Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A488C433FE for ; Wed, 24 Nov 2021 13:00:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245273AbhKXND6 (ORCPT ); Wed, 24 Nov 2021 08:03:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:39966 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347660AbhKXNBc (ORCPT ); Wed, 24 Nov 2021 08:01:32 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5C4AF619EA; Wed, 24 Nov 2021 12:35:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637757308; bh=2Fz1alJR0sRa2U93z50qxHzPvVUeyZ90gC0q24iS+fI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SdkX5tPj+GpDZyn3NTh9jCIODMrR/s9iTxUKJSfk97NBFAuNC2kONhfB+QAYL0v0t RquAoju1eAt55pNPUhdC95eLfH0Osv2pdbW28mCb79cO6Hkddru4DMnKq3VUiROIcC UVzsudsOeh4aJWHI9+oGlvX21CKGZhQD5ojgMSlk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sven Schnelle , Helge Deller , Sasha Levin Subject: [PATCH 4.19 126/323] parisc/kgdb: add kgdb_roundup() to make kgdb work with idle polling Date: Wed, 24 Nov 2021 12:55:16 +0100 Message-Id: <20211124115723.190249898@linuxfoundation.org> X-Mailer: git-send-email 2.34.0 In-Reply-To: <20211124115718.822024889@linuxfoundation.org> References: <20211124115718.822024889@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sven Schnelle [ Upstream commit 66e29fcda1824f0427966fbee2bd2c85bf362c82 ] With idle polling, IPIs are not sent when a CPU idle, but queued and run later from do_idle(). The default kgdb_call_nmi_hook() implementation gets the pointer to struct pt_regs from get_irq_reqs(), which doesn't work in that case because it was not called from the IPI interrupt handler. Fix it by defining our own kgdb_roundup() function which sents an IPI_ENTER_KGDB. When that IPI is received on the target CPU kgdb_nmicallback() is called. Signed-off-by: Sven Schnelle Signed-off-by: Helge Deller Signed-off-by: Sasha Levin --- arch/parisc/kernel/smp.c | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c index 5e26dbede5fc2..ae4fc8769c38b 100644 --- a/arch/parisc/kernel/smp.c +++ b/arch/parisc/kernel/smp.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -74,7 +75,10 @@ enum ipi_message_type { IPI_CALL_FUNC, IPI_CPU_START, IPI_CPU_STOP, - IPI_CPU_TEST + IPI_CPU_TEST, +#ifdef CONFIG_KGDB + IPI_ENTER_KGDB, +#endif }; @@ -170,7 +174,12 @@ ipi_interrupt(int irq, void *dev_id) case IPI_CPU_TEST: smp_debug(100, KERN_DEBUG "CPU%d is alive!\n", this_cpu); break; - +#ifdef CONFIG_KGDB + case IPI_ENTER_KGDB: + smp_debug(100, KERN_DEBUG "CPU%d ENTER_KGDB\n", this_cpu); + kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); + break; +#endif default: printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n", this_cpu, which); @@ -226,6 +235,12 @@ send_IPI_allbutself(enum ipi_message_type op) } } +#ifdef CONFIG_KGDB +void kgdb_roundup_cpus(void) +{ + send_IPI_allbutself(IPI_ENTER_KGDB); +} +#endif inline void smp_send_stop(void) { send_IPI_allbutself(IPI_CPU_STOP); } -- 2.33.0