Re: [REGRESSION] media: cx23885 broken by commit 453afdd "[media] cx23885: convert to vb2"

[Hans Verkuil <hverkuil@xs4all.nl>]

On 01/29/15 12:51, Raimonds Cicans wrote:
> On 29.01.2015 09:33, Hans Verkuil wrote:
>> On 01/11/2015 10:33 AM, Raimonds Cicans wrote:
>>> I contacted you because I am hit by regression caused by your commit:
>>> 453afdd "[media] cx23885: convert to vb2"
>>>
>>>
>>> My system:
>>> AMD Athlon(tm) II X2 240e Processor on Asus M5A97 LE R2.0 motherboard
>>> TBS6981 card (Dual DVB-S/S2 PCIe receiver, cx23885 in kernel driver)
>>>
>>> After upgrade from kernel 3.13.10 (do not have commit) to 3.17.7
>>> (have commit) I started receiving following IOMMU related messages:
>>>
>>> 1)
>>> AMD-Vi: Event logged [IO_PAGE_FAULT device=0a:00.0 domain=0x001d
>>> address=0x000000000637c000 flags=0x0000]
>>>
>>> where device=0a:00.0 is TBS6981 card
>> As far as I can tell this has nothing to do with the cx23885 driver but is
>> a bug in the amd iommu/BIOS. See e.g.:
>>
>> https://bbs.archlinux.org/viewtopic.php?pid=1309055
>>
>> I managed to reproduce the Intel equivalent if I enable CONFIG_IOMMU_SUPPORT.
>>
>> Most likely due to broken BIOS/ACPI/whatever information that's read by the
>> kernel. I would recommend disabling this kernel option.
>>
> Maybe...
> 
> But on other hand this did not happen on old kernel with old driver.
> And when I did bisection on old kernel + media tree I started to
> receive this message only on new driver.

Was CONFIG_IOMMU_SUPPORT enabled in the old kernel?

Regards,

	Hans

> And I can not disable this feature because then USB and LAN
> stop working.