Re: : Re: [PATCH] libmnl: add MNL_TYPE_UARR for devlink u64 array attributes

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Tue, Jun 23, 2026 at 10:33:50AM +0000, Ratheesh Kannoth wrote:
> From: Pablo Neira Ayuso <pablo@netfilter.org> 
> Subject: [EXTERNAL] Re: [PATCH] libmnl: add MNL_TYPE_UARR for devlink u64 array attributes
> >  include/libmnl/libmnl.h | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/include/libmnl/libmnl.h b/include/libmnl/libmnl.h
> > index 0331da7..078d517 100644
> > --- a/include/libmnl/libmnl.h
> > +++ b/include/libmnl/libmnl.h
> > @@ -133,6 +133,7 @@ enum mnl_attr_data_type {
> >  	MNL_TYPE_NESTED_COMPAT,
> >  	MNL_TYPE_NUL_STRING,
> >  	MNL_TYPE_BINARY,
> > +	MNL_TYPE_UARR = 129,
> 
> Why 129?
> 
> >  	MNL_TYPE_MAX,
> >  };
> 
> I would like to merge https://patchwork.kernel.org/project/netdevbpf/patch/20260615041042.549715-1-rkannoth@marvell.com/
> But this has a hard coded value 129. I believe, I need to use a macro here instead of 129.  
> 
> 
> The value 129 is based on __DEVLINK_VAR_ATTR_TYPE_CUSTOM_BASE = 0x80 (i.e., 128) defined in the kernel, with custom types starting at that offset. The relevant kernel-side definition is:
>   @@ -406,6 +406,7 @@ enum devlink_var_attr_type {
>           DEVLINK_VAR_ATTR_TYPE_BINARY,
>           _DEVLINK_VAR_ATTR_TYPE_CUSTOM_BASE = 0x80,
>           /* Any possible custom types, unrelated to NLA* values go below */
>            DEVLINK_VAR_ATTR_TYPE_U64_ARRAY,
>    };
> So DEVLINK_VAR_ATTR_TYPE_U64_ARRAY resolves to 0x81 = 129.
> Please see the kernel patch for full context:
> https://lore.kernel.org/all/20260609040453.711932-5-rkannoth@marvell.com/
> 
> Once this libmnl patch is merged, I will update the hardcoded 129 to use
> MNL_TYPE_UARR in:
> https://patchwork.kernel.org/project/netdevbpf/patch/20260615041042.549715-1-rkannoth@marvell.com/

This value is only internal for __mnl_attr_validate(), this validates
the attribute type.

I think this is not what you're searching for...