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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 94E00C433DF for ; Mon, 17 Aug 2020 13:42:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6FAC020789 for ; Mon, 17 Aug 2020 13:42:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="LPV8zIH7"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="XrcVTgUc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728752AbgHQNmM (ORCPT ); Mon, 17 Aug 2020 09:42:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728687AbgHQNlp (ORCPT ); Mon, 17 Aug 2020 09:41:45 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 786BDC061359; Mon, 17 Aug 2020 06:41:15 -0700 (PDT) Date: Mon, 17 Aug 2020 15:41:09 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1597671670; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z3bPb+Be6pafKwEQBFvSpZWJceorkqDy/T/jpI/cYYc=; b=LPV8zIH7ojDEvlwh4FItD/FhOn+ITBTQl8BS00MO2pmoWjvhq0HeIXJD27igEfDhRA0gU6 tYcJYLc2S8tKvAVPJORsH7FCdoIKK735/G7ZDMgTbfYRtJpMKVLwkixVv8lqd8eBEzRrRU UfG6ZB1eq1rBUQQrblKC/sCNWWKTfwPAaiI7omBgFKdZmasVVqLdRT/3c+m7snLtBKwZeA UoaMbgwUSqZt471hfrY+uS0si9kdSqcZAEYT27PM7VxBWuBP0k/58R+7LgL3Zjz1IHB0Hi mRWYiGeixmjgNN8uNvGDpFdsqWBeHiu6PZ/BqhM3QZN7GyBJg68zvw5OC7KxmQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1597671670; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z3bPb+Be6pafKwEQBFvSpZWJceorkqDy/T/jpI/cYYc=; b=XrcVTgUcnRvwNtPs8ZqOYuE3QRHNg1fW3dkB11UwWhMm4+8DFZKdQW6KcfCyYVlilzupQq MtOkhNpeHlmJyHAw== From: Sebastian Andrzej Siewior To: Steven Rostedt Cc: LKML , linux-rt-users , Thomas Gleixner , Carsten Emde , John Kacur , Daniel Wagner , Tom Zanussi , "Srivatsa S. Bhat" Subject: Re: Question on 5.4.55 merge into 5.4-rt Message-ID: <20200817134109.hu73gjafbdb2n3rz@linutronix.de> References: <20200814185421.74b1ddc8@oasis.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20200814185421.74b1ddc8@oasis.local.home> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-08-14 18:54:21 [-0400], Steven Rostedt wrote: >=20 > When merging 5.4.55 into 5.4-rt I hit the following conflict: =E2=80=A6 >=20 > Where we are doing something slightly different. Placing the skb on the > sd->tofree_queue and raising NET_RX_SOFTIQ instead. >=20 > Now that the vanilla stable 5.4 kernel doesn't call kfree_skb() from > irqs_disabled, can I safely revert this entire change? Not if you mean dropping skbufhead-raw-lock.patch. We can drop `tofree_queue' and everything related to it. We need to keep the `raw_lock' and the `rps_lock()' hunks for `sd->input_pkt_queue'. The other queue, `sd->process_queue', is protected by local_bh_disable() so these hunks can be dropped in the more recent RT versions with the re-written softirq code (v5.0.19-rt10+). > Is it safe to call kfree_skb() from local_bh_disable()? of course it is. > I'm assuming it is, but just want to clarify. I'll be continuing > merging latest stable (with this revert), but please yell if you think > it will break? > > Thanks! >=20 > -- Steve Sebastian