On Wed, 2 May 2018, John Stoffel wrote: > You miss my point, which is that there's no explanation of what the > difference is between SLAB and SLUB and which I should choose. The > same goes here. If the KConfig option doesn't give useful info, it's > useless. So what, we could write explamantion of that option. > >> Now I also think that Linus has the right idea to not just sprinkle > >> BUG_ONs into the code, just dump and oops and keep going if you can. > >> If it's a filesystem or a device, turn it read only so that people > >> notice right away. > > Mikulas> This vmalloc fallback is similar to > Mikulas> CONFIG_DEBUG_KOBJECT_RELEASE. CONFIG_DEBUG_KOBJECT_RELEASE > Mikulas> changes the behavior of kobject_put in order to cause > Mikulas> deliberate crashes (that wouldn't happen otherwise) in > Mikulas> drivers that misuse kobject_put. In the same sense, we want > Mikulas> to cause deliberate crashes (that wouldn't happen otherwise) > Mikulas> in drivers that misuse kvmalloc. > > Mikulas> The crashes will only happen in debugging kernels, not in > Mikulas> production kernels. > > Says you. What about people or distros that enable it > unconditionally? They're going to get all kinds of reports and then > turn it off again. Crashing the system isn't the answer here. I've made that kvmalloc bug too (in the function dm_integrity_free_journal_scatterlist). I'd much rather like if the kernel crashed (because then - I would fix the bug). The kernel didn't crash and the bug sneaked into the official linux tree, where may be causing random crashes for other users. Mikulas
