Re: [Xen-devel] [PATCH 1/2] AMD IOMMU: also spot missing IO-APIC entries in IVRS table

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 06.02.13 at 16:03, Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> wrote:
> On 2/6/2013 9:52 AM, Jan Beulich wrote:
>>>>> On 06.02.13 at 15:41, Boris Ostrovsky<boris.ostrovsky@xxxxxxxxxx>  wrote:
>>> On 2/6/2013 8:12 AM, Jan Beulich wrote:
>>>
>>>>
>>>> +    /* Each IO-APIC must have been mentioned in the table. */
>>>> +    for ( apic = 0; !error&&   apic<   nr_ioapics; ++apic )
>>>> +    {
>>>> +        if ( !nr_ioapic_entries[apic] ||
>>>> +             ioapic_sbdf[IO_APIC_ID(apic)].pin_setup )
>>>> +            continue;
>>>> +
>>>> +        printk(XENLOG_ERR "IVHD Error: no information for IO-APIC %#x\n",
>>>> +               IO_APIC_ID(apic));
>>>> +        if ( amd_iommu_perdev_intremap )
>>>> +            error = -ENXIO;
>>>> +        else
>>>> +        {
>>>> +            ioapic_sbdf[IO_APIC_ID(apic)].pin_setup = xzalloc_array(
>>>> +                unsigned long, BITS_TO_LONGS(nr_ioapic_entries[apic]));
>>>> +            if ( !ioapic_sbdf[IO_APIC_ID(apic)].pin_setup )
>>>> +            {
>>>> +                printk(XENLOG_ERR "IVHD Error: Out of memory\n");
>>>> +                error = -ENOMEM;
>>>> +            }
>>>> +        }
>>>> +    }
>>>> +
>>>>        return error;
>>>>    }
>>>>
>>>
>>> Don't we end up with ioapic_sbdf[IO_APIC_ID(apic)].bdf/seg being
>>> uninitialized? They are usually set in parse_ivhd_device_special(), at
>>> the same time pin_setup is allocated, but with IVRS broken in this way
>>> we'll never get there, will we?
>>
>> Correct. .bdf/.seg being uninitialized is no much of a problem
>> when using global intremap tables though.
> 
> Since this patch has been tested it clearly must have worked somehow but 
> I don't understand where you'd get bdf and seg in 
> amd_iommu_ioapic_update_ire() and then manage to find the right IOMMU.

The "right" IOMMU simply is the only one, and that is equally well
found with sbdf being zero.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel