From patchwork Mon Oct 29 18:07:06 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 10659959 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D8D3017DF for ; Mon, 29 Oct 2018 18:08:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C878329C45 for ; Mon, 29 Oct 2018 18:08:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BBEF029C4A; Mon, 29 Oct 2018 18:08:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 643CD29C45 for ; Mon, 29 Oct 2018 18:08:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728457AbeJ3C6b (ORCPT ); Mon, 29 Oct 2018 22:58:31 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:33376 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728366AbeJ3C6S (ORCPT ); Mon, 29 Oct 2018 22:58:18 -0400 Received: by mail-pg1-f196.google.com with SMTP id q5-v6so595737pgv.0 for ; Mon, 29 Oct 2018 11:08:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=5KlK5EoYecHiEwx2KYOj1AK3WWuK24K/BTuRZp/Hgn0=; b=ViKF3X5QZz1G04Kuc+UrpCLOIvvtASddvUpgEhbE2NwCsDxuq6JsW/AfF3MtdzfNcH x4aFvJIFkNdrS8l2CQjvpOEnAdP+LsFKZAoe9CdyAH5M9odaITFSuzPbsiwDohBeU3UQ YDDibS0wr7JOOkRxMW/g3gib7jVbkYmN9FZJo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=5KlK5EoYecHiEwx2KYOj1AK3WWuK24K/BTuRZp/Hgn0=; b=U1iqvdKBw35GpHwM3clNOBHwzhIs6BACq2m9u6WryDR+O1rA3cMfTr1lLZ6EeEgire XzT1KsjjWLAQmaYxuoDNG21OSPP8EM73+hi4lGwDNDKyOWercT/2Qod3T5278zh9DnuQ CY+YqESj5FRWJ2PhC5rquzlJf/npcPOm0mA+RNImKxMeKKxmrwkRx6B0yROjKsGDNLuY PwOnj+CTq2SvUpYfyhuOdqd0N5a/Ll1PRfq3opnOsjd2mqZim8xoAg5MxYfOwAv/fwZZ mB1c71oNnwhtdc+GnWv/c7aMQB7TgerLfU0I8sespAAoCH9sAbZ7Pgs2ILOJgnkM6jPO 2Vog== X-Gm-Message-State: AGRZ1gIHXoNNH0rtIAJ87WCjeJmMMvNWspb+XeLLJ8unO8x07SbQ3PlA jWjv/JtIvfwUsAS+uri+HwhKDg== X-Google-Smtp-Source: AJdET5dnes+lqSdsKf+M8kej513uIWGXuNg0nbxyLNaYWMhztTpOmHr2lEByvMdxDcC5rsUHz1VWbw== X-Received: by 2002:a62:7a92:: with SMTP id v140-v6mr9434788pfc.46.1540836514355; Mon, 29 Oct 2018 11:08:34 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:c8e0:70d7:4be7:a36]) by smtp.gmail.com with ESMTPSA id u13-v6sm20537765pgp.18.2018.10.29.11.08.32 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 29 Oct 2018 11:08:33 -0700 (PDT) From: Douglas Anderson To: Jason Wessel , Daniel Thompson , tglx@linutronix.de, mingo@kernel.org, gregkh@linuxfoundation.org Cc: linux-arm-msm@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, Douglas Anderson , linux-mips@linux-mips.org, linux-sh@vger.kernel.org, peterz@infradead.org, linux-hexagon@vger.kernel.org, frederic@kernel.org, riel@surriel.com, linux-kernel@vger.kernel.org, luto@kernel.org, sparclinux@vger.kernel.org, linux-snps-arc@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 6/7] smp: Don't yell about IRQs disabled in kgdb_roundup_cpus() Date: Mon, 29 Oct 2018 11:07:06 -0700 Message-Id: <20181029180707.207546-7-dianders@chromium.org> X-Mailer: git-send-email 2.19.1.568.g152ad8e336-goog In-Reply-To: <20181029180707.207546-1-dianders@chromium.org> References: <20181029180707.207546-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In kgdb_roundup_cpus() we've got code that looks like: local_irq_enable(); smp_call_function(kgdb_call_nmi_hook, NULL, 0); local_irq_disable(); In certain cases when we drop into kgdb (like with sysrq-g on a serial console) we'll get a big yell that looks like: sysrq: SysRq : DEBUG ------------[ cut here ]------------ DEBUG_LOCKS_WARN_ON(current->hardirq_context) WARNING: CPU: 0 PID: 0 at .../kernel/locking/lockdep.c:2875 lockdep_hardirqs_on+0xf0/0x160 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.0 #27 pstate: 604003c9 (nZCv DAIF +PAN -UAO) pc : lockdep_hardirqs_on+0xf0/0x160 ... Call trace: