYPE_CALL
+	.type = ORC_TYPE_CALL
 };
 
 #ifdef CONFIG_CALL_THUNKS
@@ -153,12 +153,11 @@ static struct orc_entry *orc_callthunk_find(unsigned long ip)
 
 /* Fake frame pointer entry -- used as a fallback for generated code */
 static struct orc_entry orc_fp_entry = {
-	.type		= UNWIND_HINT_TYPE_CALL,
+	.type		= ORC_TYPE_CALL,
 	.sp_reg		= ORC_REG_BP,
 	.sp_offset	= 16,
 	.bp_reg		= ORC_REG_PREV_SP,
 	.bp_offset	= -16,
-	.end		= 0,
 };
 
 static struct orc_entry *orc_find(unsigned long ip)
@@ -250,13 +249,13 @@ static int orc_sort_cmp(const void *_a, const void *_b)
 		return -1;
 
 	/*
-	 * The "weak" section terminator entries need to always be on the left
+	 * The "weak" section terminator entries need to always be first
 	 * to ensure the lookup code skips them in favor of real entries.
 	 * These terminator entries exist to handle any gaps created by
 	 * whitelisted .o files which didn't get objtool generation.
 	 */
 	orc_a = cur_orc_table + (a - cur_orc_ip_table);
-	return orc_a->sp_reg == ORC_REG_UNDEFINED && !orc_a->end ? -1 : 1;
+	return orc_a->type == ORC_TYPE_UNDEFINED ? -1 : 1;
 }
 
 void unwind_module_init(struct module *mod, void *_orc_ip, size_t orc_ip_size,
@@ -474,14 +473,12 @@ bool unwind_next_frame(struct unwind_state *state)
 		 */
 		orc = &orc_fp_entry;
 		state->error = true;
-	}
-
-	/* End-of-stack check for kernel threads: */
-	if (orc->sp_reg == ORC_REG_UNDEFINED) {
-		if (!orc->end)
+	} else {
+		if (orc->type == ORC_TYPE_UNDEFINED)
 			goto err;
 
-		goto the_end;
+		if (orc->type == ORC_TYPE_END_OF_STACK)
+			goto the_end;
 	}
 
 	state->signal = orc->signal;
@@ -554,7 +551,7 @@ bool unwind_next_frame(struct unwind_state *state)
 
 	/* Find IP, SP and possibly regs: */
 	switch (orc->type) {
-	case UNWIND_HINT_TYPE_CALL:
+	case ORC_TYPE_CALL:
 		ip_p = sp - sizeof(long);
 
 		if (!deref_stack_reg(state, ip_p, &state->ip))
@@ -567,7 +564,7 @@ bool unwind_next_frame(struct unwind_state *state)
 		state->prev_regs = NULL;
 		break;
 
-	case UNWIND_HINT_TYPE_REGS:
+	case ORC_TYPE_REGS:
 		if (!deref_stack_regs(state, sp, &state->ip, &state->sp)) {
 			orc_warn_current("can't access registers at %pB\n",
 					 (void *)orig_ip);
@@ -590,13 +587,13 @@ bool unwind_next_frame(struct unwind_state *state)
 		state->full_regs = true;
 		break;
 
-	case UNWIND_HINT_TYPE_REGS_PARTIAL:
+	case ORC_TYPE_REGS_PARTIAL:
 		if (!deref_stack_iret_regs(state, sp, &state->ip, &state->sp)) {
 			orc_warn_current("can't access iret registers at %pB\n",
 					 (void *)orig_ip);
 			goto err;
 		}
-		/* See UNWIND_HINT_TYPE_REGS case comment. */
+		/* See ORC_TYPE_REGS case comment. */
 		state->ip = unwind_recover_rethook(state, state->ip,
 				(unsigned long *)(state->sp - sizeof(long)));
 
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index 5f61c65322be..27ef53fab6bd 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -33,7 +33,7 @@
 
 	.align RETPOLINE_THUNK_SIZE
 SYM_INNER_LABEL(__x86_indirect_thunk_\reg, SYM_L_GLOBAL)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ANNOTATE_NOENDBR
 
 	ALTERNATIVE_2 __stringify(RETPOLINE \reg), \
@@ -75,7 +75,7 @@ SYM_CODE_END(__x86_indirect_thunk_array)
 	.align RETPOLINE_THUNK_SIZE
 
 SYM_INNER_LABEL(__x86_indirect_call_thunk_\reg, SYM_L_GLOBAL)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ANNOTATE_NOENDBR
 
 	CALL_DEPTH_ACCOUNT
@@ -103,7 +103,7 @@ SYM_CODE_END(__x86_indirect_call_thunk_array)
 	.align RETPOLINE_THUNK_SIZE
 
 SYM_INNER_LABEL(__x86_indirect_jump_thunk_\reg, SYM_L_GLOBAL)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ANNOTATE_NOENDBR
 	POLINE \reg
 	ANNOTATE_UNRET_SAFE
diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S
index 7fe564eaf228..c4365a05ab83 100644
--- a/arch/x86/platform/pvh/head.S
+++ b/arch/x86/platform/pvh/head.S
@@ -50,7 +50,7 @@
 #define PVH_DS_SEL		(PVH_GDT_ENTRY_DS * 8)
 
 SYM_CODE_START_LOCAL(pvh_start_xen)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	cld
 
 	lgdt (_pa(gdt))
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index 236447ee9beb..7a4d5e911415 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -288,7 +288,7 @@ EXPORT_SYMBOL(restore_processor_state);
 #endif
 
 #if defined(CONFIG_HIBERNATION) && defined(CONFIG_HOTPLUG_CPU)
-static void resume_play_dead(void)
+static void __noreturn resume_play_dead(void)
 {
 	play_dead_common();
 	tboot_shutdown(TB_SHUTDOWN_WFS);
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
index 4a184f6e4e4d..08f1ceb9eb81 100644
--- a/arch/x86/xen/xen-asm.S
+++ b/arch/x86/xen/xen-asm.S
@@ -165,7 +165,7 @@ xen_pv_trap asm_exc_xen_hypervisor_callback
 SYM_CODE_START(xen_early_idt_handler_array)
 	i = 0
 	.rept NUM_EXCEPTION_VECTORS
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ENDBR
 	pop %rcx
 	pop %r11
@@ -193,7 +193,7 @@ hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32
  * rsp->rax		}
  */
 SYM_CODE_START(xen_iret)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_UNDEFINED
 	ANNOTATE_NOENDBR
 	pushq $0
 	jmp hypercall_iret
diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S
index 91f7a53519a7..643d02900fbb 100644
--- a/arch/x86/xen/xen-head.S
+++ b/arch/x86/xen/xen-head.S
@@ -45,7 +45,7 @@ SYM_CODE_END(hypercall_page)
 #ifdef CONFIG_XEN_PV
 	__INIT
 SYM_CODE_START(startup_xen)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ANNOTATE_NOENDBR
 	cld
 
@@ -71,7 +71,7 @@ SYM_CODE_END(startup_xen)
 #ifdef CONFIG_XEN_PV_SMP
 .pushsection .text
 SYM_CODE_START(asm_cpu_bringup_and_idle)
-	UNWIND_HINT_EMPTY
+	UNWIND_HINT_END_OF_STACK
 	ENDBR
 
 	call cpu_bringup_and_idle