On 2011-05-30 17:10, Roedel, Joerg wrote: > On Mon, May 30, 2011 at 11:04:02AM -0400, Jan Kiszka wrote: >> On 2011-05-30 16:38, Nadav Har'El wrote: >>> On Mon, May 30, 2011, Jan Kiszka wrote about "drop -enable-nesting (was: [PATCH 3/7] cpu model bug fixes and definition corrections...)": >>>> On 2011-05-30 10:18, Roedel, Joerg wrote: >>>>> On Sat, May 28, 2011 at 04:39:13AM -0400, Jan Kiszka wrote: >>>>> >>>>>> Jïrg, how to deal with -enable-nesting in qemu-kvm to align behavior >>>>>> with upstream? >>>>> >>>>> My personal preference is to just remove it. In upstream-qemu it is >>>>> enabled/disabled by +/-svm. -enable-nesting is just a historic thing >>>>> which can be wiped out. >>> >>> "-enable-nesting" could remain as a synonym for enabling either VMX or SVM >>> in the guest, depending on what was available in the host (because KVM now >>> supports both nested SVM and nested VMX, but not SVM-on-VMX or vice versa). >> >> Why? Once nesting is stable (I think SVM already is), there is no reason >> for an explicit enable. And you can always mask it out via -cpu. >> >> BTW, what are the defaults for SVM right now in qemu-kvm and upstream? >> Enable if the modeled CPU supports it? > > qemu-kvm still needs -enable-nesting, otherwise it is disabled. Upstream > qemu should enable it unconditionally (can be disabled with -cpu ,-svm). Then let's start with aligning qemu-kvm defaults to upstream? I guess that's what the diff I was citing yesterday is responsible for. In the same run, -enable-nesting could dump a warning on the console that this switch is obsolete and will be removed from future versions. For VMX, I would suggest to keep it off by default until it matured, asking the user to issue -cpu ...,+vmx. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- 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
