From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 16 Jan 2015 12:03:56 +0100 (CET) Received: from mailapp01.imgtec.com ([195.59.15.196]:37123 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27010877AbbAPKxa30sSp (ORCPT ); Fri, 16 Jan 2015 11:53:30 +0100 Received: from KLMAIL01.kl.imgtec.org (unknown [192.168.5.35]) by Websense Email Security Gateway with ESMTPS id CAF4D94A938B6 for ; Fri, 16 Jan 2015 10:53:27 +0000 (GMT) Received: from LEMAIL01.le.imgtec.org (192.168.152.62) by KLMAIL01.kl.imgtec.org (192.168.5.35) with Microsoft SMTP Server (TLS) id 14.3.195.1; Fri, 16 Jan 2015 10:53:29 +0000 Received: from mchandras-linux.le.imgtec.org (192.168.154.96) by LEMAIL01.le.imgtec.org (192.168.152.62) with Microsoft SMTP Server (TLS) id 14.3.210.2; Fri, 16 Jan 2015 10:53:29 +0000 From: Markos Chandras To: CC: Markos Chandras Subject: [PATCH RFC v2 48/70] MIPS: kernel: branch: Prevent BGEZAL emulation for MIPS R6 Date: Fri, 16 Jan 2015 10:49:27 +0000 Message-ID: <1421405389-15512-49-git-send-email-markos.chandras@imgtec.com> X-Mailer: git-send-email 2.2.1 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 X-Originating-IP: [192.168.154.96] Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 45188 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: markos.chandras@imgtec.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips MIPS R6 removed the BGEZAL 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 | 22 ++++++++++++++++++++++ arch/mips/math-emu/cp1emu.c | 4 ++++ 2 files changed, 26 insertions(+) diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c index 311a2223da59..2273307f7c51 100644 --- a/arch/mips/kernel/branch.c +++ b/arch/mips/kernel/branch.c @@ -502,7 +502,29 @@ int __compute_return_epc_for_insn(struct pt_regs *regs, case bgezal_op: case bgezall_op: + if (NO_R6EMU && (insn.i_format.rs || + insn.i_format.rt == bgezall_op)) { + ret = -SIGILL; + break; + } regs->regs[31] = epc + 8; + /* + * OK we are here either because we hit a BAL + * instruction or because we are emulating an + * old bgezal{,l} one. Lets figure out what the + * case really is. + */ + if (!insn.i_format.rs) { + /* + * BAL or BGEZAL with rs == 0 + * Doesn't matter if we are R6 or not. The + * result is the same + */ + regs->cp0_epc += 4 + + (insn.i_format.simmediate << 2); + break; + } + /* Now do the real thing for non-R6 BGEZAL{,L} */ if ((long)regs->regs[insn.i_format.rs] >= 0) { epc = epc + 4 + (insn.i_format.simmediate << 2); if (insn.i_format.rt == bgezall_op) diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index 5429efe24d5a..8aa6a451104b 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -482,6 +482,10 @@ static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, return 1; case bgezal_op: case bgezall_op: + if (NO_R6EMU && (insn.i_format.rs || + insn.i_format.rt == bgezall_op)) + break; + regs->regs[31] = regs->cp0_epc + dec_insn.pc_inc + dec_insn.next_pc_inc; -- 2.2.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailapp01.imgtec.com ([195.59.15.196]:37123 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S27010877AbbAPKxa30sSp (ORCPT ); Fri, 16 Jan 2015 11:53:30 +0100 Received: from KLMAIL01.kl.imgtec.org (unknown [192.168.5.35]) by Websense Email Security Gateway with ESMTPS id CAF4D94A938B6 for ; Fri, 16 Jan 2015 10:53:27 +0000 (GMT) From: Markos Chandras Subject: [PATCH RFC v2 48/70] MIPS: kernel: branch: Prevent BGEZAL emulation for MIPS R6 Date: Fri, 16 Jan 2015 10:49:27 +0000 Message-ID: <1421405389-15512-49-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: <20150116104927.4_zjdamDNc86fQxSGdvb2CSyWKn9PTP_aW8qNbHE6hg@z> MIPS R6 removed the BGEZAL 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 | 22 ++++++++++++++++++++++ arch/mips/math-emu/cp1emu.c | 4 ++++ 2 files changed, 26 insertions(+) diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c index 311a2223da59..2273307f7c51 100644 --- a/arch/mips/kernel/branch.c +++ b/arch/mips/kernel/branch.c @@ -502,7 +502,29 @@ int __compute_return_epc_for_insn(struct pt_regs *regs, case bgezal_op: case bgezall_op: + if (NO_R6EMU && (insn.i_format.rs || + insn.i_format.rt == bgezall_op)) { + ret = -SIGILL; + break; + } regs->regs[31] = epc + 8; + /* + * OK we are here either because we hit a BAL + * instruction or because we are emulating an + * old bgezal{,l} one. Lets figure out what the + * case really is. + */ + if (!insn.i_format.rs) { + /* + * BAL or BGEZAL with rs == 0 + * Doesn't matter if we are R6 or not. The + * result is the same + */ + regs->cp0_epc += 4 + + (insn.i_format.simmediate << 2); + break; + } + /* Now do the real thing for non-R6 BGEZAL{,L} */ if ((long)regs->regs[insn.i_format.rs] >= 0) { epc = epc + 4 + (insn.i_format.simmediate << 2); if (insn.i_format.rt == bgezall_op) diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index 5429efe24d5a..8aa6a451104b 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -482,6 +482,10 @@ static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, return 1; case bgezal_op: case bgezall_op: + if (NO_R6EMU && (insn.i_format.rs || + insn.i_format.rt == bgezall_op)) + break; + regs->regs[31] = regs->cp0_epc + dec_insn.pc_inc + dec_insn.next_pc_inc; -- 2.2.1