From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EAA49C433DF for ; Wed, 26 Aug 2020 23:17:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A77FB207CD for ; Wed, 26 Aug 2020 23:17:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726371AbgHZXRd (ORCPT ); Wed, 26 Aug 2020 19:17:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726077AbgHZXRc (ORCPT ); Wed, 26 Aug 2020 19:17:32 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2FCAEC061574 for ; Wed, 26 Aug 2020 16:17:32 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id F362612982996; Wed, 26 Aug 2020 16:00:44 -0700 (PDT) Date: Wed, 26 Aug 2020 16:17:30 -0700 (PDT) Message-Id: <20200826.161730.2188402243333115569.davem@davemloft.net> To: kuba@kernel.org Cc: eric.dumazet@gmail.com, michael.chan@broadcom.com, netdev@vger.kernel.org, kernel-team@fb.com Subject: Re: [PATCH net 0/2] net: fix netpoll crash with bnxt From: David Miller In-Reply-To: <20200826194007.1962762-1-kuba@kernel.org> References: <20200826194007.1962762-1-kuba@kernel.org> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Wed, 26 Aug 2020 16:00:45 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jakub Kicinski Date: Wed, 26 Aug 2020 12:40:05 -0700 > Rob run into crashes when using XDP on bnxt. Upon investigation > it turns out that during driver reconfig irq core produces > a warning message when IRQs are requested. This triggers netpoll, > which in turn accesses uninitialized driver state. Same crash can > also be triggered on this platform by changing the number of rings. > > Looks like we have two missing pieces here, netif_napi_add() has > to make sure we start out with netpoll blocked. The driver also > has to be more careful about when napi gets enabled. > > Tested XDP and channel count changes, the warning message no longer > causes a crash. Not sure if the memory barriers added in patch 1 > are necessary, but it seems we should have them. Series applied and queued up for -stable, thanks Jakub.