Ingo Molnar <mi...@kernel.org> writes: > * Steven Rostedt <rost...@goodmis.org> wrote: > >> On Fri, 04 Dec 2015 12:05:12 +1030 >> Rusty Russell <ru...@rustcorp.com.au> wrote: >> >> > This is clever, but I would advise against such subtle code. We will >> > never be >> > able to remove this code once it is in. >> > >> > Would suggest making the non-CPUMASK_OFFSTACK stubs write garbage into the >> > cpumasks instead, iff !(flags & __GFP_ZERO). >> >> I actually thought of the same thing, but thought it was a bit harsh. If >> others >> think that's a better solution, then I'll submit a patch to do that. > > That just makes things more fragile - 'garbage' will spread the breakage, and > if > the breakage is subtle, it will spread subtle breakage. > > So why not use a kzmalloc_node() [equivalent] call instead of kmalloc_node(), > to > make sure it's all zeroed instead of uninitialized?
OTOH, why not make *every* kmalloc a kzmalloc? The issue here is not that the issue is subtle (not using a zeroing allocator is a pretty clear bug), it's that it's papered over by the normal config. If we had a config option already to garbage-fill allocations, it'd be a simple solution. I don't think there are great answers here. But adding more subtle zeroing semantics feels wrong, even if it will mostly Just Work. Cheers, Rusty. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
