Re: 2.6.21-rc4-mm1

[Andrew Morton <akpm@linux-foundation.org>]

On Fri, 23 Mar 2007 11:10:29 +0100 Cornelia Huck <cornelia.huck@de.ibm.com> wrote:

> On Thu, 22 Mar 2007 13:55:51 -0500,
> Larry Finger <larry.finger@lwfinger.net> wrote:
> 
> > Cornelia Huck wrote:
> > > On Thu, 22 Mar 2007 07:23:06 -0500,
> > > 
> > > This would indicate that dev_uevent had been called. But how could
> > > kobject_uevent then return an error without moaning about an uevent()
> > > error code? Maybe the following debug patch could shed some light on
> > > this (all moaning is prefixed with kobject_uevent_env, so it should be
> > > easy to spot)...
> > 
> > I applied the debug patch, but I don't see any error codes being returned. This time I also got the
> > General Protection Faults. An excerpt of the log is attached.
> 
> Hm, I think I have an idea about what happened.
> 
> The firmware class tried to suppress the first KOBJ_ADD uevent by
> returning -ENODEV in firmware_uevent if FW_STATUS_READY was not set.
> This only worked as long as the return code of kobject_uevent was not
> checked in device_add. hack-to-make-wireless-work.patch made that first
> uevent return successfully, but this possible triggered some udev rule
> too early, leading to firmware load failures.
> 
> The following (completely untested) patch uses uevent_suppress to stop
> the uevent from being generated during device_add. Does this work for
> you?
> 
> ---
>  drivers/base/firmware_class.c |    2 ++
>  1 file changed, 2 insertions(+)
> 
> --- linux-2.6.orig/drivers/base/firmware_class.c
> +++ linux-2.6/drivers/base/firmware_class.c
> @@ -333,6 +333,7 @@ static int fw_register_device(struct dev
>  	f_dev->parent = device;
>  	f_dev->class = &firmware_class;
>  	dev_set_drvdata(f_dev, fw_priv);
> +	f_dev->uevent_suppress = 1;
>  	retval = device_register(f_dev);
>  	if (retval) {
>  		printk(KERN_ERR "%s: device_register failed\n",
> @@ -385,6 +386,7 @@ static int fw_setup_device(struct firmwa
>                  set_bit(FW_STATUS_READY, &fw_priv->status);
>          else
>                  set_bit(FW_STATUS_READY_NOHOTPLUG, &fw_priv->status);
> +	f_dev->uevent_suppress = 0;
>  	*dev_p = f_dev;
>  	goto out;

hm.

Would I be right in guessing that this was all triggered by
uevent-improve-error-checking-and-handling.patch?

If so, do you think I should labour on with
uevent-improve-error-checking-and-handling.patch plus your fix, or should I
drop the lot?  (I'm inclined toward the latter, but I'm still not
sure which patch(es) need to be dropped).

Thanks.