From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-182.mta0.migadu.com (out-182.mta0.migadu.com [91.218.175.182]) (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 7432F275855 for ; Mon, 23 Jun 2025 18:49:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750704552; cv=none; b=JIwBkz89Rk8+6mS4ssR/im3vgG6ABvh49wfXUopIaa4sC5yZhJvu9LSH1tKbSW/0t9b/UNNgZbrXwhu+1UyR8mygudWneJS6pXTNcqD5fzKZu3iz0EHDUWJQb5WUgajllpg2KI1Qu+QgIwXRI2b3ZNOmCUSnFtxvBXyDblF0ElE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750704552; c=relaxed/simple; bh=kFM0TNlX/U+yDgwFjIEMNOTe+9mt+VLKNv3TBfQoHu0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=KRVwJRlgrNHl+f6dJjT1X6jVQ3xW/Yrh3KK6BfYTgiYua4Zs2zDdIVpAIzOtQ0P4l2xStnQSK+bNx9lGKALNhW+Qob7pA3erqlwT3ogPx4mywgBMGE1nZFhQR1IEgBODsvdhDeADbLkp+tjDtzN4pfkjB68DEg07FdaoUXUS6sU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=PXieTfFN; arc=none smtp.client-ip=91.218.175.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="PXieTfFN" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1750704537; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gPeP8du2qBa6yFfD4N13fXz74Emk3SySRJAz2DZwT+g=; b=PXieTfFNnH2x0MB6xi3e+6LGZLqrOxLZI3i0CcOdyGfCvdjd7oBe6wW/zwNLrAyB877f21 ejPCyCi4UknfuJ1Xgqn8myevhtFm14NvQVD9OS0Q/Am4s6Dc+xdwaO3JAtIQ1BLfv3DdhU bKacHtVK2GuqyI7UQ2SIZtfsr58L+QE= Date: Mon, 23 Jun 2025 14:48:53 -0400 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH net 4/4] net: axienet: Split into MAC and MDIO drivers To: Andrew Lunn Cc: Radhey Shyam Pandey , Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, Greg Kroah-Hartman , Michal Simek , Saravana Kannan , Leon Romanovsky , Dave Ertman , linux-kernel@vger.kernel.org, Ira Weiny , linux-arm-kernel@lists.infradead.org References: <20250619200537.260017-1-sean.anderson@linux.dev> <20250619200537.260017-5-sean.anderson@linux.dev> <16ebbe27-8256-4bbf-ad0a-96d25a3110b2@lunn.ch> <0854ddee-1b53-472c-a4fe-0a345f65da65@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Sean Anderson In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 6/23/25 14:27, Andrew Lunn wrote: > On Mon, Jun 23, 2025 at 11:16:08AM -0400, Sean Anderson wrote: >> On 6/21/25 03:33, Andrew Lunn wrote: >> > On Thu, Jun 19, 2025 at 04:05:37PM -0400, Sean Anderson wrote: >> >> Returning EPROBE_DEFER after probing a bus may result in an infinite >> >> probe loop if the EPROBE_DEFER error is never resolved. >> > >> > That sounds like a core problem. I also thought there was a time >> > limit, how long the system will repeat probes for drivers which defer. >> > >> > This seems like the wrong fix to me. >> >> I agree. My first attempt to fix this did so by ignoring deferred probes >> from child devices, which would prevent "recursive" loops like this one >> [1]. But I was informed that failing with EPROBE_DEFER after creating a >> bus was not allowed at all, hence this patch. > > O.K. So why not change the order so that you know you have all the > needed dependencies before registering the MDIO bus? > > Quoting your previous email: > >> Returning EPROBE_DEFER after probing a bus may result in an infinite >> probe loop if the EPROBE_DEFER error is never resolved. For example, >> if the PCS is located on another MDIO bus and that MDIO bus is >> missing its driver then we will always return EPROBE_DEFER. > > Why not get a reference on the PCS device before registering the MDIO > bus? Because the PCS may be on the MDIO bus. This is probably the most-common case. --Sean