From patchwork Tue May 14 17:00:12 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 2568111 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) by patchwork1.kernel.org (Postfix) with ESMTP id B57573FD85 for ; Tue, 14 May 2013 17:04:40 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UcIbR-0004EB-C9; Tue, 14 May 2013 17:01:32 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UcIak-0004dA-0A; Tue, 14 May 2013 17:00:46 +0000 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UcIah-0004cK-A7 for linux-arm-kernel@lists.infradead.org; Tue, 14 May 2013 17:00:44 +0000 Received: from mudshark.cambridge.arm.com (mudshark.cambridge.arm.com [10.1.203.36]) by cam-admin0.cambridge.arm.com (8.12.6/8.12.6) with ESMTP id r4EH0Hki028755; Tue, 14 May 2013 18:00:17 +0100 (BST) Received: by mudshark.cambridge.arm.com (Postfix, from userid 1000) id 8F2EEC2B17; Tue, 14 May 2013 18:00:14 +0100 (BST) From: Will Deacon To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] ARM: vfp: ensure VFP_arch is non-zero when VFP is not supported Date: Tue, 14 May 2013 18:00:12 +0100 Message-Id: <1368550812-30492-1-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 1.8.2.2 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130514_130043_587510_70701CDC X-CRM114-Status: GOOD ( 13.38 ) X-Spam-Score: -7.5 (-------) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-7.5 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [217.140.96.50 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.6 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Will Deacon X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Commit d3f79584a8b5 ("ARM: cleanup undefined instruction entry code") improved the register scheduling when handling undefined instructions. A side effect of this is that r5 is now used as a temporary, whilst the VFP probing code relies on r5 containing a non-zero value when VFP is not supported. This patch fixes the VFP detection code so that we don't rely on the contents of r5. Without this patch, Linux dies loudly on CPUs without VFP support. Signed-off-by: Will Deacon --- arch/arm/vfp/entry.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/vfp/entry.S b/arch/arm/vfp/entry.S index 323ce1a..46e1749 100644 --- a/arch/arm/vfp/entry.S +++ b/arch/arm/vfp/entry.S @@ -60,7 +60,7 @@ ENTRY(vfp_testing_entry) str r11, [r10, #TI_PREEMPT] #endif ldr r0, VFP_arch_address - str r5, [r0] @ known non-zero value + str r0, [r0] @ set to non-zero value mov pc, r9 @ we have handled the fault ENDPROC(vfp_testing_entry)