From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail1.windriver.com (mail1.windriver.com [147.11.146.13]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mail1.windriver.com", Issuer "Intel External Basic Issuing CA 3A" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 49F782C0109 for ; Mon, 21 Jan 2013 18:44:33 +1100 (EST) From: Tiejun Chen To: , Subject: [v2][PATCH 4/6] book3e/kgdb: Fix a single stgep case of lazy IRQ Date: Mon, 21 Jan 2013 15:44:13 +0800 Message-ID: <1358754255-31484-5-git-send-email-tiejun.chen@windriver.com> In-Reply-To: <1358754255-31484-1-git-send-email-tiejun.chen@windriver.com> References: <1358754255-31484-1-git-send-email-tiejun.chen@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, jason.wessel@windriver.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 eb30a40..2f22807 100644 --- a/arch/powerpc/kernel/kgdb.c +++ b/arch/powerpc/kernel/kgdb.c @@ -151,6 +151,7 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs) return 1; } +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