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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B127BC433EF for ; Mon, 18 Jul 2022 11:22:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233516AbiGRLW3 (ORCPT ); Mon, 18 Jul 2022 07:22:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230401AbiGRLW1 (ORCPT ); Mon, 18 Jul 2022 07:22:27 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6924420F52; Mon, 18 Jul 2022 04:22:27 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 00BD861263; Mon, 18 Jul 2022 11:22:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19019C341C0; Mon, 18 Jul 2022 11:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1658143346; bh=zl4uhvMK5ijsxafPJV04weeiNkBSHJF1ueGmZqItmD0=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=g4fk/CMOK9uwjh1k/yKO3I2gpV8VM5/+1IMXQS3SZvRm0yo1G20+oAQ6R1SUNJ1Q+ PGD6uSTVB7xTUB4UFyFxaLqKmMZmamTrMBBsmyxAo6UL9XYCSo7hJCJYgUsqS4+35f Vd6H2i+wmCiXv8rkVpYl0n6jMZPOGEqJRHIL1X9fqONn8CbCB8T1nkhuYJoFEkp6K+ Dfpn7khEfvgJ5Sk56eXT78vtohw/1PXnhv3b1REcF2bsuy654Gv4U6oRRJx2/DWvbG LyY25KOqgSLYmhUiDHVcguNL1i4djJR3KvlJ/CL82nzgJWl+QVwK2QbABp5FdsmNJi +PpNo0o0CAdXA== Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 54B9E4D9EC5; Mon, 18 Jul 2022 13:22:22 +0200 (CEST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Tetsuo Handa , Johannes Berg , Felix Fietkau Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH v2] wifi: mac80211: do not abuse fq.lock in ieee80211_do_stop() In-Reply-To: <9cc9b81d-75a3-3925-b612-9d0ad3cab82b@I-love.SAKURA.ne.jp> References: <00000000000040bd4905e3c2c237@google.com> <81f3eeda-0888-2869-659e-dc38c0a9debf@I-love.SAKURA.ne.jp> <9cc9b81d-75a3-3925-b612-9d0ad3cab82b@I-love.SAKURA.ne.jp> X-Clacks-Overhead: GNU Terry Pratchett Date: Mon, 18 Jul 2022 13:22:22 +0200 Message-ID: <874jzemzrl.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Tetsuo Handa writes: > lockdep complains use of uninitialized spinlock at ieee80211_do_stop() [1= ], > for commit f856373e2f31ffd3 ("wifi: mac80211: do not wake queues on a vif > that is being stopped") guards clear_bit() using fq.lock even before > fq_init() from ieee80211_txq_setup_flows() initializes this spinlock. > > According to discussion [2], Toke was not happy with expanding usage of > fq.lock. Since __ieee80211_wake_txqs() is called under RCU read lock, we > can instead use synchronize_rcu() for flushing ieee80211_wake_txqs(). Ah, that's a neat solution! :) Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen