From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48938 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752576AbbFCBRM (ORCPT ); Tue, 2 Jun 2015 21:17:12 -0400 Subject: Patch "xen/events: don't bind non-percpu VIRQs with percpu chip" has been added to the 4.0-stable tree To: david.vrabel@citrix.com, gregkh@linuxfoundation.org Cc: , From: Date: Wed, 03 Jun 2015 10:15:13 +0900 Message-ID: <143329411312545@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled xen/events: don't bind non-percpu VIRQs with percpu chip to the 4.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xen-events-don-t-bind-non-percpu-virqs-with-percpu-chip.patch and it can be found in the queue-4.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 77bb3dfdc0d554befad58fdefbc41be5bc3ed38a Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Tue, 19 May 2015 18:40:49 +0100 Subject: xen/events: don't bind non-percpu VIRQs with percpu chip From: David Vrabel commit 77bb3dfdc0d554befad58fdefbc41be5bc3ed38a upstream. A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different VCPU than it is bound to. This can result in a race between handle_percpu_irq() and removing the action in __free_irq() because handle_percpu_irq() does not take desc->lock. The interrupt handler sees a NULL action and oopses. Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER). # cat /proc/interrupts | grep virq 40: 87246 0 xen-percpu-virq timer0 44: 0 0 xen-percpu-virq debug0 47: 0 20995 xen-percpu-virq timer1 51: 0 0 xen-percpu-virq debug1 69: 0 0 xen-dyn-virq xen-pcpu 74: 0 0 xen-dyn-virq mce 75: 29 0 xen-dyn-virq hvc_console Signed-off-by: David Vrabel Signed-off-by: Greg Kroah-Hartman --- drivers/tty/hvc/hvc_xen.c | 2 +- drivers/xen/events/events_base.c | 12 ++++++++---- include/xen/events.h | 2 +- 3 files changed, 10 insertions(+), 6 deletions(-) --- a/drivers/tty/hvc/hvc_xen.c +++ b/drivers/tty/hvc/hvc_xen.c @@ -289,7 +289,7 @@ static int xen_initial_domain_console_in return -ENOMEM; } - info->irq = bind_virq_to_irq(VIRQ_CONSOLE, 0); + info->irq = bind_virq_to_irq(VIRQ_CONSOLE, 0, false); info->vtermno = HVC_COOKIE; spin_lock(&xencons_lock); --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -957,7 +957,7 @@ unsigned xen_evtchn_nr_channels(void) } EXPORT_SYMBOL_GPL(xen_evtchn_nr_channels); -int bind_virq_to_irq(unsigned int virq, unsigned int cpu) +int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu) { struct evtchn_bind_virq bind_virq; int evtchn, irq, ret; @@ -971,8 +971,12 @@ int bind_virq_to_irq(unsigned int virq, if (irq < 0) goto out; - irq_set_chip_and_handler_name(irq, &xen_percpu_chip, - handle_percpu_irq, "virq"); + if (percpu) + irq_set_chip_and_handler_name(irq, &xen_percpu_chip, + handle_percpu_irq, "virq"); + else + irq_set_chip_and_handler_name(irq, &xen_dynamic_chip, + handle_edge_irq, "virq"); bind_virq.virq = virq; bind_virq.vcpu = cpu; @@ -1062,7 +1066,7 @@ int bind_virq_to_irqhandler(unsigned int { int irq, retval; - irq = bind_virq_to_irq(virq, cpu); + irq = bind_virq_to_irq(virq, cpu, irqflags & IRQF_PERCPU); if (irq < 0) return irq; retval = request_irq(irq, handler, irqflags, devname, dev_id); --- a/include/xen/events.h +++ b/include/xen/events.h @@ -17,7 +17,7 @@ int bind_evtchn_to_irqhandler(unsigned i irq_handler_t handler, unsigned long irqflags, const char *devname, void *dev_id); -int bind_virq_to_irq(unsigned int virq, unsigned int cpu); +int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu); int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, irq_handler_t handler, unsigned long irqflags, const char *devname, Patches currently in stable-queue which might be from david.vrabel@citrix.com are queue-4.0/xen-events-don-t-bind-non-percpu-virqs-with-percpu-chip.patch