From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=74.125.227.129 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793961909; b=UoLxNMrj9t/N0SwFEupZR230LPGj/Q0wAQlbdMtpCA32mxa1nb8o2X25e/8xTQZ07bWI mfEP10fdYLeZC2Ware2kbe37He/Q8tYxeRi8/aAy6La76p7D39yCnh5ylxD2ddIvG52fq S29ecVP8uX/IDioBCBbiKyLXTVtm0MWwcw7rwIkYZziad5MJQxsT0qpDk13aFZaBqi9Kn 52Z7PyUZkP44HV/UWnzKdLsDygdSUO2nb569JZloV2G7B5mWXy9Xq1s0IdJGcDhLVU1qc cQtKwoqIn2BLXwhNKfF6GDWs7z7ON0SMi9fPEPwA1C4y1/LZRN9L7QI9JT7thNLnpiQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793961909; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: Message-ID:Date:MIME-Version:User-Agent:Subject:To:Cc:References: Content-Language:From:In-Reply-To:Content-Type: Content-Transfer-Encoding; bh=mK5Jdfitjwy2qBnVXmB5t+/eIsoKS4R4I1jh8e8KWtg=; b=z29cggOXMUbE5E97P1nWTPkVLLijVY8/+MBKZS4ImkTxESXPvj/Gf8Eq7IF43Z9X6Jvz bCyy+bP9w9yyi87UL4I83/w4hx/KnrLrmt80XZum1auXrmdTW/Jl0hJYIqW8HBcoqnyfp 3mOwRFLJ039l1zoqZAnLgX/16PZfcyVMnoM8qu06jySxjqXWuIFOnL/Gc0IPT8SaeKCF/ esZ6Bp8MBbxNWeyIV85EhsTZ3L0yQ8vdgXdPy0o294tv7ygG8MLecRv/ZGVO2LqPsiWo1 iUlB8nv/wOVsrfTRcJ1s/NA9Y55u3euwRmi6ILQzGU9BEO67xmhcENjAH1mk3kKph8w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=IFP2w+V4; arc=none smtp.remote-ip=74.125.227.129 Received: from mail-pj2-f1.google.com (mail-pj2-f1.google.com [74.125.227.129]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76AD7606A32E for ; Fri, 6 Nov 2026 10:45:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 76AD7606A32E Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=IFP2w+V4 Received: by mail-pj2-f1.google.com with SMTP id d9443c01a7336-2ed408b0d0bso3264375ad.0 for ; Fri, 06 Nov 2026 02:45:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1793961909; x=1794566709; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=mK5Jdfitjwy2qBnVXmB5t+/eIsoKS4R4I1jh8e8KWtg=; b=IFP2w+V4jns0t4yYEy5GFCJrNcp9y71ad7pD++ZnOBHlKQctT+UyUxQcBDU8YViV9j X4tmcb9ziENv/Bh7ir1qwdPfx9lTPXVZuB80HluQdBaN1r6aUl/6w4yYW5XjHJ9rw39y ZRtowgsbzWkN9mCY6/oSPlcbeOQU0AHomUMjfv2CiGDrDjRPqoNTdI8FaYoLTYdFP2Ak pzJAb/tt1X8tiZPYDImwjmPM8LkuYnshYIk8EgHCP/brvCh88/KWcua0BvQfMUeVsvjE MtXSiqoew+qkr9lx3NZ/laHEBoEW7mzhGQXLEPzy+D2GXEERDkhEcjQxUoJilQsctZex rlsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1793961909; x=1794566709; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=mK5Jdfitjwy2qBnVXmB5t+/eIsoKS4R4I1jh8e8KWtg=; b=1dQ0eh5Zeq7ObGpVKpwSbWO62l7ZYHfoz3DAEkNfPbiMVargJIRr+p33VR82G8qF/K 2UZB4Qi3D9X4W8JpoSOw5gOXdXZNeWFE7QnUUu0bFJ6xwDS2WGv0QGccM3MgP4XY/T2h ZpVmFpn5qfVHrymVXAMKtO0Xq7hUTNk1Eczk7bMfe4CogfgTynQam3ZP4QCOtIZxHfED 1hLOpBo4cLGadq/rYugKqITlItds5YkpJZEjaV4tTjauUmmu5TJDQk9s8TsPP9CKNL50 Ufp8pqu6YRyrD42VlasTLnyxWdjSJNWPxcHixDjmVHnw+sscpW4EgjCnhAQAGjpSjhm0 BoRQ== X-Forwarded-Encrypted: