From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752356Ab2LTSmJ (ORCPT ); Thu, 20 Dec 2012 13:42:09 -0500 Received: from gate.crashing.org ([63.228.1.57]:39069 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752065Ab2LTSmB convert rfc822-to-8bit (ORCPT ); Thu, 20 Dec 2012 13:42:01 -0500 Subject: Re: [v1][PATCH 3/6] book3e/kgdb: update thread's dbcr0 Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii From: Kumar Gala In-Reply-To: <1355994510-11934-4-git-send-email-tiejun.chen@windriver.com> Date: Thu, 20 Dec 2012 12:41:53 -0600 Cc: , , , Content-Transfer-Encoding: 8BIT Message-Id: References: <1355994510-11934-1-git-send-email-tiejun.chen@windriver.com> <1355994510-11934-4-git-send-email-tiejun.chen@windriver.com> To: Tiejun Chen X-Mailer: Apple Mail (2.1278) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Dec 20, 2012, at 3:08 AM, Tiejun Chen wrote: > gdb always need to generate a single step properly to invoke > a kgdb state. But with lazy interrupt, book3e can't always > trigger a debug exception with a single step since the current > is blocked for handling those pending exception, then we miss > that expected dbcr configuration at last to generate a debug > exception. > > So here we also update thread's dbcr0 to make sure the current > can go back with that missed dbcr0 configuration. > > Signed-off-by: Tiejun Chen > --- > arch/powerpc/kernel/kgdb.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c > index c470a40..516b44b 100644 > --- a/arch/powerpc/kernel/kgdb.c > +++ b/arch/powerpc/kernel/kgdb.c > @@ -426,8 +426,18 @@ int kgdb_arch_handle_exception(int vector, int signo, int err_code, > /* set the trace bit if we're stepping */ > if (remcom_in_buffer[0] == 's') { > #ifdef CONFIG_PPC_ADV_DEBUG_REGS > +#ifdef CONFIG_PPC_BOOK3E Should this really be CONFIG_PPC64 or CONFIG_PPC_BOOK3E_64? > + /* With lazy interrut we have to update thread dbcr0 here > + * to make sure we can set debug properly at last to invoke > + * kgdb again to work well. > + */ > + current->thread.dbcr0 = > + mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM; > + mtspr(SPRN_DBCR0, current->thread.dbcr0); > +#else > mtspr(SPRN_DBCR0, > mfspr(SPRN_DBCR0) | DBCR0_IC | DBCR0_IDM); > +#endif Can we code this so we don't need the #else? > linux_regs->msr |= MSR_DE; > #else > linux_regs->msr |= MSR_SE; > -- > 1.7.9.5 > > -- > 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/