Re: [PATCH 02/18] block: open code kobj_map into in block/genhd.c

[Greg Kroah-Hartman]

On Fri, Oct 30, 2020 at 11:49:11AM +0100, Geert Uytterhoeven wrote:
> Hi Greg,
> 
> On Fri, Oct 30, 2020 at 11:40 AM Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > On Thu, Oct 29, 2020 at 08:32:42PM +0100, Christoph Hellwig wrote:
> > > On Thu, Oct 29, 2020 at 08:22:36PM +0100, Greg Kroah-Hartman wrote:
> > > > After this, you want me to get rid of kobj_map, right?  Or you don't
> > > > care as block doesn't use it anymore?  :)
> > >
> > > I have a patch to kill it, but it causes odd regressions with the
> > > tpm driver according to the kernel test.  As I have grand plans that
> > > build on the block ѕide of this series for 5.11, I plan to defer the
> > > chardev side and address it for 5.12.
> >
> > Ok, sounds good.
> >
> > Wow, I just looked at the tpm code, and it is, um, "interesting" in how
> > it thinks device lifespans work.  Nothing like having 4 different
> > structures with different lifespans embedded within a single structure.
> > Good thing that no one can dynamically remove a TPM device during
> > "normal" operation.
> 
> /sys/.../unbind?

I said "normal" operations :)

Anyone who uses unbind and is suprised when things go "boom" is naive.

thanks,

greg k-h