Re: regression: 9a56493f6942 "uts: Use generic ns_common::count" broke makedumpfile 1.6.7

[Mike Galbraith]

On Wed, 2020-12-16 at 18:20 +0300, Kirill Tkhai wrote:
>
> We may consider a patch like the below till updated makedumpfile is not published:

It's nice to be considerate to the tool folks, but that can leave a
wake of cruft (thinks printk ringbuffer.. ew), so it's probably best to
just let it break.  The why and wherefore is documented in this thread,
that's enough for anybody who needs a quick fix to get on with frobbing
their dang buggy bleeding edge kernel ;-)

> diff --git a/include/linux/utsname.h b/include/linux/utsname.h
> index 2b1737c9b244..d6bcad448f52 100644
> --- a/include/linux/utsname.h
> +++ b/include/linux/utsname.h
> @@ -8,6 +8,7 @@
>  #include <linux/ns_common.h>
>  #include <linux/err.h>
>  #include <uapi/linux/utsname.h>
> +#include <linux/kref.h>
>
>  enum uts_proc {
>  	UTS_PROC_OSTYPE,
> @@ -21,6 +22,7 @@ struct user_namespace;
>  extern struct user_namespace init_user_ns;
>
>  struct uts_namespace {
> +	struct kref unused;
>  	struct new_utsname name;
>  	struct user_namespace *user_ns;
>  	struct ucounts *ucounts;