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

From: Al Viro
Date: Thu Jun 22 2017 - 10:12:12 EST


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...