Subject: [PATCH v6 09/39] powerpc/64s: move bad_page_fault handling to C

From: Nicholas Piggin <[email-masked]>
Date: Sat, 16 Jan 2021 02:49:42 +1000

This simplifies code, and it is also useful when introducing
interrupt handler wrappers when introducing wrapper functionality
that doesn't cope with asm entry code calling into more than one
handler function.

32-bit and 64e still have some such cases, which limits some ways
they can use interrupt wrappers.

Signed-off-by: Nicholas Piggin <[email-masked]>
---
 arch/powerpc/kernel/exceptions-64s.S | 12 ------------
 arch/powerpc/mm/fault.c              |  4 ++++
 2 files changed, 4 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index b90d3cde14cf..e69a912c2cc6 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1447,12 +1447,6 @@ BEGIN_MMU_FTR_SECTION
 MMU_FTR_SECTION_ELSE
 	bl	do_page_fault
 ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
-	cmpdi	r3,0
-	beq+	interrupt_return
-	mr	r5,r3
-	addi	r3,r1,STACK_FRAME_OVERHEAD
-	ld	r4,_DAR(r1)
-	bl	__bad_page_fault
 	b	interrupt_return
 
 1:	bl	do_break
@@ -1557,12 +1551,6 @@ BEGIN_MMU_FTR_SECTION
 MMU_FTR_SECTION_ELSE
 	bl	do_page_fault
 ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
-	cmpdi	r3,0
-	beq+	interrupt_return
-	mr	r5,r3
-	addi	r3,r1,STACK_FRAME_OVERHEAD
-	ld	r4,_DAR(r1)
-	bl	__bad_page_fault
 	b	interrupt_return
 
 	GEN_KVM instruction_access
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index e4121fd9fcf1..965c89e63997 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -556,6 +556,10 @@ long do_page_fault(struct pt_regs *regs)
 		if (likely(entry)) {
 			instruction_pointer_set(regs, extable_fixup(entry));
 			err = 0;
+		} else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64)) {
+			/* 32 and 64e handle this in asm */
+			__bad_page_fault(regs, err);
+			err = 0;
 		}
 	}
 
-- 
2.23.0