From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: Re: [PATCH rdma-next] Revert "IB/core: Add flow control to the portmapper netlink calls" Date: Wed, 31 May 2017 07:04:37 +0300 Message-ID: <20170531040437.GE5406@mtr-leonro.local> References: <20170529082423.1180-1-leon@kernel.org> <20170530212431.GA21008@ssaleem-MOBL4.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="tVmo9FyGdCe4F4YN" Return-path: Content-Disposition: inline In-Reply-To: <20170530212431.GA21008-GOXS9JX10wfOxmVO0tvppfooFf0ArEBIu+b9c/7xato@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Shiraz Saleem Cc: Doug Ledford , Mustafa Ismail , Faisal Latif , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Leon Romanovsky , Steve Wise List-Id: linux-rdma@vger.kernel.org --tVmo9FyGdCe4F4YN Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, May 30, 2017 at 04:24:31PM -0500, Shiraz Saleem wrote: > On Mon, May 29, 2017 at 11:24:23AM +0300, Leon Romanovsky wrote: > > From: Leon Romanovsky > > > > The commit cea05eadded0 ("IB/core: Add flow control to the portmapper netlink calls") > > changed netlink to be blocked for all RDMA clients. This workaround > > worked perfectly for portmapper, but is not correct for the whole > > NETLINK_RDMA family. > > > > The request/response should always be blocking and asynchronous > > notification should always be non-blocking. > > > > It is library and user-space application to chose how to handle recvmgs, > > as an example see nl_recvmsgs() and nl_socket_set_nonblocking() calls of > > libnl library. > > > > Send timeout is not needed too and can be configured with SO_SNDTIMEO socket > > option. > > > > This reverts commit cea05eadded0d4eb59f7be6e1f1560eb6bfde2bf. > > > > Signed-off-by: Leon Romanovsky > > This commit was accepted with much feedback from you. > > https://patchwork.kernel.org/patch/9235137/ > > Not clear from your description to determine what your trying to fix. > > Simply reverting a commit that solves a real problem is not acceptable. > > Please come up with a solution without breaking portmapper. 1. It was cosmetic comments, I didn't give my reviewed-by tag, so please don't put blame on me, 2. The commit cea05eadde broke NETLINK semantics for whole RDMA. 3. The commit cea05eadde made libnl library (basic block of user-space part of netlink) to work incorrectly and not according to _blocking/_nonblocking semantics. 4. Reverting is a common practice in Linux kernel. Patches are not carved in stones. 5. I proposed a solution -> go and fix your user space program. Thanks > > Shiraz --tVmo9FyGdCe4F4YN Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEkhr/r4Op1/04yqaB5GN7iDZyWKcFAlkuQNUACgkQ5GN7iDZy WKf/wQ/5AUQ87xgD6ov25fYuQzfOgOpxpzK05kDRFJaPNYHuErLE4H9mNlrtTHQY TsmRjr+QGGNnTXjFNr7F9jByeLuI9oYcKTz6uwpTAyxlhp1GjEoCt0qSR7at+suq R6Cg8ZZ/70ElTMdmg4afsDEXlLzPbU5A503xXD5eA3rfDgyV7Eq45j0n8SYbrcf4 M30Fo82sfOtR8TpUZVY7KM37tBoBddF4P+t/ms3dLNoFpm+2+RDT25CcXd65/RZf BlVxDNu/wC4638erpfa6UC9KiA09X1u4enboVJOyktiw+FAugx6Rper2adb6gs0i gMiRHLonO6/6nvaXvSfKqFiNJxCcPkwG34YpIscuzF0t8BFUu5AO4roM+wQ8+Ul1 987r/FT1NSeiR1k/i9Ou3I1EeiEh7qK2TPyPqdlupHzoN8zQFpLwMJ0vu/5DFPqr Bygi3VHbB093Ia3iOpkjN5pHPrkbp/ccaMRzh5trD3QXQKwsAGmzzNg0jDe9et36 rSlU/iW/cqP9DUzc5X/q9rzlMi4G+7V7r94Scr1BLWBj8JqnKEaD9l1jrXiVIwJk YwWCzjnCvkeyYJCjyTjK658je0NcIYvdE8mc6CLq5Rq4KSKt/dkTsQ8+JgkcYmoF i3ZSPPWUnuRRkw6EyR5XjmG4B4yBANoPwX23aAXHxOMtxhHBNwA= =RRHl -----END PGP SIGNATURE----- --tVmo9FyGdCe4F4YN-- -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html