Re: [2.5 PATCH] bug if cpufreq driver initialization fails

Russell King (rmk@arm.linux.org.uk)
Sun, 15 Jun 2003 19:16:50 +0100


On Sun, Jun 15, 2003 at 02:04:36PM -0400, Samuel Thibault wrote:
> I hence modified drivers/base/sys.c to have sysdev_driver_register()
> fail as well, and then I also had to modify kernel/cpufreq.c, because
> this failure did not imply a setting cpufreq_driver to NULL (preventing
> me from reinsmoding speedstep-ich: EBUSY)

Unfortunately, you created a by by doing so. Eg:

- you have 3 devices on kset.list.
- you successfully register 2 of them with a driver.
- you fail one.
- sysdev_driver_register returns failure.
- module is unloaded while other parts of the kernel have references into
the driver.
- the kernel oopses.

> I'd also suggest that the speedstep drivers printks something if
> everything went ok (including the cpufreq_frequency_table_cpuinfo()
> call), the low & high speed for instance, just to be sure everything
> went ok

IMO its better to printk something on failure.

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html

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