From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751804AbWFAGOR (ORCPT ); Thu, 1 Jun 2006 02:14:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751810AbWFAGOR (ORCPT ); Thu, 1 Jun 2006 02:14:17 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:223 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1751804AbWFAGOR (ORCPT ); Thu, 1 Jun 2006 02:14:17 -0400 Date: Thu, 1 Jun 2006 08:14:40 +0200 From: Ingo Molnar To: Andrew Morton Cc: "Randy.Dunlap" , linux-kernel@vger.kernel.org Subject: Re: 2.6.17-rc5-mm1 Message-ID: <20060601061440.GA19236@elte.hu> References: <20060530022925.8a67b613.akpm@osdl.org> <20060531182507.aaf1f9fd.rdunlap@xenotime.net> <20060531184302.9e79f518.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060531184302.9e79f518.akpm@osdl.org> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: -3.1 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-3.1 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_50 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts 0.0 BAYES_50 BODY: Bayesian spam probability is 40 to 60% [score: 0.5000] 0.2 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Andrew Morton wrote: > > [ 36.489028] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP: > > [ 36.500245] [<0000000000000000>] stext+0x7feff0e8/0xe8 > > [ 37.103370] Call Trace: > > [ 37.140640] [] do_IRQ+0x4f/0x5e > > [ 37.167285] [] mwait_idle+0x0/0x53 > > [ 37.193322] [] ret_from_intr+0x0/0xa > > [ 37.219723] Randy, do you have an MSI-X device perhaps? Could you try the patch below? Ingo ------------------------------------------------------ Subject: genirq MSI fixes From: Ingo Molnar This is a fixed up and cleaned up replacement for genirq-msi-fixes.patch, which should solve the i386 4KSTACKS problem. I also added Ben's idea of pushing the __do_IRQ() check into generic_handle_irq(). I booted this with MSI enabled, but i only have MSI devices, not MSI-X devices. I'd still expect MSI-X to work now. irqchip migration helper: call __do_IRQ() if a descriptor is attached to an irqtype-style controller. This also fixes MSI-X IRQ handling on i386 and x86_64. Signed-off-by: Ingo Molnar Cc: Thomas Gleixner Cc: Benjamin Herrenschmidt Cc: Roland Dreier Signed-off-by: Andrew Morton --- arch/i386/kernel/irq.c | 5 +++++ include/linux/irq.h | 27 ++++++++++++++++----------- 2 files changed, 21 insertions(+), 11 deletions(-) diff -puN arch/i386/kernel/irq.c~genirq-msi-fixes-2 arch/i386/kernel/irq.c --- devel/arch/i386/kernel/irq.c~genirq-msi-fixes-2 2006-05-30 23:47:30.000000000 -0700 +++ devel-akpm/arch/i386/kernel/irq.c 2006-05-30 23:47:30.000000000 -0700 @@ -77,6 +77,10 @@ fastcall unsigned int do_IRQ(struct pt_r } #endif + if (!irq_desc[irq].handle_irq) { + __do_IRQ(irq, regs); + goto out_exit; + } #ifdef CONFIG_4KSTACKS curctx = (union irq_ctx *) current_thread_info(); @@ -109,6 +113,7 @@ fastcall unsigned int do_IRQ(struct pt_r #endif desc->handle_irq(irq, desc, regs); +out_exit: irq_exit(); return 1; diff -puN include/linux/irq.h~genirq-msi-fixes-2 include/linux/irq.h --- devel/include/linux/irq.h~genirq-msi-fixes-2 2006-05-30 23:47:30.000000000 -0700 +++ devel-akpm/include/linux/irq.h 2006-05-30 23:47:30.000000000 -0700 @@ -176,17 +176,6 @@ typedef struct irq_desc irq_desc_t; */ #include -/* - * Architectures call this to let the generic IRQ layer - * handle an interrupt: - */ -static inline void generic_handle_irq(unsigned int irq, struct pt_regs *regs) -{ - struct irq_desc *desc = irq_desc + irq; - - desc->handle_irq(irq, desc, regs); -} - extern int setup_irq(unsigned int irq, struct irqaction *new); #ifdef CONFIG_GENERIC_HARDIRQS @@ -324,6 +313,22 @@ handle_irq_name(void fastcall (*handle)( */ extern fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs); +/* + * Architectures call this to let the generic IRQ layer + * handle an interrupt. If the descriptor is attached to an + * irqchip-style controller then we call the ->handle_irq() handler, + * and it calls __do_IRQ() if it's attached to an irqtype-style controller. + */ +static inline void generic_handle_irq(unsigned int irq, struct pt_regs *regs) +{ + struct irq_desc *desc = irq_desc + irq; + + if (likely(desc->handle_irq)) + desc->handle_irq(irq, desc, regs); + else + __do_IRQ(irq, regs); +} + /* Handling of unhandled and spurious interrupts: */ extern void note_interrupt(unsigned int irq, struct irq_desc *desc, int action_ret, struct pt_regs *regs); _