Re: Regression on next-20170203 spi/for-next 3f87493930a0f qemu on x86_64

[Stephen Rothwell]

Hi all,

On Sun, 5 Feb 2017 10:17:29 +1100 Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
>
> On Sat, 4 Feb 2017 12:05:42 -0800 "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx> wrote:
> >
> > though so it seems something with my configuration and boot. I
> > bisected next-20170203 between its latest commit and v4.10-rc6 and
> > ended up with this bad commit:
> > 
> > 104a519fe1732b4e503ebc7b4ac71b6f0b8a0b62
> > 
> > $ git show 104a519fe1732b4e503ebc7b4ac71b6f0b8a0b62
> > commit 104a519fe1732b4e503ebc7b4ac71b6f0b8a0b62
> > Merge: 7c3b1edeee66 3f87493930a0
> > Author: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> > Date:   Fri Feb 3 12:30:38 2017 +1100
> > 
> >     Merge remote-tracking branch 'spi/for-next'
> > 
> > I have checked Next/SHA1s and it shows:
> > 
> > mcgrof@piggy ~/linux-next (git::original)$ grep spi Next/SHA1s
> > spi-nor        dc12bcccadafb5441170e6b7c8a438c91d4f385b
> > spi        3f87493930a0f934549b04e100ecc2110e4f1efd
> > hwspinlock    bd5717a4632cdecafe82d03de7dcb3b1876e2828
> > 
> > The commit 3f87493930a0f934549b04e100ecc2110e4f1efd then seems to be
> > what I need to test. I have cloned Mark's spi tree and just tried to
> > boot the for-next branch (on v4.10-rc1) on
> > 3f87493930a0f934549b04e100ecc2110e4f1efd, and it boots successfully.
> > This would lead me to believe this issue might be related to the merge
> > conflict resolution done by Stephen, but wanted to check and ask.
> > Perhaps there might be some specific tests I can run.  
> 
> OK, it is possible that the merge is actually incorrect.  I did *not*
> do any manual resolution of that merge and git only reported an
> automatic resolution in file drivers/spi/spi-bcm-qspi.c (which looks ok
> from a quick glance).
> 
> It is always possible that there is some semantic conflict that git
> won't see and didn;t also involve a syntactic conflict or a build
> failure.  e.g. the internal semantics of a function changes on one side
> of the merge but a new usage expecting the old semantics is introduced
> on the other side.

Just to mention, there was no change to the spi tree between
next-20170202 and next-20170203.  I assume that next-20170202 is fine?
If so, you could try bisecting with next-20170202 as good and
104a519fe1732b4e503ebc7b4ac71b6f0b8a0b62 as bad.  I have no idea if
that sort of bisec will even work, though.

Or if commit 8cfb3801a57a (the merge of the spi tree in next-20170202)
is fine, then you could try using that as your starting good (that will
remove a lot of next-20170202).

-- 
Cheers,
Stephen Rothwell