Date: Fri, 13 Dec 2013 17:09:20 -0500 From: John Baldwin <jhb@freebsd.org> To: Neel Natu <neelnatu@gmail.com> Cc: "freebsd-virtualization@freebsd.org" <virtualization@freebsd.org> Subject: Re: Panic starting a bhyve guest after resume Message-ID: <201312131709.20264.jhb@freebsd.org> In-Reply-To: <CAFgRE9Ej9O7jMBcE0oqshd_-59aPskhN81FoCsDbaEjdcxhJAA@mail.gmail.com> References: <201312121511.38608.jhb@freebsd.org> <CAFgRE9Ej9O7jMBcE0oqshd_-59aPskhN81FoCsDbaEjdcxhJAA@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thursday, December 12, 2013 4:00:08 pm Neel Natu wrote: > Hi John, > > On Thu, Dec 12, 2013 at 12:11 PM, John Baldwin <jhb@freebsd.org> wrote: > > If I suspend and resume my laptop and then try to start a guest after the > > resume, I get an odd panic. It generates a privileged instruction fault (in > > kernel mode) for 'vmclear'. I've checked CR4 and it claims that VMXE is set. > > I dont have any other ideas off the top of my head on what I should be poking > > at? It looks like we read a bunch of MSRs in vmx_init(), but we don't write > > to them, and all vmx_enable() does on each CPU is set VMXE in CR4 from what I > > can tell. > > > > It also does a "vmxon" on each logical cpu which may also need to be > done after a resume. Ah, yes it does. That was sufficient both for starting a new guest after resume and even doing a suspend/resume while a guest was active (and the guest continued to run fine). I have a hacky patch for this. One, it includes both a suspend and resume hook for VMM, though for my testing I only needed a resume hook to invoke vmxon. Second, the name of vmx_resume2() is a total hack (because vmx_resume() was already taken. I think for now if I were to commit this, I'd just add the resme hook and maybe call the Intel method vmx_reset() or vmx_restore()? http://people.freebsd.org/~jhb/patches/bhyve_resume.patch -- John Baldwin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201312131709.20264.jhb>