From 1d2a90a03ae8f6c23d96c54f4ac1e371ac9b474a Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Thu, 15 Jun 2017 09:46:39 +1000 Subject: [PATCH] powerpc: Fix emulation of mfocrf in emulate_step() From POWER4 onwards, mfocrf() only places the specified CR field into the destination GPR, and the rest of it is set to 0. The PowerPC AS from version 3.0 now requires this behaviour. The emulation code currently puts the entire CR into the destination GPR. Fix it. Fixes: a600af571b8b ("[POWERPC] Emulate more instructions in software") Cc: stable@vger.kernel.org # v2.6.22+ Signed-off-by: Anton Blanchard Acked-by: Naveen N. Rao Signed-off-by: Michael Ellerman --- arch/powerpc/lib/sstep.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index fb84f51b1f0b7..ee33327686aec 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -966,6 +966,19 @@ int analyse_instr(struct instruction_op *op, struct pt_regs *regs, #endif case 19: /* mfcr */ + if ((instr >> 20) & 1) { + imm = 0xf0000000UL; + for (sh = 0; sh < 8; ++sh) { + if (instr & (0x80000 >> sh)) { + regs->gpr[rd] = regs->ccr & imm; + break; + } + imm >>= 4; + } + + goto instr_done; + } + regs->gpr[rd] = regs->ccr; regs->gpr[rd] &= 0xffffffffUL; goto instr_done; -- 2.39.5