2.2 changes kernelversions I don't know the entire kernel well enough do document all of the changes. In the course of converting the examples (or actually, adapting Emmanuel Papirakis's changes) I came across the following differences. I listed all of them here together to help module programmers, especially those who learned from previous versions of this book and are most familiar with the techniques I use, convert to the new version. An additional resource for people who wish to convert to 2.2 is located on Richard Gooch's site . asm/uaccess.h asmuaccess.h put_user get_user structurefile_operations flush close read write ssize_t proc_register_dynamic signals queue_task_irq queue_task interrupts irqs moduleparameters module parameters MODULE_PARM Symmetrical Multi-Processing SMP asm/uaccess.h If you need put_user or get_user you have to #include it. get_user In version 2.2, get_user receives both the pointer into user memory and the variable in kernel memory to fill with the information. The reason for this is that get_user can now read two or four bytes at a time if the variable we read is two or four bytes long. file_operations This structure now has a flush function between the open and close functions. close in file_operations In version 2.2, the close function returns an integer, so it's allowed to fail. read,write in file_operations The headers for these functions changed. They now return ssize_t instead of an integer, and their parameter list is different. The inode is no longer a parameter, and on the other hand the offset into the file is. proc_register_dynamic This function no longer exists. Instead, you call the regular proc_register proc_register and put zero in the inode field of the structure. Signals The signals in the task structure are no longer a 32 bit integer, but an array of _NSIG_WORDS _NSIG_WORDS integers. queue_task_irq Even if you want to scheduale a task to happen from inside an interrupt handler, you use queue_task, not queue_task_irq. Module Parameters You no longer just declare module parameters as global variables. In 2.2 you have to also use MODULE_PARM to declare their type. This is a big improvement, because it allows the module to receive string parameters which start with a digits, for example, without getting confused. Symmetrical Multi-Processing The kernel is no longer inside one huge spinlock, which means that kernel modules have to be aware of SMP.