Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754088Ab3CKLDK (ORCPT ); Mon, 11 Mar 2013 07:03:10 -0400 Received: from mail1.windriver.com ([147.11.146.13]:54858 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753988Ab3CKLDH (ORCPT ); Mon, 11 Mar 2013 07:03:07 -0400 From: Tiejun Chen To: , CC: , , Subject: [v4][PATCH 7/7] book3e/kgdb: Fix a single stgep case of lazy IRQ Date: Mon, 11 Mar 2013 19:02:46 +0800 Message-ID: <1362999766-20897-8-git-send-email-tiejun.chen@windriver.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1362999766-20897-1-git-send-email-tiejun.chen@windriver.com> References: <1362999766-20897-1-git-send-email-tiejun.chen@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2310 Lines: 69 When we're in kgdb_singlestep(), we have to work around to get thread_info by copying from the kernel stack before calling kgdb_handle_exception(), then copying it back afterwards. But for PPC64, we have a lazy interrupt implementation. So after copying thread info frome kernle stack, if we need to replay an interrupt, we shouldn't restore that previous backup thread info to make sure we can replay an interrupt lately with a proper thread info. This patch use __check_irq_replay() to guarantee this process. Signed-off-by: Tiejun Chen --- arch/powerpc/kernel/irq.c | 10 ++++++++++ arch/powerpc/kernel/kgdb.c | 3 ++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 4f97fe3..bb8d27a 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -339,7 +339,17 @@ bool prep_irq_for_idle(void) return true; } +notrace unsigned int check_irq_replay(void) +{ + return __check_irq_replay(); +} +#else +notrace unsigned int check_irq_replay(void) +{ + return 0; +} #endif /* CONFIG_PPC64 */ +EXPORT_SYMBOL(check_irq_replay); int arch_show_interrupts(struct seq_file *p, int prec) { diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c index cde7818..5b30408 100644 --- a/arch/powerpc/kernel/kgdb.c +++ b/arch/powerpc/kernel/kgdb.c @@ -152,6 +152,7 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs) } static DEFINE_PER_CPU(struct thread_info, kgdb_thread_info); +extern notrace unsigned int check_irq_replay(void); static int kgdb_singlestep(struct pt_regs *regs) { struct thread_info *thread_info, *exception_thread_info; @@ -181,7 +182,7 @@ static int kgdb_singlestep(struct pt_regs *regs) kgdb_handle_exception(0, SIGTRAP, 0, regs); - if (thread_info != exception_thread_info) + if ((thread_info != exception_thread_info) && (!check_irq_replay())) /* Restore current_thread_info lastly. */ memcpy(exception_thread_info, backup_current_thread_info, sizeof *thread_info); -- 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/