> It's a huge pile of tricky code we'll need to maintain. To justify its > inclusion I think we need to be confident that kasan will find a > significant number of significant bugs that > kmemcheck/debug_pagealloc/slub_debug failed to detect. I would put it differently. kmemcheck is effectively too slow to run regularly. kasan is much faster and covers most of kmemcheck. So I would rather see it as a more practical replacement to kmemcheck, not an addition. > How do we get that confidence? I've seen a small number of > minorish-looking kasan-detected bug reports go past, maybe six or so. > That's in a 20-year-old code base, so one new minor bug discovered per > three years? Not worth it! > > Presumably more bugs will be exposed as more people use kasan on > different kernel configs, but will their number and seriousness justify > the maintenance effort? I would expect so. It's also about saving developer time. IMHO getting better tools like this is the only way to keep up with growing complexity. > If kasan will permit us to remove kmemcheck/debug_pagealloc/slub_debug > then that tips the balance a little. What's the feasibility of that? Maybe removing kmemcheck. slub_debug/debug_pagealloc are simple, and are in different niches (lower overhead debugging) -Andi -- ak@xxxxxxxxxxxxxxx -- Speaking for myself only. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>