Re: dmar pte read access not set error messages on hp dl388 gen8 systems

[Lu Baolu <baolu.lu@linux.intel.com>]

Hi,

On 12/3/19 12:13 AM, Jerry Snitselaar wrote:
> On Mon Dec 02 19, Jerry Snitselaar wrote:
>> On Mon Dec 02 19, Lu Baolu wrote:
>>> Hi,
>>>
>>> On 12/2/19 2:34 PM, Jerry Snitselaar wrote:
>>>> We are seeing DMAR PTE read access not set errors when booting a
>>>> kernel with default passthrough, both with a test kernel and with
>>>> a 5.4.0 kernel. Previously we would see a number of identity mappings
>>>> being set related to the rmrrs, and now they aren't seen and we get
>>>> the dmar pte errors as devices touch those regions. From what I can 
>>>> tell
>>>> currently df4f3c603aeb ("iommu/vt-d: Remove static identity map code")
>>>> removed the bit of code in init_dmars that used to set up those
>>>> mappings:
>>>>
>>>> -       /*
>>>> -        * For each rmrr
>>>> -        *   for each dev attached to rmrr
>>>> -        *   do
>>>> -        *     locate drhd for dev, alloc domain for dev
>>>> -        *     allocate free domain
>>>> -        *     allocate page table entries for rmrr
>>>> -        *     if context not allocated for bus
>>>> -        *           allocate and init context
>>>> -        *           set present in root table for this bus
>>>> -        *     init context with domain, translation etc
>>>> -        *    endfor
>>>> -        * endfor
>>>> -        */
>>>> -       pr_info("Setting RMRR:\n");
>>>> -       for_each_rmrr_units(rmrr) {
>>>> -               /* some BIOS lists non-exist devices in DMAR table. */
>>>> -               for_each_active_dev_scope(rmrr->devices, 
>>>> rmrr->devices_cnt,
>>>> -                                         i, dev) {
>>>> -                       ret = iommu_prepare_rmrr_dev(rmrr, dev);
>>>> -                       if (ret)
>>>> -                               pr_err("Mapping reserved region 
>>>> failed\n");
>>>> -               }
>>>> -       }
>>>>
>>>> si_domain_init now has code that sets identity maps for devices in 
>>>> rmrrs, but
>>>> only for certain devices.
>>>
>>> On which device, are you seeing this error? Is it a rmrr locked device?
>>>
>>> Best regards,
>>> baolu
>>>
>>
>> Almost all of the messages are for the ilo, but there also is a 
>> message for
>> the smart array raid bus controller.
>>
> 
> Also seeing it with a dl380 gen9 system, where the raid bus controller
> is getting the error.

Does it help if you remove

                         if (device_is_rmrr_locked(dev))
                                 continue;

in si_domain_init()?

Best regards,
baolu
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