Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757431Ab3ENNRN (ORCPT ); Tue, 14 May 2013 09:17:13 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:20562 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755970Ab3ENNRJ (ORCPT ); Tue, 14 May 2013 09:17:09 -0400 Date: Tue, 14 May 2013 09:17:04 -0400 From: Konrad Rzeszutek Wilk To: Igor Mammedov Cc: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, chuck.anderson@oracle.com Subject: Re: [PATCH 2/2] cpu: make sure that cpu/online file created before KOBJ_ADD is emitted Message-ID: <20130514131704.GE5558@phenom.dumpdata.com> References: <20130513133128.GJ6811@phenom.dumpdata.com> <1368482732-25554-3-git-send-email-imammedo@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1368482732-25554-3-git-send-email-imammedo@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3015 Lines: 95 On Tue, May 14, 2013 at 12:05:32AM +0200, Igor Mammedov wrote: > Fixes race between udev and hotplugged CPU registration, described at > https://lkml.org/lkml/2012/4/30/198 It would be better if you copy-n-pasted the contents of that URL in here. > by defining "online" attribute statically so that device_add() would > create it before notifying udev about new CPU. > > Signed-off-by: Igor Mammedov > --- > drivers/base/cpu.c | 34 +++++++++++++++++++++------------- > 1 files changed, 21 insertions(+), 13 deletions(-) > > diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c > index 02e4d73..6578030 100644 > --- a/drivers/base/cpu.c > +++ b/drivers/base/cpu.c > @@ -64,18 +64,21 @@ static ssize_t __ref store_online(struct device *dev, > } > static DEVICE_ATTR(online, 0644, show_online, store_online); > > -static void __cpuinit register_cpu_control(struct cpu *cpu) > -{ > - device_create_file(&cpu->dev, &dev_attr_online); > -} > +static struct attribute *hotplug_cpu_attrs[] = { > + &dev_attr_online.attr, > + NULL > +}; > + > +static struct attribute_group hotplug_cpu_attr_group = { > + .attrs = hotplug_cpu_attrs, > +}; > + > void unregister_cpu(struct cpu *cpu) > { > int logical_cpu = cpu->dev.id; > > unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu)); > > - device_remove_file(&cpu->dev, &dev_attr_online); > - > device_unregister(&cpu->dev); > per_cpu(cpu_sys_devices, logical_cpu) = NULL; > return; > @@ -101,11 +104,6 @@ static ssize_t cpu_release_store(struct device *dev, > static DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store); > static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store); > #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ > - > -#else /* ... !CONFIG_HOTPLUG_CPU */ > -static inline void register_cpu_control(struct cpu *cpu) > -{ > -} > #endif /* CONFIG_HOTPLUG_CPU */ > > #ifdef CONFIG_KEXEC > @@ -150,6 +148,16 @@ static const struct attribute_group *common_cpu_attr_groups[] = { > NULL > }; > > +static const struct attribute_group *hotplugable_cpu_attr_groups[] = { > +#ifdef CONFIG_KEXEC > + &crash_note_cpu_attr_group, > +#endif > +#ifdef CONFIG_HOTPLUG_CPU > + &hotplug_cpu_attr_group, > +#endif > + NULL > +}; > + > /* > * Print cpu online, possible, present, and system maps > */ > @@ -265,9 +273,9 @@ int __cpuinit register_cpu(struct cpu *cpu, int num) > cpu->dev.bus->uevent = arch_cpu_uevent; > #endif > cpu->dev.groups = common_cpu_attr_groups; > + if (cpu->hotpluggable) > + cpu->dev.groups = hotplugable_cpu_attr_groups; > error = device_register(&cpu->dev); > - if (!error && cpu->hotpluggable) > - register_cpu_control(cpu); > if (!error) > per_cpu(cpu_sys_devices, num) = &cpu->dev; > if (!error) > -- > 1.7.1 > -- 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/