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 1629856B7B for ; Thu, 2 May 2024 10:54:42 +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=1714647283; cv=none; b=qKc2B4iM79FqMdWQXQ9u6O4aPRmHYLu0jFllpOynLSp6qQ2L+y4M/M17ZZCExJ37lVQTRt9RcRKZI+QTKPYWQMelAIz1soaR8Ocflj1bVcTnjKfeTjSUvAgrKFErLkw01dzICuoofhS/HTiMyBc475MurMZZRBg0Pf6R39BEsTQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714647283; c=relaxed/simple; bh=mFjq/ifnBqNev0YMd3Y/GcESWFORD7xvByocsgi28E0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=aJ60JUpQwMO8+h3Ou+XVsiIfAZajRStYUxx87fCX3RoOtQo7L7Ww2QNVzOeFgsJaKjoXkr0LTMh4pFr4e6HY39xX5XBo2cAcagoD2cFS1fVCPbvPBykGHdJCh/wxt7vmPlk+mPx/HwodGHIOngxT7FFoOHn55F7QuW9wy4nXLIU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=kmTmrvzQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="kmTmrvzQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F290AC113CC; Thu, 2 May 2024 10:54:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1714647282; bh=mFjq/ifnBqNev0YMd3Y/GcESWFORD7xvByocsgi28E0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=kmTmrvzQYlfAVUFd39La/CXCZ17PNX78JUC/6KcrYUG+TYK4OSSU9nmalBFTwckiM 0xxRBOj/yyttL3/l4+Cf1sZdHAeAx2p88bUhfVVhXgH3iWKSfBYFSDrJZWyGmHitvP b7EVW6SwtmaIC6hhLS3MbLWPIdpv63n85iPdRMf8= Date: Thu, 2 May 2024 12:54:39 +0200 From: Greg Kroah-Hartman To: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= Cc: Johan Hovold , linux-usb@vger.kernel.org Subject: Re: [PATCH] USB: serial: use tty_port_register_device_serdev Message-ID: <2024050204-recreate-exerciser-bd62@gregkh> References: <20240502100728.7914-1-mans@mansr.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Thu, May 02, 2024 at 11:45:44AM +0100, Måns Rullgård wrote: > Johan Hovold writes: > > > On Thu, May 02, 2024 at 11:07:28AM +0100, Mans Rullgard wrote: > >> Use tty_port_register_device_serdev() so that usb-serial devices > >> can be used as serdev controllers. > > > > I'm afraid it's not that easy. The reason serdev is not enabled for > > usb-serial is that there's currently no support for handling hotplug in > > serdev. The device can go away from under you at any time and then you'd > > crash the kernel. > > Oh, that's unfortunate. Regular serial ports can go away too, though, > and that seems to be handled fine. What am I missing? How is it handled? Normal serial ports can go away but in practice, it's a rare occurance, and usually people use serdev for devices where the ports can not be removed (i.e. internal connections). thanks, greg k-h