Re: [GIT PULL] VFIO updates for v5.19-rc1

From: Alex Williamson
Date: Wed Jun 01 2022 - 17:31:44 EST


On Wed, 1 Jun 2022 13:57:52 -0700
Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:

> On Wed, Jun 1, 2022 at 10:11 AM Alex Williamson
> <alex.williamson@xxxxxxxxxx> wrote:
> >
> > I'm not sure where git pull-request is getting the diffstat below, the
> > diff of the actual merge of this against mainline looks far less scary.
> > If I've botched something, please let me know.
>
> It's all normal, and due to you having merges in your tree and
> multiple merge bases.
>
> See
>
> Documentation/maintainer/messy-diffstat.rst
>
> for details (yay, Jonathan scrounged together docs so that I don't end
> up having to write a long email explanation any more, and there are
> links to some of my previous explanations on lore).
>
> That also has a suggested remedy, ie just do a temporary merge and use
> the diffstat from that one instead.

Ok, so I should have gone the one step further than I did and replaced
the diffstat from pull-request with the one from my local test merge,
which would have looked like this:

Documentation/driver-api/vfio-mediated-device.rst | 4 +-
drivers/gpu/drm/i915/gvt/gtt.c | 4 +-
drivers/gpu/drm/i915/gvt/gvt.h | 8 +-
drivers/gpu/drm/i915/gvt/kvmgt.c | 115 +---
drivers/net/ethernet/mellanox/mlx5/core/sriov.c | 65 +-
drivers/s390/cio/vfio_ccw_cp.c | 47 +-
drivers/s390/cio/vfio_ccw_cp.h | 4 +-
drivers/s390/cio/vfio_ccw_fsm.c | 3 +-
drivers/s390/cio/vfio_ccw_ops.c | 7 +-
drivers/s390/crypto/vfio_ap_ops.c | 50 +-
drivers/s390/crypto/vfio_ap_private.h | 3 -
drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 16 +-
drivers/vfio/pci/mlx5/cmd.c | 236 +++++--
drivers/vfio/pci/mlx5/cmd.h | 52 +-
drivers/vfio/pci/mlx5/main.c | 136 ++--
drivers/vfio/pci/vfio_pci.c | 6 +-
drivers/vfio/pci/vfio_pci_config.c | 56 +-
drivers/vfio/pci/vfio_pci_core.c | 254 ++++---
drivers/vfio/vfio.c | 781 ++++++++--------------
include/linux/mlx5/driver.h | 12 +
include/linux/vfio.h | 44 +-
include/linux/vfio_pci_core.h | 3 +-
include/uapi/linux/vfio.h | 4 +-
virt/kvm/vfio.c | 329 ++++-----
24 files changed, 1095 insertions(+), 1144 deletions(-)

> But I can also re-create that messy diffstat (and thus verify that
> what you sent me matches what I got) here locally too.
>
> So while the diffstat is messy and not very useful for a "this is what
> changed" angle (because it has a lot of other changes mixed in), even
> that messy diffstat is actually useful for my secondary reason, namely
> as a verification that yes, I got what you were trying to send and
> just didn't document very clearly because of those multiple merge
> bases.
>
> I can (and do) also check the shortlog, since the actual log doesn't
> have any issues with merges, it's only "diff" that needs a single
> well-defined <start,end> tuple.

Thanks, Linus. Replacing the pull-request diffstat didn't feel quite
right, but I'll do that next time I get a crazy listing. Thanks,

Alex