On Mon, Mar 14, 2016 at 9:58 AM, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Mar 14, 2016 9:53 AM, "Andy Lutomirski" <luto@xxxxxxxxxxxxxx> wrote: >> >> Can you clarify? KVM uses the native version, and the native version >> only oopses with this series applied if panic_on_oops is set. > > Can we please remove that idiocy? > > There is no reason to panic whatsoever. Seriously. What's the upside of that > logic? I imagine that people who set panic_on_oops want their systems to stop running user code if something happens that could corrupt the state or if there's any sign that user code is trying some non-deterministic exploit. So I'm guessing that they'd want this type of "the kernel screwed up -- abort" to actually result in a panic. As a concrete, although somewhat silly, example, suppose that a write to MSR_SYSENTER_STACK fails. If that happened, then user code could subsequently try to take over the kernel by evil manipulation of TF and/or perf. I'd be okay with removing this too, though, since arranging for MSR access to fail seems unlikely as an exploit vector. Borislav: SUSE actually uses panic_on_oops, right? What's their goal? --Andy -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