lockdep_hardirqs_on+0xf0/0x160 trace_hardirqs_on+0x188/0x1ac kgdb_roundup_cpus+0x14/0x3c kgdb_cpu_enter+0x53c/0x5cc kgdb_handle_exception+0x180/0x1d4 kgdb_compiled_brk_fn+0x30/0x3c brk_handler+0x134/0x178 do_debug_exception+0xfc/0x178 el1_dbg+0x18/0x78 kgdb_breakpoint+0x34/0x58 sysrq_handle_dbg+0x54/0x5c __handle_sysrq+0x114/0x21c handle_sysrq+0x30/0x3c qcom_geni_serial_isr+0x2dc/0x30c ... ... irq event stamp: ...45 hardirqs last enabled at (...44): [...] __do_softirq+0xd8/0x4e4 hardirqs last disabled at (...45): [...] el1_irq+0x74/0x130 softirqs last enabled at (...42): [...] _local_bh_enable+0x2c/0x34 softirqs last disabled at (...43): [...] irq_exit+0xa8/0x100 ---[ end trace adf21f830c46e638 ]--- Let's add kgdb to the list of reasons not to warn in smp_call_function_many(). That will allow us (in a future patch) to stop calling local_irq_enable() which will get rid of the original splat. NOTE: with this change comes the obvious question: will we start deadlocking more often now when we drop into the debugger. I can't say that for sure one way or the other, but the fact that we do the same logic for "oops_in_progress" makes me feel like it shouldn't happen too often. Also note that the old logic of turning on interrupts temporarily wasn't exactly safe since (I presume) that could have violated spin_lock_irqsave() semantics and ended up with a deadlock of its own. Signed-off-by: Douglas Anderson --- kernel/smp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/smp.c b/kernel/smp.c index 163c451af42e..bb581e58c8dc 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "smpboot.h" @@ -413,7 +414,8 @@ void smp_call_function_many(const struct cpumask *mask, * can't happen. */ WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() - && !oops_in_progress && !early_boot_irqs_disabled); + && !oops_in_progress && !early_boot_irqs_disabled + && !in_dbg_master()); /* Try to fastpath. So, what's a CPU they want? Ignoring this one. */ cpu = cpumask_first_and(mask, cpu_online_mask); From patchwork Mon Oct 29 18:07:07 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 10659955 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E97E71734 for ; Mon, 29 Oct 2018 18:08:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D5A5129C45 for ; Mon, 29 Oct 2018 18:08:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C663029C4A; Mon, 29 Oct 2018 18:08:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1339729C45 for ; Mon, 29 Oct 2018 18:08:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728438AbeJ3C61 (ORCPT ); Mon, 29 Oct 2018 22:58:27 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:40245 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728367AbeJ3C6V (ORCPT ); Mon, 29 Oct 2018 22:58:21 -0400 Received: by mail-pf1-f195.google.com with SMTP id g21-v6so4426614pfi.7 for ; Mon, 29 Oct 2018 11:08:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=CroHCjy2cXyW18SnvnT99u56hhAhS32VgKvRG9qriMk=; b=Adw2RJawkgnaC/jpDoSz7kz4ztVYqXNmBSnL2SvigdwN21Qq4qG0Pe+1/1PrUPKs9S bDz7ozuAXF3qkF3GBazKl/rEQgxQHcyekO1KrYK9RL32KkbqUTGP8wOmE1NGu3DekUXx VI2tl0dPwLK1ovDongsGFEfW+cu+jec5xtADY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CroHCjy2cXyW18SnvnT99u56hhAhS32VgKvRG9qriMk=; b=ddTl4G46TbQpW9BhcNQ39hACeXxSS6ef0OwljRUXJWuaHTHdW8bn8x2VO+h+e6CR45 aGWZUIj/XYl4yTUR8Mjq662XjTMDXsGBM0yEcIMZ9PK2eeTtiMP7n1wvQ8aT5gcAsojw beV+ch1Jj0tqEnM2oJKft+yAX4hopx4GpHGsJGfGobWk8Sg+wZjJyGBmKj0zNivNCUxL gawL69134NajbC2nldqRmvzKUyyBy4sT8O1uOpj4vDIU4NS3ND5Lp4Qp+0e2iiYqCrjR bSsJ+hDLYeCeW1ucCDyFacLjfQoYMqqVfinOrPk0jlUMCRz8bIXLjo4Y0CeItsB6n01r aszg== X-Gm-Message-State: