Re: Need arm64/qemu help

[Ian Arkver <ian.arkver.dev@gmail.com>]

On 03/03/18 10:51, Ian Arkver wrote:
> On 03/03/18 09:00, Richard Purdie wrote:
>> Hi,
>>
>> I need some help with a problem we keep seeing:
>>
>> https://autobuilder.yocto.io/builders/nightly-arm64/builds/798
>>
>> Basically, now and again, for reasons we don't understand, all the
>> sanity tests fail for qemuarm64.
>>
>> I've poked at this a bit and if I go in onto the failed machine and run
>> this again, they work, using the same image, kernel and qemu binaries.
>> We've seen this on two different autobuilder infrastructure on varying
>> host OSs. They always seem to fail all three at once.
>>
>> Whilst this was a mut build, I saw this repeat three builds in a row on
>> the new autobuilder we're setting up with master.
>>
>> The kernels always seem to hang somewhere around the:
>>
>> | [    0.766079] raid6: int64x1  xor()   302 MB/s
>> | [    0.844597] raid6: int64x2  gen()   675 MB/s
> 
> I believe this is related to btrfs and comes from having btrfs compiled 
> in to the kernel. You could maybe side-step the problem (and hence leave 
> it lurking) by changing btrfs to a module.

Actually, this comes from a library (lib/raid6), and in 4.14.y's arm64 
defconfig BTRFS is already a module, so please disregard my hack suggestion.

> Regards,
> Ian
> 
>> raid timing measurements.
>>
>> In the past we've dived in and handled these kinds of things but I've
>> run out of people to lean on and I need help from the wider community.
>>
>> Can anyone help look into and fix this?
>>
>> This is serious as if nobody cares, I'll have to simply stop boot
>> testing qemuarm64.
>>
>> Not sure if there is an open bug yet either :/.
>>
>> Cheers,
>>
>> Richard
>>