Re: Yocto Project Status WW47’17

[Robert Yang <liezhi.yang@windriver.com>]

On 11/23/2017 06:20 PM, Richard Purdie wrote:
> On Mon, 2017-11-20 at 20:22 -0500, Randy MacLeod wrote:
>>> o   Issues with 4.13.10 host kernels booting kvm x86 guests on
>>> Tumbleweed (Suse) and Fedora 26 (attempting to see if 4.13.12
>>> helps)
>>   
>> Robert, can you test Fedora 26. It would help to have a defect open
>> with steps to reproduce or
>> something about the typical workflow/ build time/ day of the week/
>> phase of the moon.
> 
> We have some further data:
> 
> a) The issue occurs on 4.13.12
> 
> rpurdie@tumbleweed:/tmp> cat /proc/version
> Linux version 4.13.12-1-vanilla (geeko@buildhost) (gcc version 7.2.1 20171020 [gcc-7-branch revision 253932] (SUSE Linux)) #1 SMP PREEMPT Wed Nov 8 11:21:09 UTC 2017 (9151c66)
> 
> b) The hang usually occurs at the TIMER line in the kernel logs but can
> occur after booting into userspace around the udevd line, or
> occasionally later in the boot process.
> 
> c) The similarity between this and the ppc bug I worked on make me
> strongly suspect qemu's timers are stopping firing and the guest is
> sitting in the idle loop.
> 
> d) I do now have a way to brute force the hangs at will. The attached
> "runqemu-parallel.py" script runs 50 qemus in parallel. In around 45s I
> had 10 hung on the autobuilder. I can provide more info on using that
> script if its not obvious. It does assume my recent master changes to
> the qemuconf files so we don't need to run bitbake -e to run runqemu.
> 
> This could well be the same kind of locking issue we saw on ppc. I'll
> continue to look into that.
> 
> Hopefully this extra information will put us on a good track to
> resolving it now. It is continuing to break builds and stop patch
> merging.

I modified the script to run on my host (I used qemux86, not qemux86-64,
the later one is still in building) (Up to date Fedora 26, the kernel
is 4.13.13):

$ cat /proc/version
Linux version 4.13.13-200.fc26.x86_64 
(mockbuild@bkernel01.phx2.fedoraproject.org) (gcc version 7.2.1 20170915 (Red 
Hat 7.2.1-2) (GCC)) #1 SMP Wed Nov 15 15:46:36 UTC 2017

But didn't see any hangs after 10 minutes, all the qemus reached login. So maybe
it had been fixed on 4.13.13 ?

// Robert

> 
> Cheers,
> 
> Richard
>