AGRZ1gKUu02/mupa3pZoqZpx11mJSlhN7c8xN+kFpZuQoAsHuKDFJM/W 4Z4oTp3FxyQy9wRWITnbFoxgGA== X-Google-Smtp-Source: AJdET5d1BEiS9eVnpREP9GcY6nBDc+TgRpo6cR3NLiALJXXRpfCKZMOIAtRRC3z9kZ0u7UVM6sOi9A== X-Received: by 2002:a62:a50d:: with SMTP id v13-v6mr16095653pfm.18.1540836517190; Mon, 29 Oct 2018 11:08:37 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:c8e0:70d7:4be7:a36]) by smtp.gmail.com with ESMTPSA id u13-v6sm20537765pgp.18.2018.10.29.11.08.34 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 29 Oct 2018 11:08:35 -0700 (PDT) From: Douglas Anderson To: Jason Wessel , Daniel Thompson , tglx@linutronix.de, mingo@kernel.org, gregkh@linuxfoundation.org Cc: linux-arm-msm@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, Douglas Anderson , kstewart@linuxfoundation.org, linux-mips@linux-mips.org, dalias@libc.org, linux-sh@vger.kernel.org, benh@kernel.crashing.org, will.deacon@arm.com, linux-kernel@vger.kernel.org, mhocko@suse.com, paulus@samba.org, hpa@zytor.com, sparclinux@vger.kernel.org, linux-hexagon@vger.kernel.org, sfr@canb.auug.org.au, ysato@users.sourceforge.jp, mpe@ellerman.id.au, x86@kernel.org, linux@armlinux.org.uk, mingo@redhat.com, catalin.marinas@arm.com, jhogan@kernel.org, linux-snps-arc@lists.infradead.org, ying.huang@intel.com, rppt@linux.vnet.ibm.com, bp@alien8.de, linux-arm-kernel@lists.infradead.org, christophe.leroy@c-s.fr, pombredanne@nexb.com, ralf@linux-mips.org, rkuo@codeaurora.org, paul.burton@mips.com, vgupta@synopsys.com, akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, davem@davemloft.net Subject: [PATCH 7/7] kgdb: Remove irq flags and local_irq_enable/disable from roundup Date: Mon, 29 Oct 2018 11:07:07 -0700 Message-Id: <20181029180707.207546-8-dianders@chromium.org> X-Mailer: git-send-email 2.19.1.568.g152ad8e336-goog In-Reply-To: <20181029180707.207546-1-dianders@chromium.org> References: <20181029180707.207546-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The function kgdb_roundup_cpus() was passed a parameter that was documented as: > the flags that will be used when restoring the interrupts. There is > local_irq_save() call before kgdb_roundup_cpus(). Nobody used those flags. Anyone who wanted to temporarily turn on interrupts just did local_irq_enable() and local_irq_disable() without looking at them. So we can definitely remove the flags. Speaking of calling local_irq_enable(), it seems like a bad idea and it caused a nice splat on my system with lockdep turned on. Specifically it hit: DEBUG_LOCKS_WARN_ON(current->hardirq_context) See the previous patch in this series ("smp: Don't yell about IRQs disabled in kgdb_roundup_cpus()") for more details, but the last few things on the stack were this on my arm64 board: lockdep_hardirqs_on+0xf0/0x160 trace_hardirqs_on+0x188/0x1ac kgdb_roundup_cpus+0x14/0x3c As agrued in the the commit text of ("smp: Don't yell about IRQs disabled in kgdb_roundup_cpus()"), it seems better to make smp_call_function() lenient about kgdb than to locally turn on IRQs here. Thus let's totally remove all the local_irq_enable() and local_irq_disable() calls from all of the kgdb_roundup_cpus() calls. Signed-off-by: Douglas Anderson --- arch/arc/kernel/kgdb.c | 4 +--- arch/arm/kernel/kgdb.c | 4 +--- arch/arm64/kernel/kgdb.c | 4 +--- arch/hexagon/kernel/kgdb.c | 11 ++--------- arch/mips/kernel/kgdb.c | 4 +--- arch/powerpc/kernel/kgdb.c | 2 +- arch/sh/kernel/kgdb.c | 4 +--- arch/sparc/kernel/smp_64.c | 2 +- arch/x86/kernel/kgdb.c | 9 ++------- include/linux/kgdb.h | 9 ++------- kernel/debug/debug_core.c | 2 +- 11 files changed, 14 insertions(+), 41 