From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 004.mia.mailroute.net (004.mia.mailroute.net [199.89.3.7]) (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 E54EA2264CC; Wed, 30 Jul 2025 15:50:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.3.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753890656; cv=none; b=JGBNx00k+pg7bJlLbdu7/qfsxXOhBk5bfovzlm4pSokHf33UGiNDdNZn1gy80lr1cAKGxzWgyqAka1BZYBlsATLmfpabASXn0SfKEv/H5LVOZH7c6XDegXgHfpm66rVHfYnsmQ+M0qOSlLx0NkZ4JAMa5XSUVjipDPqbtKozd9Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753890656; c=relaxed/simple; bh=kfL7V5vYKGcyUdsgSYZAVpHfFn0XNAt9v1kO2jTioBo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=N5DuBVn+fZ2t1adinRkmcD2aJUkpRdUYyUzXVkvBn2b7FY2I1akt+pduiqX5x1iPTJxwKCrkZG/uyQUbh2w4EdslTaO1ltz9VSucyj01EIdGIZtqPD5TpnBjj86qEul0RjmsPfnUPiGStKtoKG1DbLV3+eKpxYgxAIyHE2pU5og= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=YqSSuGEx; arc=none smtp.client-ip=199.89.3.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="YqSSuGEx" Received: from localhost (localhost [127.0.0.1]) by 004.mia.mailroute.net (Postfix) with ESMTP id 4bscBP6Gvxzm1Hcc; Wed, 30 Jul 2025 15:50:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1753890650; x=1756482651; bh=kfL7V5vYKGcyUdsgSYZAVpHf Fn0XNAt9v1kO2jTioBo=; b=YqSSuGExBEi34YR2k64/1foM5z5U0vUnb3sM7iZs vrxmpwvb+G3EqmdRQfHISMNrmxn3pGCL8e4bzVe+VJh887DyEH1QKjwqOdu3P0Is DdthGa1XbKHLQ1pmed+wXTdcxe2GjHAbFn2vra0xhc05MzFOj/zWeUs9XVXh3uP1 D6/ulp9G4pBu77dKKlvefpmrY1hE/OL/xs8DtPBpAWa/dZLlbDRgO12322TViCQq ckydBpWN6b0QntUF6PVmx3PB6taOcq9sC0ZLTHBYNuwqFwFhx9M0mPzrTiKsSFg+ n7isLOME6qZvcOHIYZseYTF8QCDEzQ218VJwggjabBHgHQ== X-Virus-Scanned: by MailRoute Received: from 004.mia.mailroute.net ([127.0.0.1]) by localhost (004.mia [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id i9KiTDWc3FTh; Wed, 30 Jul 2025 15:50:50 +0000 (UTC) Received: from [100.66.154.22] (unknown [104.135.204.82]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 004.mia.mailroute.net (Postfix) with ESMTPSA id 4bscB22kSWzm1Hcd; Wed, 30 Jul 2025 15:50:33 +0000 (UTC) Message-ID: <08dcffa6-6cf9-4c79-8aa9-a82bd42d3932@acm.org> Date: Wed, 30 Jul 2025 08:50:32 -0700 Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4] scsi: ufs: core: Don't perform UFS clkscale if host asyn scan in progress To: =?UTF-8?B?UGV0ZXIgV2FuZyAo546L5L+h5Y+LKQ==?= , "beanhuo@micron.com" , "avri.altman@wdc.com" , "neil.armstrong@linaro.org" , "quic_cang@quicinc.com" , "quic_nitirawa@quicinc.com" , "quic_nguyenb@quicinc.com" , "quic_ziqichen@quicinc.com" , "luca.weiss@fairphone.com" , "konrad.dybcio@oss.qualcomm.com" , "mani@kernel.org" , "martin.petersen@oracle.com" , "quic_rampraka@quicinc.com" , "junwoo80.lee@samsung.com" Cc: "linux-scsi@vger.kernel.org" , =?UTF-8?B?VHplLW5hbiBXdSAo5ZCz5r6k5Y2XKQ==?= , "linux-arm-msm@vger.kernel.org" , "manivannan.sadhasivam@linaro.org" , "alim.akhtar@samsung.com" , "James.Bottomley@HansenPartnership.com" , "linux-kernel@vger.kernel.org" References: <20250522081233.2358565-1-quic_ziqichen@quicinc.com> <5f3911ffd2c09b6d86300c3905e9c760698df069.camel@mediatek.com> <1989e794-6539-4875-9e87-518da0715083@acm.org> <10b41d77c287393d4f6e50e712c3713839cb6a8c.camel@mediatek.com> <673e1960-f911-451d-ab18-3dc30abddd79@quicinc.com> <418bfbe4bfb3f04e805af8fa667144f148787aeb.camel@mediatek.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <418bfbe4bfb3f04e805af8fa667144f148787aeb.camel@mediatek.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable On 7/30/25 5:55 AM, Peter Wang (=E7=8E=8B=E4=BF=A1=E5=8F=8B) wrote: > Another idea is to only start ufshcd_devfreq_init > when shost->async_scan =3D 0. Hmm ... I don't think that this is a solution. There are multiple ways for triggering a LUN scan and my understanding is that the clock scaling code should be serialized against LUN scanning. Here is an example of how LUN scanning can be triggered from user space by writing into the 'scan' sysfs attribute, even if shost->async_scan =3D 0: echo "- - -" > /sys/class/scsi_host/host.../scan Bart.