From patchwork Wed Mar 9 16:35:44 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Will Deacon X-Patchwork-Id: 63720 Delivered-To: patch@linaro.org Received: by 10.112.199.169 with SMTP id jl9csp2746162lbc; Wed, 9 Mar 2016 08:35:48 -0800 (PST) X-Received: by 10.66.102.104 with SMTP id fn8mr52026178pab.129.1457541348183; Wed, 09 Mar 2016 08:35:48 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 86si13507089pfr.63.2016.03.09.08.35.47; Wed, 09 Mar 2016 08:35:48 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933266AbcCIQfq (ORCPT + 30 others); Wed, 9 Mar 2016 11:35:46 -0500 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:58705 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753712AbcCIQfk (ORCPT ); Wed, 9 Mar 2016 11:35:40 -0500 Received: from edgewater-inn.cambridge.arm.com (edgewater-inn.cambridge.arm.com [10.1.203.121]) by cam-admin0.cambridge.arm.com (8.12.6/8.12.6) with ESMTP id u29GZQWr002358; Wed, 9 Mar 2016 16:35:26 GMT Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id 192D91AE111E; Wed, 9 Mar 2016 16:35:45 +0000 (GMT) From: Will Deacon To: linux-kernel@vger.kernel.org Cc: Will Deacon , Tony Luck , Heiko Carstens , Andrew Morton Subject: [PATCH] Kconfig: disable LATENCYTOP for IA64 Date: Wed, 9 Mar 2016 16:35:44 +0000 Message-Id: <1457541344-16961-1-git-send-email-will.deacon@arm.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit da48d094ce5d ("Kconfig: remove HAVE_LATENCYTOP_SUPPORT") allows CONFIG_LATENCYTOP to be selected on all architectures, since save_stack_trace_tsk is now provided unconditionally by core code. Unfortunately, this results in a build error for ia64 when the option is enabled: arch/ia64/kernel/entry.S: Assembler messages: arch/ia64/kernel/entry.S:621: Error: Operand 2 of `adds' should be a 14-bit integer (-8192-8191) arch/ia64/kernel/entry.S:728: Error: Operand 2 of `adds' should be a 14-bit integer (-8192-8191) arch/ia64/kernel/entry.S:859: Error: Operand 2 of `adds' should be a 14-bit integer (-8192-8191) make[1]: *** [arch/ia64/kernel/entry.o] Error 1 This is because task_struct is now over 8k thanks to the latency_record array, which means that the 14-bit immediate offset expect by the adds instruction to grab hold of the thread info flags is now out-of-range on ia64. Fixing the ia64 entry code without making it less efficient is beyond me, but rather than revert da48d094ce5d entirely, we can simply make LATENCYTOP depend on !IA64 until somebody brave steps up to tackle the entry code over there. Cc: Tony Luck Cc: Heiko Carstens Cc: Andrew Morton Reported-by: Al Viro Signed-off-by: Will Deacon --- I previously reported this on linux-arch, but the conversation didn't go anywhere: http://marc.info/?l=linux-arch&m=145390684108109 lib/Kconfig.debug | 1 + 1 file changed, 1 insertion(+) -- 2.1.4 diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 8bfd1aca7a3d..c8d12808b9aa 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1615,6 +1615,7 @@ config LATENCYTOP depends on DEBUG_KERNEL depends on STACKTRACE_SUPPORT depends on PROC_FS + depends on !IA64 select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC select KALLSYMS select KALLSYMS_ALL