[PATCH v3 13/14] powerpc/hw_breakpoints: Initial support for prefixed instructions

[Jordan Niethe]

Currently when getting an instruction to emulate in
hw_breakpoint_handler() we do not load the suffix of a prefixed
instruction. Ensure we load the suffix if the instruction we need to
emulate is a prefixed instruction.

Signed-off-by: Jordan Niethe <jniethe5 at gmail.com>
---
v2: Rename sufx to suffix
v3: Add __user to type cast to remove sparse warning
---
 arch/powerpc/kernel/hw_breakpoint.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
index 3a7ec6760dab..edf46356dfb2 100644
--- a/arch/powerpc/kernel/hw_breakpoint.c
+++ b/arch/powerpc/kernel/hw_breakpoint.c
@@ -243,15 +243,16 @@ dar_range_overlaps(unsigned long dar, int size, struct arch_hw_breakpoint *info)
 static bool stepping_handler(struct pt_regs *regs, struct perf_event *bp,
 			     struct arch_hw_breakpoint *info)
 {
-	unsigned int instr = 0;
+	unsigned int instr = 0, suffix = 0;
 	int ret, type, size;
 	struct instruction_op op;
 	unsigned long addr = info->address;
 
-	if (__get_user_inatomic(instr, (unsigned int *)regs->nip))
+	if (__get_user_instr_inatomic(instr, suffix,
+				      (unsigned int __user *)regs->nip))
 		goto fail;
 
-	ret = analyse_instr(&op, regs, instr, PPC_NO_SUFFIX);
+	ret = analyse_instr(&op, regs, instr, suffix);
 	type = GETTYPE(op.type);
 	size = GETSIZE(op.type);
 
@@ -275,7 +276,7 @@ static bool stepping_handler(struct pt_regs *regs, struct perf_event *bp,
 		return false;
 	}
 
-	if (!emulate_step(regs, instr, PPC_NO_SUFFIX))
+	if (!emulate_step(regs, instr, suffix))
 		goto fail;
 
 	return true;
-- 
2.17.1