Commit 8ae030c34 breaks USB on the Raspberry Pi 4

[Michael Stapelberg]

On Wed, 15 Sept 2021 at 10:54, nicolas saenz julienne <nsaenz at kernel.org> wrote:
>
> On Wed, 2021-09-15 at 09:55 +0200, Michael Stapelberg wrote:
> > Hey Nicolas
> >
> > On Wed, 15 Sept 2021 at 09:42, nicolas saenz julienne <nsaenz at kernel.org> wrote:
> > >
> > > Hi Michael,
> > >
> > > On Wed, 2021-09-15 at 08:33 +0200, Michael Stapelberg wrote:
> > > > Thanks for your mail.
> > > >
> > > > My system does not use any Linux kernel modules (=m), all required
> > > > code is compiled into the kernel itself (=y).
> > > > The root file system does not contain any .ko files.
> > >
> > > Are you building your own kernels? Then I suggest to configure the
> > > raspberrypi-reset driver as builtin (=y) so it's available in your kernel
> > > image.
> >
> > Yes, I have already done that. I was more interested in fixing this
> > problem for others, and/or avoiding similar problems in the future.
> >
> > >
> > > Could you provide more information on how your system/rootfs is built and
> > > setup?
> >
> > Please see https://gokrazy.org/, specifically https://gokrazy.org/quickstart/.
> > The source for the gokr-packer tool is at
> > https://github.com/gokrazy/tools/tree/master/cmd/gokr-packer
> >
> > In summary, my tool builds a read-only SquashFS root file system that
> > directly starts processes written in Go.
> > The boot partition (FAT32 for the Raspberry Pi) contains only the
> > Linux kernel and Raspberry Pi firmware files.
>
> Thanks for the info.
>
> IMO the solution is to maintain your own configuration. The decision not to use
> kernel modules, even if reasonable given the scope of gokrazy, is a big
> deviation from how the kernel is regularly consumed. The majority of the arm64
> defconfig users need the kernel image to be as small as possible to avoid
> bloating the boot partition, and allowing for reasonable boot speeds (imagine
> having to load a 1GB kernel image from the SD card).

Yep, effectively I am maintaining my own configuration, but I still
run defconfig before applying my own additions to .config.

I think that in general I do want the changes that defconfig brings,
so defconfig+additions is the only way I see, and I thought this was
best practice?

Are you saying there might be a better option? Or perhaps the best
move is to just support modules in gokrazy after all.

Thanks for your advice,

>
> Regards,
> Nicolas
>