From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-445509-1520346017-2-13413094276131161173 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='us-ascii' X-Attached: signature.asc X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1520346017; b=ww9E1i5qIiS5zQ65Oy5G44PiHyb6ZeaM2p4Wgtpdk/2aBfS I5ONkvzSm3bZEsqe0iNevfTiXLb78lqWMVbJ/VOp9RyI8pwIz5VInV7ewZgcHP4G 5gcYgGPrXYI1PCdnVkcsn0Iln9LIRatPm4vPBrTqg/cGrD/mQ8oF8rIgNgcMGbBJ b3ltetJNHENeQ73Q5JoprlTSKrQVUV6Od2k5hSXV23igYc3d3ErrunGyxp0SI2Rs w/rNDssvxpHkIF4suFejGNNbqFmpLGRezpHQaOemgtopCHGPbh3A3BpQ2wiHrNJu Y+KQ3Aw+BlJY6O47c0rBHFukPg+raIKwUsL12IQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=date:from:to:cc:subject:message-id :references:mime-version:content-type:in-reply-to:sender :list-id; s=arctest; t=1520346017; bh=6WHs0U0t1JzSW1p0l29MyjEV29 dBvELf0h8aMaKg2MM=; b=oyDRUU3gR2cR/K3vvrBab2/hbogoSLNWD4TIVbT3Iv Yv8dpeGBopAeQoreAT41xnbsAC4xc3wvhbXS1o2chRIP8g6UdfCNZQ/zdQE7okkQ 8UAjLw8bd0+V22pW+yGz7o4BUJ2GENKKj+JMKgCkzQYPOaOQwT/Pnxp3nsIW6uRm KuMOGTLZMx39BrYNKWYaDfQ1tZvbzCLOU3pTV7a+D4dS9BlfME+Z0xVPIUd+xueQ sKLIai8zYw7x7h5LdPfecZU5LeMUYvOVz119VUstSMDPsjjX80ryA+GCk85GXf8n xc3Xm+RUwXmf/2uqyiLzokFbm315TNtBK+itfGNFPuHA== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered; 1024-bit rsa key sha256) header.d=sirena.org.uk header.i=@sirena.org.uk header.b=pN50oTVT x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=20170815-heliosphere; dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=orgdomain_pass; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=kernel.org header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered; 1024-bit rsa key sha256) header.d=sirena.org.uk header.i=@sirena.org.uk header.b=pN50oTVT x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=20170815-heliosphere; dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=orgdomain_pass; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=kernel.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753243AbeCFOUP (ORCPT ); Tue, 6 Mar 2018 09:20:15 -0500 Received: from heliosphere.sirena.org.uk ([172.104.155.198]:41162 "EHLO heliosphere.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753075AbeCFOUO (ORCPT ); Tue, 6 Mar 2018 09:20:14 -0500 Date: Tue, 6 Mar 2018 14:20:12 +0000 From: Mark Brown To: Jonas Gorski Cc: Sasha Levin , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: Re: [PATCH AUTOSEL for 4.9 002/219] spi/bcm63xx: make spi subsystem aware of message size limits Message-ID: <20180306142012.GB13586@sirena.org.uk> References: <20180303222716.26640-1-alexander.levin@microsoft.com> <20180303222716.26640-2-alexander.levin@microsoft.com> <20180305102310.GC8588@sirena.org.uk> <20180305200744.afw64js6wnmyfqrb@sasha-lappy> <20180305203533.GP8588@sirena.org.uk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="yNb1oOkm5a9FJOVX" Content-Disposition: inline In-Reply-To: X-Cookie: DYSLEXICS OF THE WORLD, UNTIE! User-Agent: Mutt/1.9.3 (2018-01-21) Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: --yNb1oOkm5a9FJOVX Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Mar 06, 2018 at 02:42:43PM +0100, Jonas Gorski wrote: > On 5 March 2018 at 21:35, Mark Brown wrote: > > It's exposing more capability information but it's in the "how did this > > ever work without the fix" range, and I'd worry that this might cause us > > to do something like start exercising handling code in client drivers > > that had never been tested. Not that I can immediately see any client > > drivers in mainline that actually pay attention... :/ > I would assume that most spi client drivers use short messages, so > they aren't affected unless the max message size is really short. > m25p80 on the other hand will do arbitrarily large transfers/reads, so > there it was supported first. There's a bunch of SPI drivers that do firmware downloads which I'd expect to be affected, the limit the device has is tiny so it's relatively easy to bump into it. It's very rare for devices to be so limited so unfortunately client drivers don't generally check though. --yNb1oOkm5a9FJOVX Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAlqeo5sACgkQJNaLcl1U h9AQlAf+PKFnqNyb0gydb+DCmkATY/te2KH/VI8Vgq9KpYSJpDIlHPvRjq0PC6LZ WFxb2+swqs0nOo6zDvMulFnxGt4oP5DimepjOm8ttZj54Htn8vUE+A/p3u6bD9fm 7u9X/O/RmtWDhwuANqxrjd4WAKSYv291ImqfOqSZ4D17PxuPZz9PMvxKstq/kIyD QhqBxiBey/6wMTLatm4qdmbqoKVn5RdOdWZN7w12w6YBb41H95VL4q/AHFthartp uocMEmMJf5omrqueS5QMzIDiS2haHE0Ldnuf1Q2rLaSM/+rkgICe5Ii7BOAvAH76 ORHfnPgSOlEBM63AyBr+rW65Bz24eg== =i/6N -----END PGP SIGNATURE----- --yNb1oOkm5a9FJOVX--