Re: Regression in kernel 4.12-rc1 for Powerpc 32 - bisected to commit 3448890c32c3

[Larry Finger]

On 06/22/2017 09:12 AM, Al Viro wrote:
> On Wed, Jun 21, 2017 at 04:49:46PM -0500, Larry Finger wrote:
> > On 06/21/2017 04:34 PM, Al Viro wrote:
> > > On Wed, Jun 21, 2017 at 04:31:40PM -0500, Larry Finger wrote:
> > > > On 06/21/2017 04:22 PM, Al Viro wrote:
> > > > > How about the .config that works on parent of that commit?
> > > >
> > > > Attached.
> > >
> > > OK... am I right assuming straight jessie/powerpc userland?
> >
> > Actually Mint 12 with noting fancy. The machine mainly exists to test the
> > wireless drivers work on big-endian hardware.
> >
> > 'cat /etc/issue' reports "Debian GNU/Linux 7".
>
> Ugh...  MintPPC appears to be dead.  On KVM with Debian userland (either
> jessie or wheezy - no difference in result) booting the commit in
> question with your .config oopses as soon as pata_macio is initialized,
> due to the bug in "treewide: Move dma_ops from struct dev_archdata into
> struct device", and after cherry-picking your own fix for that (commit
> 46f401c4297a "powerpc/pmac: Fix crash in dma-mapping.h with NULL dma_ops")
> the result boots just fine.
>
> Again, that happens both for Debian 8 and Debian 7 userlands, so unless
> Mint had been doing something very odd there, I would question the accuracy
> of your bisect...

Any chance that real hardware differs from KVM emulation? All I know at this 
point is that commit f2ed8beb with 46f401c4 backported boots OK and commit 
3448890c with the same backport fails.

I will try loading jessie and see what happens.

Thanks for investigating.

Larry