Re: [PATCH net-next v3] netmem: replace __netmem_clear_lsb() with netmem_to_nmdesc()

[Simon Horman <horms@kernel.org>]

On Mon, Sep 29, 2025 at 04:48:40PM +0900, Byungchul Park wrote:
> On Mon, Sep 29, 2025 at 10:46:19AM +0900, Byungchul Park wrote:
> > On Fri, Sep 26, 2025 at 04:18:45PM +0100, Simon Horman wrote:
> > > On Fri, Sep 26, 2025 at 12:54:23PM +0900, Byungchul Park wrote:
> > > > Changes from RFC v2:
> > > >       1. Add a Reviewed-by tag (Thanks to Mina)
> > > >       2. Rebase on main branch as of Sep 22
> > > >
> > > > Changes from RFC:
> > > >       1. Optimize the implementation of netmem_to_nmdesc to use less
> > > >          instructions (feedbacked by Pavel)
> > > >
> > > > --->8---
> > > > >From 01d23fc4b20c369a2ecf29dc92319d55a4e63aa2 Mon Sep 17 00:00:00 2001
> > > > From: Byungchul Park <byungchul@sk.com>
> > > > Date: Tue, 29 Jul 2025 19:34:12 +0900
> > > > Subject: [PATCH net-next v3] netmem: replace __netmem_clear_lsb() with netmem_to_nmdesc()
> > > >
> > > > Now that we have struct netmem_desc, it'd better access the pp fields
> > > > via struct netmem_desc rather than struct net_iov.
> > > >
> > > > Introduce netmem_to_nmdesc() for safely converting netmem_ref to
> > > > netmem_desc regardless of the type underneath e.i. netmem_desc, net_iov.
> > > >
> > > > While at it, remove __netmem_clear_lsb() and make netmem_to_nmdesc()
> > > > used instead.
> > > >
> > > > Suggested-by: Pavel Begunkov <asml.silence@gmail.com>
> > > > Signed-off-by: Byungchul Park <byungchul@sk.com>
> > > > Reviewed-by: Mina Almasry <almasrymina@google.com>
> > > 
> > > Hi Byungchul,
> > > 
> > > Some process issues from my side.
> > > 
> > > 1. The revision information, up to including the '--->8---' line above
> > >    should be below the scissors ('---') below.
> > > 
> > >    This is so that it is available to reviewers, appears in mailing
> > >    list archives, and so on. But is not included in git history.
> > 
> > Ah yes.  Thank you.  Lemme check.
> > 
> > > 2. Starting the patch description with a 'From: ' line is fine.
> > >    But 'Date:" and 'Subject:' lines don't belong there.
> > > 
> > >    Perhaps 1 and 2 are some sort of tooling error?
> > > 
> > > 3. Unfortunately while this patch is targeted at net-next,
> > >    it doesn't apply cleanly there.
> > 
> > I don't understand why.  Now I just rebased on the latest 'main' and it
> > works well.  What should I check else?
> 
> I think 1 and 2 ends in 3.  I will fix it and resend it after the merge
> window.

Great, thanks!