Re: [PATCH v18 11/15] IB/mlx4: untag user pointers in mlx4_get_umem_mr

From: Jason Gunthorpe <jgg@ziepe.ca>
To: Andrey Konovalov <andreyknvl@google.com>
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	Catalin Marinas <catalin.marinas@arm.com>
Subject: Re: [PATCH v18 11/15] IB/mlx4: untag user pointers in mlx4_get_umem_mr
Date: Wed, 17 Jul 2019 08:58:28 -0300	[thread overview]
Message-ID: <20190717115828.GE12119@ziepe.ca> (raw)
In-Reply-To: <CAAeHK+xPPQ9QjAksbfWG-Zmnawt-cdw9eO_6GVxjEYcaDGvaRA@mail.gmail.com>

On Wed, Jul 17, 2019 at 01:44:07PM +0200, Andrey Konovalov wrote:
> On Tue, Jul 16, 2019 at 2:06 PM Jason Gunthorpe <jgg@ziepe.ca> wrote:
> >
> > On Tue, Jul 16, 2019 at 12:42:07PM +0200, Andrey Konovalov wrote:
> > > On Mon, Jul 15, 2019 at 8:05 PM Jason Gunthorpe <jgg@ziepe.ca> wrote:
> > > >
> > > > On Mon, Jul 15, 2019 at 06:01:29PM +0200, Andrey Konovalov wrote:
> > > > > On Mon, Jun 24, 2019 at 7:40 PM Catalin Marinas <catalin.marinas@arm.com> wrote:
> > > > > >
> > > > > > On Mon, Jun 24, 2019 at 04:32:56PM +0200, Andrey Konovalov wrote:
> > > > > > > This patch is a part of a series that extends kernel ABI to allow to pass
> > > > > > > tagged user pointers (with the top byte set to something else other than
> > > > > > > 0x00) as syscall arguments.
> > > > > > >
> > > > > > > mlx4_get_umem_mr() uses provided user pointers for vma lookups, which can
> > > > > > > only by done with untagged pointers.
> > > > > > >
> > > > > > > Untag user pointers in this function.
> > > > > > >
> > > > > > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
> > > > > > >  drivers/infiniband/hw/mlx4/mr.c | 7 ++++---
> > > > > > >  1 file changed, 4 insertions(+), 3 deletions(-)
> > > > > >
> > > > > > Acked-by: Catalin Marinas <catalin.marinas@arm.com>
> > > > > >
> > > > > > This patch also needs an ack from the infiniband maintainers (Jason).
> > > > >
> > > > > Hi Jason,
> > > > >
> > > > > Could you take a look and give your acked-by?
> > > >
> > > > Oh, I think I did this a long time ago. Still looks OK.
> > >
> > > Hm, maybe that was we who lost it. Thanks!
> > >
> > > > You will send it?
> > >
> > > I will resend the patchset once the merge window is closed, if that's
> > > what you mean.
> >
> > No.. I mean who send it to Linus's tree? ie do you want me to take
> > this patch into rdma?
> 
> I think the plan was to merge the whole series through the mm tree.
> But I don't mind if you want to take this patch into your tree. It's
> just that this patch doesn't make much sense without the rest of the
> series.

Generally I prefer if subsystem changes stay in subsystem trees. If
the patch is good standalone, and the untag API has already been
merged, this is a better strategy.

Jason