[patch 26/26] POWERPC: Fix handling of stfiwx math emulation

Greg KH
2007-10-31T15:31:41Z

[-- Attachment #1: powerpc-fix-handling-of-stfiwx-math-emulation.patch --]
[-- Type: text/plain, Size: 1258 bytes --]

2.6.22-stable review patch. If anyone has any objections, please let us
know.

------------------
From: Kumar Gala <galak@kernel.crashing.org>

patch ba02946a903015840ef672ccc9dc8620a7e83de6 in mainline

Its legal for the stfiwx instruction to have RA = 0 as part of its
effective address calculation. This is illegal for all other XE
form instructions.

Add code to compute the proper effective address for stfiwx if
RA = 0 rather than treating it as illegal.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
arch/powerpc/math-emu/math.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

--- a/arch/powerpc/math-emu/math.c
+++ b/arch/powerpc/math-emu/math.c
@@ -407,11 +407,16 @@ do_mathemu(struct pt_regs *regs)

case XE:
idx = (insn >> 16) & 0x1f;
- if (!idx)
- goto illegal;
-
op0 = (void *)&current->thread.fpr[(insn >> 21) & 0x1f];
- op1 = (void *)(regs->gpr[idx] + regs->gpr[(insn >> 11) & 0x1f]);
+ if (!idx) {
+ if (((insn >> 1) & 0x3ff) == STFIWX)
+ op1 = (void *)(regs->gpr[(insn >> 11) & 0x1f]);
+ else
+ goto illegal;
+ } else {
+ op1 = (void *)(regs->gpr[idx] + regs->gpr[(insn >> 11) & 0x1f]);
+ }
+
break;

case XEU:

--