deletions(-) diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c index 9a3c34af2ae8..d94d3cb7f9e8 100644 --- a/arch/arc/kernel/kgdb.c +++ b/arch/arc/kernel/kgdb.c @@ -197,11 +197,9 @@ static void kgdb_call_nmi_hook(void *ignored) kgdb_nmicallback(raw_smp_processor_id(), NULL); } -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { - local_irq_enable(); smp_call_function(kgdb_call_nmi_hook, NULL, 0); - local_irq_disable(); } struct kgdb_arch arch_kgdb_ops = { diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c index caa0dbe3dc61..a80e9259f7e9 100644 --- a/arch/arm/kernel/kgdb.c +++ b/arch/arm/kernel/kgdb.c @@ -175,11 +175,9 @@ static void kgdb_call_nmi_hook(void *ignored) kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); } -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { - local_irq_enable(); smp_call_function(kgdb_call_nmi_hook, NULL, 0); - local_irq_disable(); } static int __kgdb_notify(struct die_args *args, unsigned long cmd) diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index a20de58061a8..5d171c26788f 100644 --- a/arch/arm64/kernel/kgdb.c +++ b/arch/arm64/kernel/kgdb.c @@ -289,11 +289,9 @@ static void kgdb_call_nmi_hook(void *ignored) kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); } -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { - local_irq_enable(); smp_call_function(kgdb_call_nmi_hook, NULL, 0); - local_irq_disable(); } static int __kgdb_notify(struct die_args *args, unsigned long cmd) diff --git a/arch/hexagon/kernel/kgdb.c b/arch/hexagon/kernel/kgdb.c index 16c24b22d0b2..30fbc491cf45 100644 --- a/arch/hexagon/kernel/kgdb.c +++ b/arch/hexagon/kernel/kgdb.c @@ -119,17 +119,12 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) /** * kgdb_roundup_cpus - Get other CPUs into a holding pattern - * @flags: Current IRQ state * * On SMP systems, we need to get the attention of the other CPUs * and get them be in a known state. This should do what is needed * to get the other CPUs to call kgdb_wait(). Note that on some arches, * the NMI approach is not used for rounding up all the CPUs. For example, - * in case of MIPS, smp_call_function() is used to roundup CPUs. In - * this case, we have to make sure that interrupts are enabled before - * calling smp_call_function(). The argument to this function is - * the flags that will be used when restoring the interrupts. There is - * local_irq_save() call before kgdb_roundup_cpus(). + * in case of MIPS, smp_call_function() is used to roundup CPUs. * * On non-SMP systems, this is not called. */ @@ -139,11 +134,9 @@ static void hexagon_kgdb_nmi_hook(void *ignored) kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); } -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { - local_irq_enable(); smp_call_function(hexagon_kgdb_nmi_hook, NULL, 0); - local_irq_disable(); } #endif diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c index eb6c0d582626..6671a279966f 100644 --- a/arch/mips/kernel/kgdb.c +++ b/arch/mips/kernel/kgdb.c @@ -219,11 +219,9 @@ static void kgdb_call_nmi_hook(void *ignored) set_fs(old_fs); } -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { - local_irq_enable(); smp_call_function(kgdb_call_nmi_hook, NULL, 0); - local_irq_disable(); } static int compute_signal(int tt) diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c index 59c578f865aa..b0e804844be0 100644 --- a/arch/powerpc/kernel/kgdb.c +++ b/arch/powerpc/kernel/kgdb.c @@ -124,7 +124,7 @@ static int kgdb_call_nmi_hook(struct pt_regs *regs) } #ifdef CONFIG_SMP -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { smp_send_debugger_break(); } diff --git a/arch/sh/kernel/kgdb.c