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 31E3821348 for ; Mon, 28 Jul 2025 22:34:02 +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=1753742043; cv=none; b=shDu14tsMfzhf+x1kcSpq8BLqI9ccvbL9LLNVE8SW03nk70XER7fvE/BKDMPHn3j1Umo6uUoCEYFACkhF+vqSm/Pb4O1L4BdmzG8ATwT/MKcuZTiGZUhpYACcTFRPyvyf2SavhYrGAB00rQmhybhZmML11S57pfpO0opGdJQ5iU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753742043; c=relaxed/simple; bh=8a2Y93oHH/OSh9XjEyyBAAxmZiTUjcXf/ZOnnwUBTK8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=GoJyknb0l/SnR/UsjfI22UxarRTsA/ImJO0IxpQREm9e7jd4jEUPxz5exuq1oZZNz8+XqA/ZA8Pna1CKyUMRAD6/s9E4q5NFD/QFaD4gpBzHywMgDNwWwCm5Q4nrIDvczoXPh263oWSvKaK+LBiVtqyZ5btaTFnWZukFkPTxqW0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=l4vpMbvS; 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="l4vpMbvS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4A3BAC4CEE7; Mon, 28 Jul 2025 22:34:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753742042; bh=8a2Y93oHH/OSh9XjEyyBAAxmZiTUjcXf/ZOnnwUBTK8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=l4vpMbvS9ikuZ3UxCF1E2fplBB7lTBaFvxF04UZnb8npMgZ6CDkTwGH6Mw0CMt0Jb BPvxvtUPzvpuzQBXIH3ezEGi2YY8mSDQcc9KXjvbujM0biQZH+ryS0FFyppuxGL3u0 q9xEqQyBWgbKkSvPIQ98H0LQq3kpFEx+DPTy9cU6ce/AOfZaHtoWBaFljzfn8PFdOx +tgeeiCvA9DkZb7NgneuBhPdXg5nBpIEbmBc/+LGpgGlFrikUaSLjIwSjzz2pZKiV0 uxX9Bdexq33rMTQMtnJQJDPpJNLGXcGJhAD6D4D1Iy6oWSaEnzSECCckFwJT5jVzCk GiBrw4lxiFzHw== Message-ID: <5143bbee-697b-4357-9645-10f38296b561@kernel.org> Date: Tue, 29 Jul 2025 07:33:59 +0900 Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Regression on linux-next (next-20250708) To: "Borah, Chaitanya Kumar" Cc: "intel-gfx@lists.freedesktop.org" , "intel-xe@lists.freedesktop.org" , linux-ide@vger.kernel.org, mika.westerberg@intel.com, anshuman.gupta@intel.com, "Kurmi, Suresh Kumar" , "Saarinen, Jani" , lucas.demarchi@intel.com References: <07563042-6576-41cd-9a95-de83cfc95de1@intel.com> Content-Language: en-US From: Damien Le Moal Organization: Western Digital Research In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/29/25 01:24, Borah, Chaitanya Kumar wrote: > > > On 7/28/2025 9:41 AM, Damien Le Moal wrote: >> On 7/25/25 3:43 PM, Borah, Chaitanya Kumar wrote: >>> For some context in our kms_pm_rpm tests, we enable min_power policy for SATA >>> so that we can reach deep runtime power states and restore the original policy >>> after finishing. [5][6] >>> >>> IIUC, the above change is based on spec and not something which can be >>> reverted. So as I see it, we have to drop this code path for external ports. >>> However I am not sure if we can achieve deep power states without enforcing it >>> through the sysfs entry. >>> >>> Atleast for the basic-rte subtest, the test passes if we comment out the >>> functions controlling the SATA ports. We will need more testing to determine if >>> this approach work. Any thoughts on it? >>> >>> Also, are there other ways to detect a port is external other than receiving >>> EOPNOTSUPP on the sysfs write? >> >> The attached patch adds the "link_power_management_supported" sysfs device >> attribute for drives connected to AHCI. Would that work for you ? >> > > Yes this could work. I quickly hacked the test to ignore writing policy > if this file returns 0. > > Here is the state of the machine I am testing on. > > /sys/class/scsi_host/host0/link_power_management_supported: 0 > /sys/class/scsi_host/host1/link_power_management_supported: 0 > /sys/class/scsi_host/host2/link_power_management_supported: 0 > /sys/class/scsi_host/host3/link_power_management_supported: 0 > /sys/class/scsi_host/host4/link_power_management_supported: 1 > /sys/class/scsi_host/host5/link_power_management_supported: 1 > /sys/class/scsi_host/host6/link_power_management_supported: 1 > /sys/class/scsi_host/host7/link_power_management_supported: 1 Looks good. My test machine looks exactly like this too. I will send out this patch as it is useful anyway regardless of external/hotplug ports since not all adapters/drives support LPM. When posting this, can I tag it as a solution to the regression ? And in addition to this patch, I will work on a flexible way of ignoring hotplug. -- Damien Le Moal Western Digital Research