Re: 2.6.34-rc1: ACPI: BUG: key f71f0168 not in .data!

[Matthew Wilcox <matthew@wil.cx>]

On Fri, Mar 12, 2010 at 08:58:36PM -0800, Eric W. Biederman wrote:
> The root problem is that we occasionally have unrecognized deadlocks
> on the sysfs attributes.
> 
> For 2.6.33 I managed to get lockdep mostly working but there the way
> I did it generated a lot of false positives.
> 
> For 2.6.34 I reworked the sysfs lockdep handling to remove the false
> positives by treating each sysfs attribute as it's own class.  Most
> sysfs attributes are declared statically and don't need any
> initialization.  Unfortunately there are a handful of dynamically
> allocated sysfs attributes that do need initialization.
> 
> This patch is a fix to get one of those last handful of dynamically
> allocated sysfs attributes that I missed and apparently do not
> exist in my test system.

There's a few more than this showing up on my laptop.  Looking in dmesg,
the first gets a backtrace:

[    1.034471] BUG: key f6a26638 not in .data!
[    1.034600] ------------[ cut here ]------------
[    1.034736] WARNING: at kernel/lockdep.c:2706 lockdep_init_map+0xd1/0x40c()
[    1.034867] Hardware name: LifeBook P8010
[    1.034993] Modules linked in:
[    1.035170] Pid: 1, comm: swapper Not tainted 2.6.34-rc1-00005-g522dba7 #80
[    1.035300] Call Trace:
[    1.035428]  [<c102caba>] warn_slowpath_common+0x60/0x90
[    1.035561]  [<c102caf7>] warn_slowpath_null+0xd/0x10
[    1.035694]  [<c104fa6a>] lockdep_init_map+0xd1/0x40c
[    1.035827]  [<c10de32a>] ? sysfs_new_dirent+0x73/0xdb
[    1.035959]  [<c10ddc56>] sysfs_add_file_mode+0x4c/0x88
[    1.036132]  [<c10ddca0>] sysfs_add_file+0xe/0x13
[    1.036264]  [<c10ddd32>] sysfs_create_file+0x20/0x22
[    1.036394]  [<c11ee279>] device_create_file+0x13/0x15
[    1.036528]  [<c129246e>] thermal_zone_device_register+0x3d0/0x5db
[    1.036662]  [<c11b160f>] acpi_thermal_add+0x1f6/0x42d

Subsequent ones don't:

[    1.039072] BUG: key f6a26668 not in .data!
[    1.039220] BUG: key f6a2f488 not in .data!
[    1.039358] BUG: key f6a2f408 not in .data!
[    1.039571] thermal LNXTHERM:01: registered as thermal_zone0
[    1.039719] ACPI: Thermal Zone [TZ00] (27 C)
[    1.040515] BUG: key f6a18e38 not in .data!
[    1.040648] BUG: key f6a18e68 not in .data!
[    1.040800] BUG: key f6a9ef88 not in .data!
[    1.040941] BUG: key f6a9ef08 not in .data!
[    1.041185] thermal LNXTHERM:02: registered as thermal_zone1

[   25.196957] iwlagn 0000:14:00.0: firmware: requesting iwlwifi-4965-2.ucode
[   25.197163] BUG: key f663393c not in .data!
[   25.217340] iwlagn 0000:14:00.0: loaded firmware version 228.57.2.21

-- 
Matthew Wilcox				Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."