From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roman Mamedov Subject: Re: [2.6.37 -> 2.6.38 regression] "mv64xxx: I2C bus locked, block: 1, time_left: 0" every few seconds Date: Tue, 31 Jan 2012 02:53:29 +0600 Message-ID: <20120131025329.30e73a3f@natsu> References: <20120101042401.4bef017e@natsu> <20120101073255.GA2402@elie.hsd1.il.comcast.net> <20120108004502.GA20549@ericsson.com> <20120131024429.2affbd1c@natsu> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/HHMXivSGeXY7.O3THjI8M4e"; protocol="application/pgp-signature" Return-path: In-Reply-To: <20120131024429.2affbd1c@natsu> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roman Mamedov Cc: Guenter Roeck , Jonathan Nieder , Arnaud Patard , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Manuel Roeder , Michael Ott , Rodolfo Giometti , Mauro Barella List-Id: linux-i2c@vger.kernel.org --Sig_/HHMXivSGeXY7.O3THjI8M4e Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 31 Jan 2012 02:44:29 +0600 Roman Mamedov wrote: > On Sat, 7 Jan 2012 16:45:02 -0800 > Guenter Roeck wrote: >=20 > > > - Michael Ott reported with Debian kernel 2.6.38-3 (which is closely > > > based on stable v2.6.38.2): > > >=20 > > > syslog tell me every few seconds: > > > i2c i2c-0: mv64xxx: I2C bus locked, block: 1, time_left: 0 > > >=20 > > > - Manuel Roeder reported the same and found that upstream v2.6.38 > > > triggers the problem and v2.6.37.6 does not. > > >=20 > > > - Roman Mamedov finds the bug present in Debian 3.1.6-1 (which > > > is closely based on stable v3.1.6) and Debian 2.6.37-2 (based on > > > stable v2.6.37.2) but not Debian 2.6.37-1 (based on mainline > > > v2.6.37). > > >=20 > > > The regression range described above seems a little inconsistent to > > > me, so maybe there's something more going on. > > >=20 > > Points to commit eda6bee6c7e67b5bd17bdbced0926f5687f686d5 (i2c-mv64xxx:= send repeated START > > between messages in xfer). Maybe you can back it out and see if it make= s a difference. >=20 > Hello, >=20 > I have just confirmed that the problem still occurs in the current > 3.2.2, and is indeed solved by rolling-back the referred commit. >=20 > Should be noted that beside the "I2C bus locked" messages in dmesg, the d= escribed problem > manifested itself in the inability to read the temperature sensor value o= r adjust the fan > speed on the D-Link DNS-323. On all problematic kernels the built-in fan = of DNS-323 does not > rotate and this risks overheating the device and disks installed in it. Also if anyone decides to further debug this, I should note that once a 'problematic' kernel has booted once on the device, a full power-off seems = to be required, before a 'good' kernel can work properly. Without this, even a working kernel will manifest the same problem, it looks like something in t= he hardware gets locked-up hard and stays that way even across reboots. If someone's unaware of this, it can completely foil any attempt at git bisect= ing. --=20 With respect, Roman ~~~~~~~~~~~~~~~~~~~~~~~~~~~ "Stallman had a printer, with code he could not see. So he began to tinker, and set the software free." --Sig_/HHMXivSGeXY7.O3THjI8M4e Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEARECAAYFAk8nA0kACgkQTLKSvz+PZwiwrACfVeXUL5wCGm2XsiOYC5DstB2c ftAAn2Y4QFlNEYc5rRl9NF+I/XrkdNIn =YJ91 -----END PGP SIGNATURE----- --Sig_/HHMXivSGeXY7.O3THjI8M4e--