Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753216Ab3ISJgP (ORCPT ); Thu, 19 Sep 2013 05:36:15 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:45805 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751629Ab3ISJgN (ORCPT ); Thu, 19 Sep 2013 05:36:13 -0400 Message-ID: <523AC589.5040006@pengutronix.de> Date: Thu, 19 Sep 2013 11:36:09 +0200 From: Marc Kleine-Budde User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130518 Icedove/17.0.5 MIME-Version: 1.0 To: Andre Naujoks CC: davem@davemloft.net, Wolfgang Grandegger , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net 1/3] slip/slcan: added locking in wakeup function References: <1379093833-4949-1-git-send-email-nautsch2@gmail.com> <1379093833-4949-2-git-send-email-nautsch2@gmail.com> In-Reply-To: <1379093833-4949-2-git-send-email-nautsch2@gmail.com> X-Enigmail-Version: 1.5.2 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VACTNhKFEl9krSAacK6o99Mq1EP5LRWUW" X-SA-Exim-Connect-IP: 2001:6f8:1178:4:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1988 Lines: 58 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --VACTNhKFEl9krSAacK6o99Mq1EP5LRWUW Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 09/13/2013 07:37 PM, Andre Naujoks wrote: > The locking is needed, since the the internal buffer for the CAN frames= is > changed during the wakeup call. This could cause buffer inconsistencies= > under high loads, especially for the outgoing short CAN packet skbuffs.= >=20 > The needed locks led to deadlocks before commit > "5ede52538ee2b2202d9dff5b06c33bfde421e6e4 tty: Remove extra wakeup from= pty > write() path", which removed the direct callback to the wakeup function= from the > tty layer. What does that mean for older kernels? (< 5ede52538ee2b2202d9dff5b06c33bfde421e6e4) > As slcan.c is based on slip.c the issue in the original code is fixed, = too. >=20 > Signed-off-by: Andre Naujoks Acked-by: Marc Kleine-Budde Marc --=20 Pengutronix e.K. | Marc Kleine-Budde | Industrial Linux Solutions | Phone: +49-231-2826-924 | Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | --VACTNhKFEl9krSAacK6o99Mq1EP5LRWUW Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlI6xYkACgkQjTAFq1RaXHP3WQCfb9iLAgL99AkUY46wJgSpmFrL cywAnAgai9lg5kttki3STC3xU5aweDXR =4evM -----END PGP SIGNATURE----- --VACTNhKFEl9krSAacK6o99Mq1EP5LRWUW-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/