From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: openbsd system_powerdown: "KVM internal error. Suberror: 1"
Date: Mon, 21 Mar 2011 11:57:20 +0200
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Cc: Michael Tokarev <mjt@tls.msk.ru>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	KVM list <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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On Mon, Mar 21, 2011 at 11:43:32AM +0200, Avi Kivity wrote:
> >47965.428797: kvm_mmio: mmio read len 4 gpa 0xbfff4 val 0x0
> >47965.428797: kvm_entry: vcpu 0
> >47965.428798: kvm_exit: reason npf rip 0xd020203c
> >47965.428798: kvm_page_fault: address bfff8 error_code 4
> >47965.428799: kvm_emulate_insn: 0:d020203c: 58 (prot32)
> 
> That's a POP instruction.  So openbsd mapped the stack into the
> framebuffer, and kvm has to emulate everything.
> 
IIRC openbsd had always have this problem with powerdown. Last time
I looked at it I found that when openbsd receives ACPI interrupt it
enters some kind of interrupt injection loop where with each received
interrupt stack grows a little bit. When stack starts to overlap with
frame buffer emulation error happens. May be something wrong with our MP
tables, but I couldn't figure what.

> Please post a complete binary trace from bootup until the
> host_state_reload issue appears.
> 
> >47965.428799: kvm_mmio: mmio unsatisfied-read len 4 gpa 0xbfff8 val 0x0
> >47965.428801: kvm_mmio: mmio read len 4 gpa 0xbfff8 val 0x30
> >47965.428801: kvm_entry: vcpu 0
> >47965.428802: kvm_exit: reason vintr rip 0xd0202041
> >47965.428802: kvm_inj_virq: irq 81
> >47965.428802: kvm_inj_virq: irq 81
> >47965.428803: kvm_entry: vcpu 0
> >47965.428803: kvm_exit: reason npf rip 0xd0202041
> >47965.428804: kvm_page_fault: address bfffc error_code 6
> >47965.428804: kvm_emulate_insn: 0:d0202041: cf (prot32)
> >47965.428805: kvm_emulate_insn: 0:d0202041: cf (prot32) failed
> 
> We don't emulate IRET-with-mmio-stack.
> 

--
			Gleb.