Created attachment 42411 [details]
dmesg

Yeah I've seen this too, very annoying.  I don't believe it was anything in nouveau directly that causes it.  Any chance you could bisect it back to find the offending commit?

looks like thats the culprit :

commit 3d58ec154bc87b206a3439f064e1c8aa6090c1ee
Author: Lucas Stach <dev@lynxeye.de>
Date:   Thu Jan 6 20:29:53 2011 +0100

    drm/nouveau: fix hwmon device binding
    
    Bind the hwmon structs to nouveau device kobj. This makes sure
    the hwmon files are created in the device subdir in line with
    all other hwmon drivers.
    
    Signed-off-by: Lucas Stach <dev@lynxeye.de>
    Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_pm.c b/drivers/gpu/drm/nouveau/nouveau_pm.c
index d938141..fb846a3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_pm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_pm.c
@@ -422,8 +422,7 @@ nouveau_hwmon_init(struct drm_device *dev)
                return ret;
        }
        dev_set_drvdata(hwmon_dev, dev);
-       ret = sysfs_create_group(&hwmon_dev->kobj,
-                                       &hwmon_attrgroup);
+       ret = sysfs_create_group(&dev->pdev->dev.kobj, &hwmon_attrgroup);
        if (ret) {
                NV_ERROR(dev,
                        "Unable to create hwmon sysfs file: %d\n", ret);

Oh. This seems my fault. I have not tested with reloading, sorry.

I will look into this today and try to fix it without the need to revert this commit.

Patch is on the mailing list.
Again sorry for your inconvenience and thanks for your time bisecting this.

I will leave this bug open till the fix is in master.

I wake up and get the same fix from 2 different persons :)
joi on IRC 12h ago :
00:39   joi >> shining^: http://paste.pocoo.org/show/328947/ <- should fix it

I just applied and it does work, so thank you both.

Fixed in nouveau master.