From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailapp01.imgtec.com ([195.59.15.196]:17611 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27010905AbbAPKxbuLxmJ (ORCPT ); Fri, 16 Jan 2015 11:53:31 +0100 Received: from KLMAIL01.kl.imgtec.org (unknown [192.168.5.35]) by Websense Email Security Gateway with ESMTPS id 1F174F6945A6A for ; Fri, 16 Jan 2015 10:53:24 +0000 (GMT) From: Markos Chandras Subject: [PATCH RFC v2 45/70] MIPS: kernel: branch: Prevent BLTZL emulation for MIPS R6 Date: Fri, 16 Jan 2015 10:49:24 +0000 Message-ID: <1421405389-15512-46-git-send-email-markos.chandras@imgtec.com> In-Reply-To: <1421405389-15512-1-git-send-email-markos.chandras@imgtec.com> References: <1421405389-15512-1-git-send-email-markos.chandras@imgtec.com> MIME-Version: 1.0 Content-Type: text/plain Return-Path: Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-subscribe: List-owner: List-post: List-archive: To: linux-mips@linux-mips.org Cc: Markos Chandras Message-ID: <20150116104924.arrRVMGL98pWbglPGz1yVlbHb-soT5bcwxgKMx6WIzw@z> MIPS R6 removed the BLTZL instruction so do not try to emulate it if the R2-to-R6 emulator is not present. Signed-off-by: Markos Chandras --- arch/mips/kernel/branch.c | 5 +++++ arch/mips/math-emu/cp1emu.c | 2 ++ 2 files changed, 7 insertions(+) diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c index 9b622ca391d8..502bf2aeb834 100644 --- a/arch/mips/kernel/branch.c +++ b/arch/mips/kernel/branch.c @@ -436,6 +436,11 @@ int __compute_return_epc_for_insn(struct pt_regs *regs, switch (insn.i_format.rt) { case bltz_op: case bltzl_op: + if (NO_R6EMU && (insn.i_format.rt == bltzl_op)) { + ret = -SIGILL; + /* not emulating the branch likely for R6 */ + break; + } if ((long)regs->regs[insn.i_format.rs] < 0) { epc = epc + 4 + (insn.i_format.simmediate << 2); if (insn.i_format.rt == bltzl_op) diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index 9707af43913f..e70513d552f6 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -465,6 +465,8 @@ static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, /* Fall through */ case bltz_op: case bltzl_op: + if (NO_R6EMU && (insn.i_format.rt == bltzl_op)) + break; if ((long)regs->regs[insn.i_format.rs] < 0) *contpc = regs->cp0_epc + dec_insn.pc_inc + -- 2.2.1