Re: [PATCH net-next v5 2/5] ethtool: netlink: add ETHTOOL_MSG_MSE_GET and wire up PHY MSE access

[Oleksij Rempel]

On Mon, Sep 15, 2025 at 08:07:20AM -0700, Jakub Kicinski wrote:
> On Mon, 15 Sep 2025 11:30:52 +0200 Oleksij Rempel wrote:
> > On Fri, Sep 12, 2025 at 05:00:53PM -0700, Jakub Kicinski wrote:
> > > On Fri, 12 Sep 2025 12:07:42 +0200 Oleksij Rempel wrote:  
> > > > I would prefer to keep u64 for refresh-rate-ps and num-symbols.
> > > > 
> > > > My reasoning comes from comparing the design decisions of today's industrial
> > > > hardware to the projected needs of upcoming standards like 800 Gbit/s. This
> > > > analysis shows that future PHYs will require values that exceed the limits of a
> > > > u32.  
> > > 
> > > but u64 may or may not also have some alignment expectations, which uint
> > > explicitly excludes  
> > 
> > just to confirm - if we declare an attribute as type: uint in the YAML
> > spec, the kernel side can still use nla_put_u64() to send a 64-bit
> > value, correct? My understanding is that uint is a flexible integer
> > type, so userspace decoders will accept both 4-byte and 8-byte encodings
> > transparently.
> 
> Theoretically, and yes. But why would you use put_u64 and not
> put_uint() ?

rater.. rater.. rater.. (sound of rusty gears slowly moving)

Right, I was thinking of uint as u32. But in NLA, NLA_UINT is handled
like NLA_U64, so the max is U64_MAX. That clears it up, thanks!

Best Regards,
Oleksij
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