[PATCH 4.9 21/44] powerpc: Emulation support for load/store instructions on LE

Greg Kroah-Hartman
2017-03-16T14:33:22Z

From: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>

commit e148bd17f48bd17fca2f4f089ec879fa6e47e34c upstream.

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 <anton@samba.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/lib/sstep.c | 20 --------------------
1 file changed, 20 deletions(-)

--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -1807,8 +1807,6 @@ int __kprobes emulate_step(struct pt_reg
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_reg
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_reg
goto ldst_done;

case LOAD:
- if (regs->msr & MSR_LE)
- return 0;
err = read_mem(&regs->gpr[op.reg], op.ea, size, regs);
if (!err) {
if (op.type & SIGNEXT)
@@ -1872,8 +1866,6 @@ int __kprobes emulate_step(struct pt_reg

#ifdef CONFIG_PPC_FPU
case LOAD_FP:
- if (regs->msr & MSR_LE)
- return 0;
if (size == 4)
err = do_fp_load(op.reg, do_lfs, op.ea, size, regs);
else
@@ -1882,15 +1874,11 @@ int __kprobes emulate_step(struct pt_reg
#endif
#ifdef CONFIG_ALTIVEC
case LOAD_VMX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vec_load(op.reg, do_lvx, op.ea & ~0xfUL, regs);
goto ldst_done;
#endif
#ifdef CONFIG_VSX
case LOAD_VSX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vsx_load(op.reg, do_lxvd2x, op.ea, regs);
goto ldst_done;
#endif
@@ -1913,8 +1901,6 @@ int __kprobes emulate_step(struct pt_reg
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) &&
@@ -1927,8 +1913,6 @@ int __kprobes emulate_step(struct pt_reg

#ifdef CONFIG_PPC_FPU
case STORE_FP:
- if (regs->msr & MSR_LE)
- return 0;
if (size == 4)
err = do_fp_store(op.reg, do_stfs, op.ea, size, regs);
else
@@ -1937,15 +1921,11 @@ int __kprobes emulate_step(struct pt_reg
#endif
#ifdef CONFIG_ALTIVEC
case STORE_VMX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vec_store(op.reg, do_stvx, op.ea & ~0xfUL, regs);
goto ldst_done;
#endif
#ifdef CONFIG_VSX
case STORE_VSX:
- if (regs->msr & MSR_LE)
- return 0;
err = do_vsx_store(op.reg, do_stxvd2x, op.ea, regs);
goto ldst_done;
#endif