From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D4F84DF76; Mon, 14 Jul 2025 23:35:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752536107; cv=none; b=GouMfx3Qjsse5XAYq9SmM5DbUqnUlJ7x5RZsfFIPAK2uk3BuqDeEs8QLOwimbRACEcEYCjrr4v5Sa3dA+4z7/NOWPlYKzzknkCkl/41yV0vM9hAi9ZqUUmhh2PQtPVvYcL1NoOufg8ffQuL9QV4c2oBjXJxoOhrNk2WIdgr3OaY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752536107; c=relaxed/simple; bh=tndqYKv5PsHCA6xhpRVxrUkq6dpnqkPjmvdWrg3TSTA=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=OrOvkwEQTxR9cqxXtthfPXFMRM7EarMmW98ohC05RN8LSKMrX+5fSFvC/RPC/0ax9kNTt3ylajclgqhwBa5TvWtpaqQcFCc44zdUwCIdptKq62HeYz/yf/OQQbaSM6zzHTLxo7mO79z3zT3a8WNgiA7luHD4AOe/ZxqkTDV2Hw0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dPLAFFyl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dPLAFFyl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBED2C4CEED; Mon, 14 Jul 2025 23:35:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752536106; bh=tndqYKv5PsHCA6xhpRVxrUkq6dpnqkPjmvdWrg3TSTA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=dPLAFFylvSdb1xbE2nsGzNaQW3ptcx44wtwElfUX+VxxlH8E9VOmUp1y3sFRgaNd0 UjyPpl3VVLwZyuW6y98qKDcUc0KHtsHzwHTvRYXcbiF0Hq11wqNZ8rgros/EWqzeZC u+jPJK7luDlke1/bRa6mzewl0diih719NdYVVaJdiJXTYuUOA2fSUGEcspd0c3YeLn tT5JE1Ku45nyrUYQ3awurkhlDjhejbfljr0yD3bDhOmAGiK9aq7cAba5ktzEJFwKRv 7Y3SYnV4UXDSNh23YSnARDVWPpDjaLm3SObB8gw9kDRLyRzCq5LJp9vPnF+5JKi0qS u1NPsZ5K4HbHQ== Date: Mon, 14 Jul 2025 16:35:05 -0700 From: Jakub Kicinski To: John Ernberg Cc: Oliver Neukum , Andrew Lunn , "David S . Miller" , Eric Dumazet , Paolo Abeni , Ming Lei , "netdev@vger.kernel.org" , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: Re: [PATCH] net: usbnet: Avoid potential RCU stall on LINK_CHANGE event Message-ID: <20250714163505.44876e62@kernel.org> In-Reply-To: <20250710085028.1070922-1-john.ernberg@actia.se> References: <20250710085028.1070922-1-john.ernberg@actia.se> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 10 Jul 2025 08:50:40 +0000 John Ernberg wrote: > Having a Gemalto Cinterion PLS83-W modem attached to USB and activating the > cellular data link would sometimes yield the following RCU stall, leading > to a system freeze: Do you know which sub-driver it's using? I'm worried that this is still racy. Since usbnet_bh checks if carrier is ok and __handle_link_change() checks the opposite something must be out of sync if both run. Most likely something restored the carrier while we're still handling the previous carrier loss. -- pw-bot: cr