Subject: Re: Qemu crashes in -next due to 'of: remove *phandle properties from
 expanded device tree'
To: Frank Rowand <frowand.list@gmail.com>
Cc: Frank Rowand <frank.rowand@sony.com>, linux-kernel@vger.kernel.org,
        Rob Herring <robh@kernel.org>
References: <20170614192638.GA15210@roeck-us.net> <5941AB4E.3070804@gmail.com>
 <20170614223559.GA19172@roeck-us.net> <5941D8C0.1020100@gmail.com>
From: Guenter Roeck <linux@roeck-us.net>
Message-ID: <f994f1ab-64dc-85b6-da4d-9c332d9578a3@roeck-us.net>
Date: Wed, 14 Jun 2017 21:12:35 -0700
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On 06/14/2017 05:45 PM, Frank Rowand wrote:
> On 06/14/17 15:35, Guenter Roeck wrote:
>> On Wed, Jun 14, 2017 at 02:31:58PM -0700, Frank Rowand wrote:
>>> Hi Guenter,
> 
> < snip >
> 
>>> Can you also include the console messages before the "[ cut here ]" line?
>>>
>> http://kerneltests.org/builders
>>
>> Check qemu test results in the 'next' column. ppc and ppc64 show related console
>> messages.
> 
> Thanks for the pointer.  Unfortunately I did not see any additional clues (yet)
> in the full log.
> 
> I tried to compare the failed boot to a good boot, but did not find a console
> log for a good boot.  I started at the qemu-ppc-next builder page:
> 
>    http://kerneltests.org/builders/qemu-ppc64-next
> 
> and looked at recent tests that were successful (like #645).  But the log file
> link from that test does not show the contents of the console for tests that
> pass.  Is there some way to see what the console for a successful test looks
> like?
> 
> -Frank
> 
Good (v4.12-rc4):

...
NR_IRQS:512 nr_irqs:512 16
OF: Checking node /
OF:   node '/' compatible '' type 'open-pic' name '' score 0
OF:   node '/' compatible 'open-pic' type '' name '' score 0
OF: Checking node /pci@e0008000
OF:   node '/pci@e0008000' compatible '' type 'open-pic' name '' score 0
OF:   node '/pci@e0008000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000
OF:   node '/soc@e0000000' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/msi@41600
OF:   node '/soc@e0000000/msi@41600' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/msi@41600' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/global-utilities@e0000
OF:   node '/soc@e0000000/global-utilities@e0000' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/global-utilities@e0000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/serial@4500
OF:   node '/soc@e0000000/serial@4500' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/serial@4500' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/pic@40000
OF:     type match
OF:   node '/soc@e0000000/pic@40000' compatible '' type 'open-pic' name '' score 2
OF:   node '/soc@e0000000/pic@40000' compatible 'open-pic' type '' name '' score 0
mpic: Setting up MPIC " OpenPIC  " version 1.2 at e0040000, max 1 CPUs
mpic: ISU size: 512, shift: 9, mask: 1ff
mpic: Initializing for 512 sources

bad:

NR_IRQS: 512, nr_irqs: 512, preallocated irqs: 16
OF: Checking node /
OF:   node '/' compatible '' type 'open-pic' name '' score 0
OF:   node '/' compatible 'open-pic' type '' name '' score 0
OF: Checking node /pci@e0008000
OF:   node '/pci@e0008000' compatible '' type 'open-pic' name '' score 0
OF:   node '/pci@e0008000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000
OF:   node '/soc@e0000000' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/msi@41600
OF:   node '/soc@e0000000/msi@41600' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/msi@41600' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/global-utilities@e0000
OF:   node '/soc@e0000000/global-utilities@e0000' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/global-utilities@e0000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/serial@4500
OF:   node '/soc@e0000000/serial@4500' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/serial@4500' compatible 'open-pic' type '' name '' score 0
OF: Checking node /soc@e0000000/pic@40000
OF:   node '/soc@e0000000/pic@40000' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/pic@40000' compatible 'open-pic' type '' name '' score 0
OF: Checking node /aliases
OF:   node '/aliases' compatible '' type 'open-pic' name '' score 0
OF:   node '/aliases' compatible 'open-pic' type '' name '' score 0
OF: Checking node /cpus
OF:   node '/cpus' compatible '' type 'open-pic' name '' score 0
OF:   node '/cpus' compatible 'open-pic' type '' name '' score 0
OF: Checking node /cpus/PowerPC,8544@0
OF:   node '/cpus/PowerPC,8544@0' compatible '' type 'open-pic' name '' score 0
OF:   node '/cpus/PowerPC,8544@0' compatible 'open-pic' type '' name '' score 0
OF: Checking node /chosen
OF:   node '/chosen' compatible '' type 'open-pic' name '' score 0
OF:   node '/chosen' compatible 'open-pic' type '' name '' score 0
OF: Checking node /memory
OF:   node '/memory' compatible '' type 'open-pic' name '' score 0
OF:   node '/memory' compatible 'open-pic' type '' name '' score 0
No matching open-pic node
------------[ cut here ]------------
kernel BUG at arch/powerpc/platforms/85xx/corenet_generic.c:50!

So, in __of_device_is_compatible(), the difference is in
__of_device_is_compatible() after

         /* Matching type is better than matching name */

Further debugging shows that device->type is NULL in the bad case.

OF: Checking node /soc@e0000000/pic@40000
OF:     trying type match open-pic - <NULL>
OF:   node '/soc@e0000000/pic@40000' compatible '' type 'open-pic' name '' score 0
OF:   node '/soc@e0000000/pic@40000' compatible 'open-pic' type '' name '' score 0

Do you need more information ?

Thanks,
Guenter