Re: Linux 3.4 dom0 kernel error loading xen-acpi-processor: Input/output error

["Pasi Kärkkäinen" <pasik@iki.fi>]

On Thu, Feb 21, 2013 at 07:29:13AM -0500, Konrad Rzeszutek Wilk wrote:
> On Thu, Feb 21, 2013 at 11:24:34AM +0200, Pasi Kärkkäinen wrote:
> > Hello,
> > 
> > Does anyone know why loading xen-acpi-processor driver fails like this?:
> > 
> > # modprobe xen-acpi-processor
> > FATAL: Error inserting xen_acpi_processor (/lib/modules/3.4.32-6.el6.centos.alt.x86_64/kernel/drivers/xen/xen-acpi-processor.ko): Input/output error
> > 
> > Using "modprobe -v" doesn't provide any more information about the problem.
> > Also there's nothing in dom0 kernel dmesg.
> > 
> > Hardware is Dell R510 server with Intel Xeon 5600 series CPU. 
> > Xen 4.2.1.
> > 
> > Kernel is based on 3.4.32 (so the upstream kernel.org longterm stable version) 
> > with some additional Xen patches backported from later upstream kernels. 
> > Any tips how to troubleshoot this? 
> 
> Rebuild the module and add this
> diff --git a/drivers/xen/xen-acpi-processor.c b/drivers/xen/xen-acpi-processor.c
> index 316df65..5d824a2 100644
> --- a/drivers/xen/xen-acpi-processor.c
> +++ b/drivers/xen/xen-acpi-processor.c
> @@ -16,6 +16,7 @@
>   * more details.
>   *
>   */
> +#define DEBUG 1
>  
>  #include <linux/cpumask.h>
>  #include <linux/cpufreq.h>
> 
> 
> That should help in figuring it out.
> 

This is what I get with DEBUG enabled:

# modprobe -v xen-acpi-processor
insmod /lib/modules/3.4.32-6.dbg1.el6.x86_64/kernel/drivers/xen/xen-acpi-processor.ko
FATAL: Error inserting xen_acpi_processor (/lib/modules/3.4.32-6.dbg1.el6.x86_64/kernel/drivers/xen/xen-acpi-processor.ko): Input/output error

in dom0 kernel dmesg:
xen-acpi-processor: Max ACPI ID: 24

.. and that's all.

Adding more debug options on the kernel cmdline I see this:
initcall xen_acpi_processor_init+0x0/0x6b0 [xen_acpi_processor] returned -5 after 67 usecs
initcall xen_acpi_processor_init+0x0/0x6b0 [xen_acpi_processor] returned with error code -5

And enabling some ACPI debug options:
processor_perflib-0430 [00] processor_get_performa: ACPI-based processor performance control unavailable


I added a bunch of more calls to pr_debug() in xen_acpi_processor_init() and it seems:

        /* Do initialization in ACPI core. It is OK to fail here. */
        (void)acpi_processor_preregister_performance(acpi_perf_data);

        for_each_possible_cpu(i) {
                struct acpi_processor_performance *perf;

                perf = per_cpu_ptr(acpi_perf_data, i);
                rc = acpi_processor_register_performance(perf, i);
                if (rc)
                        goto err_out;
        }

"goto err_out" is the path taken from here..
It seems acpi_processor_register_performance() returns -EIO.

.. which means in acpi_processor_register_performance()

        if (acpi_processor_get_performance_info(pr)) {
                pr->performance = NULL;
                mutex_unlock(&performance_mutex);
                return -EIO;
        }


It seems acpi_processor_get_performance_info() returns -ENODEV:

        if (ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                  "ACPI-based processor performance control unavailable\n"));
                return -ENODEV;
        }


Does this ring any bells? 

Thanks,

-- Pasi