From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9CC03C433FE for ; Mon, 17 Oct 2022 12:47:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230517AbiJQMq7 (ORCPT ); Mon, 17 Oct 2022 08:46:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230482AbiJQMqn (ORCPT ); Mon, 17 Oct 2022 08:46:43 -0400 Received: from jabberwock.ucw.cz (jabberwock.ucw.cz [46.255.230.98]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 82EE35D0F7; Mon, 17 Oct 2022 05:46:35 -0700 (PDT) Received: by jabberwock.ucw.cz (Postfix, from userid 1017) id A2D9C1C0016; Mon, 17 Oct 2022 14:46:32 +0200 (CEST) Date: Mon, 17 Oct 2022 14:46:32 +0200 From: Pavel Machek To: Sasha Levin Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, sunghwan jung , Greg Kroah-Hartman , stern@rowland.harvard.edu, linux-usb@vger.kernel.org, usb-storage@lists.one-eyed-alien.net Subject: Re: [PATCH AUTOSEL 4.9 08/10] Revert "usb: storage: Add quirk for Samsung Fit flash" Message-ID: <20221017124632.GA13227@duo.ucw.cz> References: <20221013002802.1896096-1-sashal@kernel.org> <20221013002802.1896096-8-sashal@kernel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="h31gzZEtNLTqOjlF" Content-Disposition: inline In-Reply-To: <20221013002802.1896096-8-sashal@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --h31gzZEtNLTqOjlF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > From: sunghwan jung >=20 > [ Upstream commit ad5dbfc123e6ffbbde194e2a4603323e09f741ee ] >=20 > This reverts commit 86d92f5465958752481269348d474414dccb1552, > which fix the timeout issue for "Samsung Fit Flash". >=20 > But the commit affects not only "Samsung Fit Flash" but also other usb > storages that use the same controller and causes severe performance > regression. >=20 > # hdparm -t /dev/sda (without the quirk) > Timing buffered disk reads: 622 MB in 3.01 seconds =3D 206.66 MB/sec >=20 > # hdparm -t /dev/sda (with the quirk) > Timing buffered disk reads: 220 MB in 3.00 seconds =3D 73.32 MB/sec >=20 > The commit author mentioned that "Issue was reproduced after device has > bad block", so this quirk should be applied when we have the timeout > issue with a device that has bad blocks. >=20 > We revert the commit so that we apply this quirk by adding kernel > paramters using a bootloader or other ways when we really need it, > without the performance regression with devices that don't have the > issue. Re-introducing timeouts for users in middle of stable series... may not be nice. Is there better fix in a follow up to this that was not backported? I see that buffered reads got faster, but that may not really mean real performance gains... Best regards, Pavel > drivers/usb/storage/unusual_devs.h | 6 ------ > 1 file changed, 6 deletions(-) >=20 > diff --git a/drivers/usb/storage/unusual_devs.h b/drivers/usb/storage/unu= sual_devs.h > index 5a6ca1460711..8c51bb66f16f 100644 > --- a/drivers/usb/storage/unusual_devs.h > +++ b/drivers/usb/storage/unusual_devs.h > @@ -1294,12 +1294,6 @@ UNUSUAL_DEV( 0x090a, 0x1200, 0x0000, 0x9999, > USB_SC_RBC, USB_PR_BULK, NULL, > 0 ), > =20 > -UNUSUAL_DEV(0x090c, 0x1000, 0x1100, 0x1100, > - "Samsung", > - "Flash Drive FIT", > - USB_SC_DEVICE, USB_PR_DEVICE, NULL, > - US_FL_MAX_SECTORS_64), > - > /* aeb */ > UNUSUAL_DEV( 0x090c, 0x1132, 0x0000, 0xffff, > "Feiya", --=20 DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany --h31gzZEtNLTqOjlF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iF0EABECAB0WIQRPfPO7r0eAhk010v0w5/Bqldv68gUCY01OqAAKCRAw5/Bqldv6 8pcCAJ0c9IcuHaP/6hN6sPtSamTzyA6odACePR1wC4yMzQfBwOcHkfbEcIlHVfo= =wr5P -----END PGP SIGNATURE----- --h31gzZEtNLTqOjlF--