I was recently asked this question as to what are the common issues while debugging linux device drivers in an interview. I came up with the following list.

1. Use of Uninitialized variables.
2. Accessing array out of bounds.
3. Improper locking.
4. Using sleep functions in spinlocks.
5. Referring to unauthorized memory(Normal segmentation fault).
6. stack overflow
7. No permission for accessing some ports/devices through its data structures.
8. Inappropriate use of synchronization primitives.
9. Inappropriate sizes of structures due to padding for alignment by compilers.
10. DMA device given virtual address instead of physical address.

I am just a beginner in device driver field. I am curious to learn and request expert/experienced people here to add/delete/modify my list items with some explanation if possible.

Many of the problems you mention can at least generate a warning at compile time if you put the right compiler options (1, partially 2, partially 9). Some others can be catched with the kernel debugging options (3, 4, 7, 8, 10). I mostly agree with your list, would just add some details. For example, there are more types of addresses than virtual and physical (you have the bus address, user address too). I'd merge also your points 3, 4 and 8.

My list is:
* Mistakes between user, kernel, physical and bus addresses
* Not adapted locking methods: spinlocks instead of mutexes for example
* Race conditions on multicore systems
* Problems in locking user accesses to the driver (locking special file operations for example)
* Use after (k/v)free
* Reference counter problems
* Errors in manual offset calculations
* Different problems when freeing the resources at module unload
* Not checking error codes from called functions
* Not taking into account the errors that may be signalled by the hardware
* Asuming that the hardware will always work correctly
* Not checking data passed by the user application

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Thanks a lot [Mara]!. It definitely Help!!. Thanks for your time.