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[23.128.96.18]) by mx.google.com with ESMTP id qc18si2204611ejb.574.2021.03.18.12.11.53; Thu, 18 Mar 2021 12:12:19 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=tgdA7HX1; spf=pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-wireless-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232689AbhCRTLM (ORCPT + 99 others); Thu, 18 Mar 2021 15:11:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231590AbhCRTLB (ORCPT ); Thu, 18 Mar 2021 15:11:01 -0400 Received: from mail-il1-x134.google.com (mail-il1-x134.google.com [IPv6:2607:f8b0:4864:20::134]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A80EAC06174A for ; Thu, 18 Mar 2021 12:11:01 -0700 (PDT) Received: by mail-il1-x134.google.com with SMTP id d2so5892249ilm.10 for ; Thu, 18 Mar 2021 12:11:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=hl/o1czNNh5eByBOw2SNzW+IoLTK83DZiXZSJxM0tiQ=; b=tgdA7HX1OB8coNDG57ztJeSNSTNOPXdyhJEVRUaRg6O4ah3TJqZjg6gfYl89R/o8UG E/ySnIL7fH5xxigZCGthDXYlPYwHEeF0GlLTQUWqGpjR7GIkbhf9f4ZJUHS7q5RD8TX3 HnrO5Tr0wm++4l8QiDI5HAIaNhw99ljY4U3YFHyeGjXHbrRgpYM9J7DBrZxQLzrN28TC ghtD1NRyXzPm09bLSm83KoYmEvdlmLaj3PcLVQTmCOfQC6rEfnc16C9jysMJx1//slKr YYK0Es5YmWa+RFjA630FKrbwwKaRWU1RWTWbtqGEHaUZgjGmxEuXA+Zel7H0WMZsUjFJ 5xoQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=hl/o1czNNh5eByBOw2SNzW+IoLTK83DZiXZSJxM0tiQ=; b=AGnieHShl5omyv/TNWB03nnd1AfpsGJpnZoWehhNIuBBIH0Q8LzJmfxsO6x1KtwsRb F/fGA5oik8wVcZw+IBqz1HcFeLJWHoMcvtCgjC8cnaJkQdwQAGGXN1/LeNXRHI0R7OEM F07wCnSLI/zvtdc8N9DyeSkz+guY+xcCpvBBOfbQmX9EmbTlTGLs+hxnM5yxX4iZjdqm ywAdUbdzoOkv3m/r10UwBDn8yk6gLI4WnTq0liu5OSBwZN1oAT4nhe+FYLbLixMZ75lm fpmSw9gR9wVzClqUnfZfNtOAwRW55IDT95CDtGssOrL44qp5DC3OhapBQeN/dYgbitDr UXEA== X-Gm-Message-State: AOAM532sDgxMcPYpfH43/umWvksQ9yDi/kSrBYv3eYhCxtEn90y2J0aF qyPBtSz6J0qKfJ5fxGCccu5MPpUt91wwZbM3V0GHSd2q6cg= X-Received: by 2002:a05:6e02:1411:: with SMTP id n17mr53238ilo.61.1616094661045; Thu, 18 Mar 2021 12:11:01 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Peter Collingbourne Date: Thu, 18 Mar 2021 12:10:49 -0700 Message-ID: Subject: Re: [PATCH v2] cfg80211: avoid holding the RTNL when calling the driver To: Johannes Berg Cc: linux-wireless@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Thu, Mar 18, 2021 at 12:55 AM Johannes Berg wrote: > > Hi Peter, > > > > I'm seeing warnings like this on 5.12.0-rc2 which I think were caused > > by your patch. > > > > [ 4.898946][ T455] ------------[ cut here ]------------ > > [ 4.899434][ T455] RTNL: assertion failed at net/core/dev.c (10988) > > Yes, sorry about that. I clearly didn't audit that particular code path > (well enough, or at all) with the locking changes. > > Even worse, it probably deadlocks? Yes, it was deadlocking after a few minutes, although at that time I hadn't confirmed that the deadlock was being caused by the patch or by some other issue. > In any case, I fixed it here, I believe: > > https://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211.git/commit/?id=77cbf790e5b482256662e14c8b6ef4fecb07d06d I cherry-picked that patch and tested it on my setup, and it fixed both the warnings and the deadlocks. So if you like you can add my: Tested-by: Peter Collingbourne to that patch. Peter