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Date:   Wed, 28 Apr 2021 10:00:44 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-kernel@vger.kernel.org, Qiushi Wu <wu000273@umn.edu>
Subject: Re: [PATCH 037/190] Revert "RDMA/core: Fix several reference count
 leaks."
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On Wed, Apr 28, 2021 at 02:23:40PM +0200, Greg Kroah-Hartman wrote:

> > We've talked about this specifically before:
> > 
> > http://lore.kernel.org/r/20210331170720.GY2710221@ziepe.ca
> > 
> > I still don't understand what you mean by "udev sees it properly", as
> > above, all the tests I thought of look OK.
> 
> Can you query the udev database to see the attribute values?

It appears so unless I misunderstand your ask:

$ udevadm info -a /sys/class/infiniband/ibp0s9
    ATTR{ports/1/cm_rx_duplicates/dreq}=="0"

> As you say, it's uABI for now, so odds are nothing can be changed.  It's
> just no fun for when other subsystems want to do this same thing, they
> point at this code and say "see, they did it!" :)

Are you sure we shouldn't just formally support this? 

What is the exact technical blocker?

Jason