Re: [RFC] ppc64le: Enable emulation support for simple Load/Store instructions

[Greg KH]

On Thu, Oct 20, 2016 at 12:01:55PM +0530, Ravi Bangoria wrote:
> emulate_step() uses a number of underlying kernel functions that were
> initially not enabled for LE. This has been rectified since. So, fix
> emulate_step() for LE for the corresponding instructions.
> 
> Reported-by: Anton Blanchard 
> Signed-off-by: Ravi Bangoria 
> ---
> Note: This patch only enables LOAD, STORE, LARX and STCX instructions.
>   I'll send a subsequent patch for other types like LOAD_FP,
>   LOAD_VMX etc.
> 
>  arch/powerpc/lib/sstep.c | 8 
>  1 file changed, 8 deletions(-)



This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read Documentation/stable_kernel_rules.txt
for how to do this properly.

[RFC] ppc64le: Enable emulation support for simple Load/Store instructions

[Ravi Bangoria]

emulate_step() uses a number of underlying kernel functions that were
initially not enabled for LE. This has been rectified since. So, fix
emulate_step() for LE for the corresponding instructions.

Reported-by: Anton Blanchard 
Signed-off-by: Ravi Bangoria 
---
Note: This patch only enables LOAD, STORE, LARX and STCX instructions.
  I'll send a subsequent patch for other types like LOAD_FP,
  LOAD_VMX etc.

 arch/powerpc/lib/sstep.c | 8 
 1 file changed, 8 deletions(-)

diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 3362299..82323ef 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1807,8 +1807,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned 
int instr)
goto instr_done;
 
case LARX:
-   if (regs->msr & MSR_LE)
-   return 0;
if (op.ea & (size - 1))
break;  /* can't handle misaligned */
err = -EFAULT;
@@ -1832,8 +1830,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned 
int instr)
goto ldst_done;
 
case STCX:
-   if (regs->msr & MSR_LE)
-   return 0;
if (op.ea & (size - 1))
break;  /* can't handle misaligned */
err = -EFAULT;
@@ -1859,8 +1855,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned 
int instr)
goto ldst_done;
 
case LOAD:
-   if (regs->msr & MSR_LE)
-   return 0;
err = read_mem(®s->gpr[op.reg], op.ea, size, regs);
if (!err) {
if (op.type & SIGNEXT)
@@ -1913,8 +1907,6 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned 
int instr)
goto instr_done;
 
case STORE:
-   if (regs->msr & MSR_LE)
-   return 0;
if ((op.type & UPDATE) && size == sizeof(long) &&
op.reg == 1 && op.update_reg == 1 &&
!(regs->msr & MSR_PR) &&
-- 
1.8.3.1