From what I recall something like 50% of the code is for device drivers, though there is interesting stuff going elsewhere. LWN covers it pretty well (in fact n

From what I recall something like 50% of the code is for device drivers, though there is interesting stuff going elsewhere. LWN covers it pretty well (in fact nowhere else really does at all) http://lwn.net/Kernel/ http://lwn.net/Kernel/ Also, those stats don't take into how used something is. You can dump 200k lines for a device only used by 0.1% of users, yet if you wrote something of 2k lines, used by every user (scheduling/filesystem etc.) you wouldn't make the table, even though your impact is greater.