Messages in this thread | | | Date | Tue, 24 Feb 2009 20:36:22 +0100 | From | Ingo Molnar <> | Subject | Re: [patch 1/6] x86, ftrace, hw-branch-tracer: support hotplug cpus |
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* Markus Metzger <markus.t.metzger@intel.com> wrote:
> Support hotplug cpus.
> +static int __cpuinit bts_hotcpu_handler(struct notifier_block *nfb, > + unsigned long action, void *hcpu) > +{ > + unsigned int cpu = (unsigned long)hcpu; > + > + mutex_lock(&bts_tracer_mutex);
This is buggy: CPU hotplug handlers must not sleep (they are called with irqs disabled), while this code does a mutex_lock() which can sleep.
Ingo
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