Subject: [PATCH v2 43/52] powerpc/64s/exception: machine check early only runs in HV mode

From: Nicholas Piggin <[email-masked]>
Date: Thu, 20 Jun 2019 15:14:50 +1000

machine_check_common_early and machine_check_handle_early only run in
HVMODE. Remove dead code.

Signed-off-by: Nicholas Piggin <[email-masked]>
---
 arch/powerpc/kernel/exceptions-64s.S | 38 +++++-----------------------
 1 file changed, 6 insertions(+), 32 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index b12755a4f884..f3362adc99e6 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1014,10 +1014,7 @@ TRAMP_REAL_BEGIN(machine_check_common_early)
 	/* Save r9 through r13 from EXMC save area to stack frame. */
 	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
 	mfmsr	r11			/* get MSR value */
-BEGIN_FTR_SECTION
-	ori	r11,r11,MSR_ME		/* turn on ME bit */
-END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
-	ori	r11,r11,MSR_RI		/* turn on RI bit */
+	ori	r11,r11,MSR_ME|MSR_RI	/* turn on ME, RI */
 	LOAD_HANDLER(r12, machine_check_handle_early)
 1:	mtspr	SPRN_SRR0,r12
 	mtspr	SPRN_SRR1,r11
@@ -1124,11 +1121,8 @@ EXC_COMMON_BEGIN(machine_check_handle_early)
 	bl	machine_check_early
 	std	r3,RESULT(r1)	/* Save result */
 	ld	r12,_MSR(r1)
-BEGIN_FTR_SECTION
-	b	4f
-END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
 
-#ifdef	CONFIG_PPC_P7_NAP
+#ifdef CONFIG_PPC_P7_NAP
 	/*
 	 * Check if thread was in power saving mode. We come here when any
 	 * of the following is true:
@@ -1141,7 +1135,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_HVMODE)
 BEGIN_FTR_SECTION
 	rlwinm.	r11,r12,47-31,30,31
 	bne	machine_check_idle_common
-END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
 #endif
 
 	/*
@@ -1150,12 +1144,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
 	 */
 	rldicl.	r11,r12,4,63		/* See if MC hit while in HV mode. */
 	beq	5f
-4:	andi.	r11,r12,MSR_PR		/* See if coming from user. */
+	andi.	r11,r12,MSR_PR		/* See if coming from user. */
 	bne	9f			/* continue in V mode if we are. */
 
 5:
 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
-BEGIN_FTR_SECTION
 	/*
 	 * We are coming from kernel context. Check if we are coming from
 	 * guest. if yes, then we can continue. We will fall through
@@ -1164,7 +1157,6 @@ BEGIN_FTR_SECTION
 	lbz	r11,HSTATE_IN_GUEST(r13)
 	cmpwi	r11,0			/* Check if coming from guest */
 	bne	9f			/* continue if we are. */
-END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 #endif
 	/*
 	 * At this point we are not sure about what context we come from.
@@ -1199,7 +1191,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 	cmpdi	r3,0		/* see if we handled MCE successfully */
 
 	beq	1b		/* if !handled then panic */
-BEGIN_FTR_SECTION
+
 	/*
 	 * Return from MC interrupt.
 	 * Queue up the MCE event so that we can log it later, while
@@ -1208,18 +1200,7 @@ BEGIN_FTR_SECTION
 	bl	machine_check_queue_event
 	MACHINE_CHECK_HANDLER_WINDUP
 	RFI_TO_USER_OR_KERNEL
-FTR_SECTION_ELSE
-	/*
-	 * pSeries: Return from MC interrupt. Before that stay on emergency
-	 * stack and call machine_check_exception to log the MCE event.
-	 */
-	LOAD_HANDLER(r10,mce_return)
-	mtspr	SPRN_SRR0,r10
-	ld	r10,PACAKMSR(r13)
-	mtspr	SPRN_SRR1,r10
-	RFI_TO_KERNEL
-	b	.
-ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
+
 9:
 	/* Deliver the machine check to host kernel in V mode. */
 	MACHINE_CHECK_HANDLER_WINDUP
@@ -1238,13 +1219,6 @@ EXC_COMMON_BEGIN(unrecover_mce)
 	bl	unrecoverable_exception
 	b	1b
 
-EXC_COMMON_BEGIN(mce_return)
-	/* Invoke machine_check_exception to print MCE event and return. */
-	addi	r3,r1,STACK_FRAME_OVERHEAD
-	bl	machine_check_exception
-	MACHINE_CHECK_HANDLER_WINDUP
-	RFI_TO_KERNEL
-	b	.
 
 EXC_REAL_BEGIN(data_access, 0x300, 0x80)
 	EXCEPTION_PROLOG_0 PACA_EXGEN
-- 
2.20.1