pkg/51623: Non-0 CPUs don't properly "start" under qemu

[paul%whooppee.com@localhost]

>Number:         51623
>Category:       pkg
>Synopsis:       running qemu-x86_64 with -smp 4 - the additional CPUs don't start
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Nov 12 09:25:00 +0000 2016
>Originator:     Paul Goyette
>Release:        NetBSD 7.99.42
>Organization:
+------------------+--------------------------+------------------------+
| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
| (Retired)        | FA29 0E3B 35AF E8AE 6651 | paul at whooppee.com   |
| Kernel Developer | 0786 F758 55DE 53BA 7731 | pgoyette at netbsd.org |
+------------------+--------------------------+------------------------+
>Environment:
	
	
System: NetBSD speedy.whooppee.com 7.99.42 NetBSD 7.99.42 (TEST 2016-11-11 01:03:42) #0: Fri Nov 11 10:12:17 PHT 2016 paul%speedy.whooppee.com@localhost:/build/netbsd-local/obj/amd64/sys/arch/amd64/compile/TEST amd64
Architecture: x86_64
Machine: amd64
>Description:
Running qemu 2.7.0 from pkgsrc...

When attempting to emulate an SMP environment using "-smp 4", a NetBSD
kernel finds the additional CPUs but fails to completely "start" them.

	# qemu-system-x86_64 -nographic -m 1024 -smp 4 \
	-drive file=./work/wd0.img,index=0,media=disk,format=raw,snapshot=on

	### boot menu

	Choose an option; RETURN for default; SPACE to stop countdown.
	Option 1 will be chosen in 0 seconds.     
	type "?" or "help" for help.
	> boot -x

	### kernel boots

	ACPI: 1 ACPI AML tables successfully acquired and loaded
	efi: missing or invalid systbl
	ioapic0 at mainbus0 apid 0
	cpu0 at mainbus0 apid 0
	cpu0: 8 page colors
	cpu0: calibrating local timer
	cpu0: apic clock running at 1000 MHz
	cpu0: QEMU Virtual CPU version 2.5+, id 0x663
	cpu0: PAT enabled
	cpu1 at mainbus0 apid 1
	cpu1: 2 page colors
	cpu1: QEMU Virtual CPU version 2.5+, id 0x663
	cpu1: PAT enabled
	cpu2 at mainbus0 apid 2
	cpu2: 2 page colors
	cpu2: QEMU Virtual CPU version 2.5+, id 0x663
	cpu2: PAT enabled
	cpu3 at mainbus0 apid 3
	cpu3: 2 page colors
	cpu3: QEMU Virtual CPU version 2.5+, id 0x663
	cpu3: PAT enabled

	### much other config stuff snipped

	acpicpu0 at cpu0: ACPI CPU
	acpicpu0: id 0, lapic id 0, cap 0x0000, flags 0x00000c21
	vmt0 at cpu0: Unknown
	vmware: open failed, eax=564d5868, ecx=0000001e, edx=00005658
	vmt0: failed to open backdoor RPC channel (TCLO protocol)
	acpicpu1 at cpu1: ACPI CPU
	acpicpu1: id 1, lapic id 1, cap 0x0000, flags 0x00000c21
	acpicpu2 at cpu2: ACPI CPU
	acpicpu2: id 2, lapic id 2, cap 0x0000, flags 0x00000c21
	acpicpu3 at cpu3: ACPI CPU
	acpicpu3: id 3, lapic id 3, cap 0x0000, flags 0x00000c21
	Initializing SSP: 8c28adf057c2aaf6 39b9028b76aa0870 d20cf25d97217579 1ae37818d4f5c757 8a35495040477d50 f4488137e57414de 94a94f41b14c7db9 5c761e3d70b78301 
	cpu1: failed to start
	cpu2: failed to start
	cpu3: failed to start

	### system hangs here


	

	Some on-the-fly analysis on irc seems to conclude that this is
	likely to be a qemu bug, with the secondary CPU(s) stalled in
	cpu_init().

	The same behavior is seen with NetBSD kernels from today's -current,
	today's netbsd-7 branch, and today's netbsd-6-0 branch.
>How-To-Repeat:
	See above
	
>Fix:
	Unknown
	

>Unformatted: