verify_area performs any checks needed for it to be safe to use the _copy forms of copy_*_user. What that does varies. The normal Linux approach is
verify_area does access_ok which checks the address is a kernel view of a user space address. _copy* functions use the MMU to fault any illegal access beyond that. On some platforms you cant use the mmu so verify_area does more work, on others its using stuff like space registers and verify_area is a nop. copy_from_user sorts out the whole thing itself. In general __copy_from_user and verify_area isnt a win, except if you do lots of small copies to/from the same area, which is often a bad idea anyway. Alan ------------------------------------------------------- This SF.net email is sponsored by: SlickEdit Inc. Develop an edge. The most comprehensive and flexible code editor you can use. Code faster. C/C++, C#, Java, HTML, XML, many more. FREE 30-Day Trial. www.slickedit.com/sourceforge _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
