Re: [Merge tag 'pci-v4.12-changes' of git] 857f864014: BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8

From: Logan Gunthorpe
Date: Wed Jun 14 2017 - 01:56:12 EST




On 13/06/17 11:00 PM, Greg Kroah-Hartman wrote:
> No, don't modify any drivers, do this in the core chardev code.

Ok, well then maybe I misunderstood what you originally asked for
because I don't see how you can change a fixed allocation to a dynamic
one without touching the driver code which needs to know the major that
was assigned in the end.

> At quick glance, looks good to me, care to clean it up and make it behind
> a config option?

Sure. However, is a config option really necessary here? As is, the
extended dynamic region will only be used if there are too many chardev
majors and it shouldn't have _any_ effect on users that have a small
number. So it seems like not selecting that option is just telling the
kernel to be broken for no obvious trade-off.

Logan