Re: Solaris developer wants a Linux Mentor for drivers.

[Neil Horman <nhorman@redhat.com>]

Alan Kilian wrote:
> 
>   Kernel folks,
> 
>     I am in the process of porting a Sun Solaris PCI bus driver
>     that I wrote over to a 2.4 kernel, and I could use a mentor
>     just to get me over the initial bumps.
> 
>     I have a module that can be loaded, and detects my card, and
>     responds to ioctl() calls properly, so I'm moving right along,
>     but I do have some problems now.
> 
>     1) If I "oops" in my module, I cannot unload it with:
>        # /sbin/rmmod sse    
>        sse: Device or resource busy
somebody is holding a reference to your device, either through your 
modules use of the MOD_INC_USE_COUNT macro (which I believe is 
depricated), or through the use of one of the macros that the kernel 
uses to prevent module remove race conditions (dev_hold is the only one 
that jumps to mind at the moment).  You can only get the module to 
remove by balancing the MOD_INC/DEC macros, or massaging your kernel to 
release any references to your module.  However, after an oops, its 
usually best practice to reboot, lest you run a kernel with corrupted 
memory somewhere.

> 
>        I have only figured out that a reboot cleans things up again.
> 
>     2) An example of using pci_ops read_dword() would be superb.
> 
I don't believe you call the operation in a pci_ops structure directly. 
  check the kernel for references to 
pci_[read|write]_config_[byte|word|dword] instead.

HTH
Neil
>     By the way, this development environment is really slick
>     compared to Solaris. When I "oops" in Solaris, the kernel
>     panics and I'm in for a messy fsck on the way back up. This
>     is a great improvement.
> 
>     Thanks in advance for any help any of you may provide.
> 
>     After this, there will be one more Linux PCI bus driver developer
>     in the world, and that can't be a bad thing.
> 
>                           -Alan
> 


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  *Neil Horman
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