From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 4D9CC449B17; Thu, 15 Oct 2026 07:21:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792048878; cv=none; b=YFLPAHuR1QT29rcAwjrkYC99NOpaHLZU2VFccNXr8NHtkv9vF1U08r3X4jZ/13cwJkPOHcg0s5XcG5PkvyIiDZprMKK4FZOG57UPmPSTb/msuEkKJw07sKKmb1m74K70QEG8xXU9HJlq2n9afXAh45dBm7h4yci8KCU+AxuzFzg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792048878; c=relaxed/simple; bh=UnElEGL6a9K+KIwKMbc7bCLJ4t2PlJBsCdavuUdiOlo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PfiloLqXZy/CtKXISa3jKuqB67bNe38jOfuvjCz+BZEp9f+hQfutUKlFg8DnFUZ8O8AJnGgb1l6EstGbZg+munNFmoWBzjGEu4PhJ+/VdakEMnwjAHl7n4HHG+8WbhjfZNowVOo5pBNg5f2kT/im17y49AWJ+2HUgTq1qg+j7tA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Hmq21l6n; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Hmq21l6n" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ACAF01F000C4; Thu, 15 Oct 2026 07:21:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792048869; bh=YxcC0x778Ab3bAH3PuAHJ3L1E9EsN/37DGAWFayiun4=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Hmq21l6nNuAx9qwOf426Vd/0ZVKeHlw0Z7f3JlSZStncwrXpTerjJY/2IVjDxFOpP 5XYFr9a+JHfQhNAnuEq2B9GSI0DjZz2CP5AzfWBVldBbaOTOdGZ1f1fcyvviZhcNnW VJEK6NYXoSUbe1HQLa8dGA+d3Y0Yv35kw7PP6cD8rUXNsiVYadBdPsT8X0pZpTsb7X tnOG+Qv5ldOIHYhglr2nkqy7ZH5gnV8us5zV2+80xoCmrd3i9Y1z+laIo878J7uFI6 JJEzkNL7d21zqVZXvU5y7f8vzKK+FTU2pHmWgeM6ISasRmacppuGACB3FObfUCEd9M 5ayC9LoddGIDQ== Date: Thu, 15 Oct 2026 09:21:06 +0200 From: Niklas Cassel To: Damien Le Moal Cc: Kyrylo Biryuk , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4] ata: libahci: re-enable FBS after error handling on a port multiplier Message-ID: References: <20261012103917.389-1-illofspeed@gmail.com> Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Oct 15, 2026 at 07:37:45AM +0200, Damien Le Moal wrote: > On 2026/10/12 12:39, Kyrylo Biryuk wrote: > > ahci_do_softreset() disables FBS before resetting a device behind a port > > multiplier, as required by AHCI 1.2 section 9.3.9, and re-enables it only > > when that softreset succeeds. If it fails, for example because a > > hot-plugged drive is still spinning up ("softreset failed (device not > > ready)"), EH escalates to a hardreset of the PMP link, and nothing turns > > FBS back on: only ahci_pmp_attach() does, which runs at the next boot. > > The port keeps working with command-based switching until then. > > > > Seen on a Marvell 88SE9235 (1b4b:9235) with Marvell 88SM9705 port > > multipliers (1b4b:9705, in a Synology DX1222 expansion unit): after > > hot-plugging a drive, the kernel logged "FBS is disabled" followed by > > "softreset failed (device not ready)" and a PMP hardreset, and never > > "FBS is enabled" again (twice, on two different ports). > > > > At the end of ahci_error_handler(), re-enable FBS if a PMP is still > > attached and FBS is supported but disabled. > > > > Fixes: 89dafa20f3da ("ahci: disabled FBS prior to issuing software reset") > > Assisted-by: LLM > > Signed-off-by: Kyrylo Biryuk > > Looks good. > > Reviewed-by: Damien Le Moal Commit was updated to pick up Damien's tag: https://git.kernel.org/pub/scm/linux/kernel/git/libata/linux.git/commit/?id=23eab9e877497397a0e2394ee9174d576816209e Kind regards, Niklas