Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752702AbbKWL7M (ORCPT ); Mon, 23 Nov 2015 06:59:12 -0500 Received: from mail.dev.rtsoft.ru ([213.79.90.226]:37725 "EHLO dev.rtsoft.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751076AbbKWL7K (ORCPT ); Mon, 23 Nov 2015 06:59:10 -0500 From: nyushchenko@dev.rtsoft.ru To: Russell King , Will Deacon , Ard Biesheuvel , Rob Herring , Ian Campbell , Pavel Machek , Mason , Paul Kocialkowski , Masahiro Yamada Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, nyushchenko@dev.rtsoft.ru, kuznetsovg@dev.rtsoft.ru Subject: [RFC/PATCH] arm: do not skip SMP init calls on SMP_ON_UP case Date: Mon, 23 Nov 2015 14:59:06 +0300 Message-Id: <1448279946-19975-1-git-send-email-nyushchenko@dev.rtsoft.ru> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2129 Lines: 65 From: Nikita Yushchenko While running an imx6s boasrd, I got following message in boot log: [ 0.032414] CPU1: failed to boot: -38 This looked strange: imx6s is singe-core and kernel perfectly knows that. However, for some reason it tries to initialize CPU 1? I found this to be caused by - CONFIG_SMP_ON_UP successfully detects that system is single core, - this causes is_smp() to return false, - this causes setup_arch() to skip smp_init_cpus() call, - this skips board-specific code that sets cpu_possible mask. By looking at the code, I don't understand why several initialization routines are called only in is_smp() case - while other kernel CONFIG_SMP code does not check is_smp() every time and uses what should have been initialized by skipped routines. Thus I propose making these init calls regardless of is_smp() check. Calls are already conditional on CONFIG_SMP. This will make init and usage sides consistent. Signed-off-by: Nikita Yushchenko --- arch/arm/kernel/setup.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 20edd34..8a14fce 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -980,16 +980,14 @@ void __init setup_arch(char **cmdline_p) psci_dt_init(); xen_early_init(); #ifdef CONFIG_SMP - if (is_smp()) { - if (!mdesc->smp_init || !mdesc->smp_init()) { - if (psci_smp_available()) - smp_set_ops(&psci_smp_ops); - else if (mdesc->smp) - smp_set_ops(mdesc->smp); - } - smp_init_cpus(); - smp_build_mpidr_hash(); + if (!mdesc->smp_init || !mdesc->smp_init()) { + if (psci_smp_available()) + smp_set_ops(&psci_smp_ops); + else if (mdesc->smp) + smp_set_ops(mdesc->smp); } + smp_init_cpus(); + smp_build_mpidr_hash(); #endif if (!is_smp()) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/