i=1; AL+hErEgwkxhdqO5QlmNNGRh8ksWOY9ilOghLLTvvz6HHXeRTIQJkO3BaRrZKdtJScZV4pJAngbvtHHgQwU7EDE=@vger.kernel.org X-Gm-Message-State: APuU4Z//OozgN1FjFcWc31jAPLvwCPgjKsk2rKpuX/l9qbps+DXNzyGx aNcnvfjmGAbLPj8gn+rERV9DmAB1ESDA0JR/PN1rJdgz73nzluh1G6c2 X-Gm-Gg: AYBFou1hCFO+wBqBUfqSdF/9SHPLVSgnGqKjboSSEe6L3R5Uu9FFbZPPq8ESg4ABMND JjSbUfa9qpLOMzwg7Vtyv0IVWXG/3fPZSAWD4rEdXgHhg2rkLgHmsoYCx6xgmMuKRjjaFoR9c1F G+xZyqUpBR40DL/5HawNLfE/2jtVxe//GPWKVgdflnk9vrjOmKEdC2/lERjIKftnFIrTizmn0G9 dSchDpuddwpCszxZYt7sZwzhBUIMaeetm7TiE0ykPv1LrnY/4c3eGCspQoAnFmZNRGW3EeJosWg wzHY9BFHV39eEsAlmlpsVi441PtebsP7gl4v7opdeusodwaQpM8Z9BmzA/FO4bagWDFvDuO/yXq 0KRxd9qQm1usrhopeCXD32huh2X6/2NuvGnuL1jCr//Jf6XVs0lzd0fEerIZzDmEvPrzJ3t9GU5 GqHfcSbUpzrIwr4OnZaRJs/SGXrLoKvfAE4LK9LwpK9BLniUpXrZqALzoj0Pe8VkhOCJFUO8Z/U rLuCwknzieCu+TL+l9MGRcguwuxGpQOLkHGS4E/OT9aZcqmZMBHHFB5CfyxCHKTtE9ttI9HFxq2 SEO5EAKOQyIz+gRHlfk9vEySO0Nv/w55pYxljfDST1oyGnb0hbCQg6c/3fM= X-Received: by 2002:a17:902:da87:b0:2ed:205e:eabc with SMTP id d9443c01a7336-2ed41bbd3d4mr26889285ad.32.1793961908564; Fri, 06 Nov 2026 02:45:08 -0800 (PST) Received: from [192.168.100.182] ([110.93.227.81]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2ed47d8915esm4095755ad.67.2026.11.06.02.44.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 06 Nov 2026 02:45:06 -0800 (PST) Message-ID: Date: Fri, 6 Nov 2026 15:44:50 +0500 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net] net: spacemit: Hold RTNL lock in emac_resume() and emac_suspend() To: Troy Mitchell Cc: Vadim Fedorenko , netdev@vger.kernel.org, Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Yixun Lan , Vivian Wang , Chukun Pan , Siddharth Vadapalli , Tomas Hlavacek , Muhammad Bilal , Maxime Chevallier , linux-riscv@lists.infradead.org, spacemit@lists.linux.dev, linux-kernel@vger.kernel.org References: <20261105123441.2524171-1-alitariq45892@gmail.com> Content-Language: en-US From: Ali Tariq In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 11/6/26 2:43 PM, Troy Mitchell wrote: > On Thu, 5 Nov 2026 17:34:37 +0500, Ali Tariq wrote: >> @@ -2056,7 +2059,9 @@ static int emac_suspend(struct device *dev) >> return 0; >> } >> >> + rtnl_lock(); >> emac_stop(ndev); >> + rtnl_unlock(); >> >> clk_disable_unprepare(priv->bus_clk); >> netif_device_detach(ndev); > This can deadlock. emac_stop() -> emac_down() calls > cancel_work_sync(&priv->tx_timeout_task) with RTNL now held, while > emac_tx_timeout_task() starts with rtnl_lock(). > Thanks Troy, that makes sense. For the deadlock, I think the correct function to call is rtnl_trylock() inside the emac_tx_timeout_task(), which would return if the lock is already held and will hold the lock if it is not. What are your thoughts on this? Does a v2 changing rtnl_lock() to rtnl_trylock() inside emac_tx_timeout_task() make sense? Regards, Ali