b/arch/sh/kernel/kgdb.c index 4f04c6638a4d..86b3ea927e42 100644 --- a/arch/sh/kernel/kgdb.c +++ b/arch/sh/kernel/kgdb.c @@ -319,11 +319,9 @@ static void kgdb_call_nmi_hook(void *ignored) kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); } -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { - local_irq_enable(); smp_call_function(kgdb_call_nmi_hook, NULL, 0); - local_irq_disable(); } static int __kgdb_notify(struct die_args *args, unsigned long cmd) diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c index 4792e08ad36b..f45d876983f1 100644 --- a/arch/sparc/kernel/smp_64.c +++ b/arch/sparc/kernel/smp_64.c @@ -1014,7 +1014,7 @@ void flush_dcache_page_all(struct mm_struct *mm, struct page *page) } #ifdef CONFIG_KGDB -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { smp_cross_call(&xcall_kgdb_capture, 0, 0, 0); } diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c index 8e36f249646e..ac6291a4178d 100644 --- a/arch/x86/kernel/kgdb.c +++ b/arch/x86/kernel/kgdb.c @@ -422,21 +422,16 @@ static void kgdb_disable_hw_debug(struct pt_regs *regs) #ifdef CONFIG_SMP /** * kgdb_roundup_cpus - Get other CPUs into a holding pattern - * @flags: Current IRQ state * * On SMP systems, we need to get the attention of the other CPUs * and get them be in a known state. This should do what is needed * to get the other CPUs to call kgdb_wait(). Note that on some arches, * the NMI approach is not used for rounding up all the CPUs. For example, - * in case of MIPS, smp_call_function() is used to roundup CPUs. In - * this case, we have to make sure that interrupts are enabled before - * calling smp_call_function(). The argument to this function is - * the flags that will be used when restoring the interrupts. There is - * local_irq_save() call before kgdb_roundup_cpus(). + * in case of MIPS, smp_call_function() is used to roundup CPUs. * * On non-SMP systems, this is not called. */ -void kgdb_roundup_cpus(unsigned long flags) +void kgdb_roundup_cpus(void) { apic->send_IPI_allbutself(APIC_DM_NMI); } diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h index e465bb15912d..05e5b2eb0d32 100644 --- a/include/linux/kgdb.h +++ b/include/linux/kgdb.h @@ -178,21 +178,16 @@ kgdb_arch_handle_exception(int vector, int signo, int err_code, /** * kgdb_roundup_cpus - Get other CPUs into a holding pattern - * @flags: Current IRQ state * * On SMP systems, we need to get the attention of the other CPUs * and get them into a known state. This should do what is needed * to get the other CPUs to call kgdb_wait(). Note that on some arches, * the NMI approach is not used for rounding up all the CPUs. For example, - * in case of MIPS, smp_call_function() is used to roundup CPUs. In - * this case, we have to make sure that interrupts are enabled before - * calling smp_call_function(). The argument to this function is - * the flags that will be used when restoring the interrupts. There is - * local_irq_save() call before kgdb_roundup_cpus(). + * in case of MIPS, smp_call_function() is used to roundup CPUs. * * On non-SMP systems, this is not called. */ -extern void kgdb_roundup_cpus(unsigned long flags); +extern void kgdb_roundup_cpus(void); /** * kgdb_arch_set_pc - Generic call back to the program counter diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 65c0f1363788..f3cadda45f07 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -593,7 +593,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs, /* Signal the other CPUs to enter kgdb_wait() */ else if ((!kgdb_single_step) && kgdb_do_roundup) - kgdb_roundup_cpus(flags); + kgdb_roundup_cpus(); #endif /*