Re: [PATCH v4 20/24] openrisc: entry: Fix delay slot detection

From: Jonas Bonn
Date: Fri Feb 24 2017 - 04:52:45 EST


On 02/24/2017 05:32 AM, Stafford Horne wrote:
Use execption SR stored in pt_regs for detection, the current SR is not
correct as the handler is running after return from exception.

Also, The code that checks for a delay slot uses a flag bitmask and then
wants to check if the result is not zero. The test it implemented was
wrong.

Correct it by changing the test to check result against non zero.

This wants to be two patches as you are changing two different things.

/Joans


Signed-off-by: Stafford Horne <shorne@xxxxxxxxx>
---
arch/openrisc/kernel/entry.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index daae2a4..bc65008 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -258,9 +258,9 @@ EXCEPTION_ENTRY(_data_page_fault_handler)
#else
- l.mfspr r6,r0,SPR_SR // SR
+ l.lwz r6,PT_SR(r3) // SR
l.andi r6,r6,SPR_SR_DSX // check for delay slot exception
- l.sfeqi r6,0x1 // exception happened in delay slot
+ l.sfne r6,r0 // exception happened in delay slot
l.bnf 7f
l.lwz r6,PT_PC(r3) // address of an offending insn