From patchwork Fri Jan 4 17:44:15 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 1934121 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork2.kernel.org (Postfix) with ESMTP id E7442DFABD for ; Fri, 4 Jan 2013 17:48:09 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TrBKY-0005DG-L1; Fri, 04 Jan 2013 17:45:18 +0000 Received: from service87.mimecast.com ([91.220.42.44]) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TrBKL-0005BY-Mq for linux-arm-kernel@lists.infradead.org; Fri, 04 Jan 2013 17:45:07 +0000 Received: from cam-owa2.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.21]) by service87.mimecast.com; Fri, 04 Jan 2013 17:45:01 +0000 Received: from e102391-lin.cambridge.arm.com ([10.1.255.212]) by cam-owa2.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Fri, 4 Jan 2013 17:44:58 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: [PATCH 2/2] ARM: hyp: simplify __hyp_stub_install epilog Date: Fri, 4 Jan 2013 17:44:15 +0000 Message-Id: <1357321455-9264-3-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 1.8.1 In-Reply-To: <1357321455-9264-1-git-send-email-marc.zyngier@arm.com> References: <1357321455-9264-1-git-send-email-marc.zyngier@arm.com> X-OriginalArrivalTime: 04 Jan 2013 17:44:58.0954 (UTC) FILETIME=[3727DAA0:01CDEAA3] X-MC-Unique: 113010417450100401 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130104_124506_050153_C92068F9 X-CRM114-Status: GOOD ( 12.56 ) X-Spam-Score: -2.6 (--) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-2.6 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [91.220.42.44 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Dave Martin , Harry Liebel X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org __hyp_stub_install duplicates quite a bit of safe_svcmode_maskall by forcing the CPU back to SVC. This is unnecessary, as safe_svcmode_maskall is called just after. Furthermore, the way we build SPSR_hyp is buggy as we fail to mask the interrupts, leading to interesting behaviours on TC2 + UEFI. The fix is to simply remove this code and rely on safe_svcmode_maskall to do the right thing. Cc: Dave Martin Reported-by: Harry Liebel Signed-off-by: Marc Zyngier Reviewed-by: Dave Martin --- arch/arm/kernel/hyp-stub.S | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/arch/arm/kernel/hyp-stub.S b/arch/arm/kernel/hyp-stub.S index 65b2417..da7e19f 100644 --- a/arch/arm/kernel/hyp-stub.S +++ b/arch/arm/kernel/hyp-stub.S @@ -120,7 +120,8 @@ ENTRY(__hyp_stub_install_secondary) * Eventually, CPU-specific code might be needed -- assume not for now * * This code relies on the "eret" instruction to synchronize the - * various coprocessor accesses. + * various coprocessor accesses. This is done when we switch to SVC + * (see safe_svcmode_maskall). */ @ Now install the hypervisor stub: adr r7, __hyp_stub_vectors @@ -155,14 +156,7 @@ THUMB( orr r7, #(1 << 30) ) @ HSCTLR.TE 1: #endif - bic r7, r4, #MODE_MASK - orr r7, r7, #SVC_MODE -THUMB( orr r7, r7, #PSR_T_BIT ) - msr spsr_cxsf, r7 @ This is SPSR_hyp. - - __MSR_ELR_HYP(14) @ msr elr_hyp, lr - __ERET @ return, switching to SVC mode - @ The boot CPU mode is left in r4. + bx lr @ The boot CPU mode is left in r4. ENDPROC(__hyp_stub_install_secondary) __hyp_stub_do_trap: