From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [PATCH AUTOSEL for 4.14 065/110] led: core: Fix brightness setting when setting delay_off=0 Date: Tue, 13 Mar 2018 08:50:22 +0100 Message-ID: <20180313075022.GA13394@amd> References: <20180204003029.2lkcmh6wvzpnlrls@sasha-lappy> <20180204090531.GA29468@amd> <20180204111500.GB14797@kroah.com> <20180204171736.GA1388@amd> <20180206020210.m6gl7vai4p6azb6s@sasha-lappy> <713113d8-7662-d80c-c62f-af020469d0bf@gmail.com> <20180312152811.GB16944@kroah.com> <5747831a-b237-aa2c-cb47-9773cd2b5956@universe-factory.net> <0cd72fe4-2b98-e6f7-6ae7-530524786cec@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="82I3+IH0IqGh5yIs" Return-path: Content-Disposition: inline In-Reply-To: <0cd72fe4-2b98-e6f7-6ae7-530524786cec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Jacek Anaszewski Cc: Matthias Schiffer , Greg KH , Sasha Levin , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Matthieu CASTET , "linux-leds@vger.kernel.org" List-Id: linux-leds@vger.kernel.org --82I3+IH0IqGh5yIs Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > > At least 7b6af2c531 ("leds: core: Fix regression caused by commit > > 2b83ff96f51d") is missing, causing visible regressions (LEDs not workin= g at > > all) on some OpenWrt devices. This was fixed in 4.4.121 by reverting the > > offending commit, but if I followed the discussion correctly, 4.9 should > > get the follow-up commit 7b6af2c531 instead (like 4.14 already did). > >=20 > > Jacek's mail I replied to mentions that eb1610b4c273 ("led: core: Fix > > blink_brightness setting race") should be included in 4.9 as well, but I > > don't know the impact of the issue it fixes. >=20 > It doesn't fix any reported issue, but is just an improvement > aiming at preventing potential races while changing blink brightness. >=20 > After taking closer look it turns out that for the patches in question > to apply cleanly we need in 4.9 also a patch which introduces atomic > bit fields for blink flags. >=20 > Effectively, here is the list of patches required in 4.9 stable: >=20 > Revert "led: core: Fix brightness setting when setting delay_off=3D0" >=20 > followed by: >=20 > a9c6ce57ec ("led: core: Use atomic bit-field for the blink-flags") > eb1610b4c2 ("led: core: Fix blink_brightness setting race") > 2b83ff96f5 ("led: core: Fix brightness setting when setting delay_off=3D0= ") > 7b6af2c531 ("leds: core: Fix regression caused by commit 2b83ff96f51d") For the record... there's no serious problem in LED subsystem in v4.9. Just leave LED subsystem alone in v4.9-stable (reverting any patches that were backported by some kind of bot that did not even test them), and things will be fine. Pavel --=20 (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo= g.html --82I3+IH0IqGh5yIs Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlqngr4ACgkQMOfwapXb+vJOAwCglQhsELLghisDZKNOd4Ql6uht SQEAnA/KmCxz/hDnc1hUasIKmbEwcXD2 =LInh -----END PGP SIGNATURE----- --82I3+IH0IqGh5yIs--