kern/53228: recent acpica import causes boot-time failures

[paul%whooppee.com@localhost]

>Number:         53228
>Category:       kern
>Synopsis:       recent acpica import causes boot-time failures
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Apr 29 07:15:00 +0000 2018
>Originator:     Paul Goyette
>Release:        NetBSD 8.99.14
>Organization:
+------------------+--------------------------+----------------------------+
| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:          |
| (Retired)        | FA29 0E3B 35AF E8AE 6651 | paul at whooppee dot com   |
| Kernel Developer | 0786 F758 55DE 53BA 7731 | pgoyette at netbsd dot org |
+------------------+--------------------------+----------------------------+
>Environment:
	
	
System: NetBSD speedy.whooppee.com 8.99.14 NetBSD 8.99.14 (SPEEDY 2018-03-20 11:25:00 UTC) #0: Wed Mar 21 10:38:29 UTC 2018 paul%speedy.whooppee.com@localhost:/build/netbsd-local/obj/amd64/sys/arch/amd64/compile/SPEEDY amd64
Architecture: x86_64
Machine: amd64
>Description:
After the recent (2018-04-07 14:00-1600 UTC) import/update of acpica,
my ASUS X99-E motherboard fails to boot.  It would appear that some
change within acpica has changed the way PCI interrupt routing is
handled.  This same hardware works fine with previous acpica version.

Specific symptoms are the appearance of the following warning messages
indicating that interrupt routing is being mis-handled:

	...
	acpi0 at mainbus0: Intel ACPICA 20180313
	acpi0: X/RSDT: OemId <ALASKA,  A M I ,01072009>, AslId <AMI ,00010013>
	mpacpi: PCI bus 255 int routing already done!
	mpacpi: PCI bus 255 int routing already done!
	mpacpi: PCI bus 255 int routing already done!
	mpacpi: PCI bus 0 int routing already done!
	mpacpi: PCI bus 2 int routing already done!
	mpacpi: PCI bus 3 int routing already done!
	mpacpi: PCI bus 1 int routing already done!
	mpacpi: PCI bus 0 int routing already done!
	mpacpi: PCI bus 2 int routing already done!
	mpacpi: PCI bus 3 int routing already done!
	mpacpi: PCI bus 1 int routing already done!
	mpacpi: PCI bus 0 int routing already done!
	mpacpi: PCI bus 2 int routing already done!
	mpacpi: PCI bus 3 int routing already done!
	mpacpi: PCI bus 1 int routing already done!
	acpi0: MCFG: segment 0, bus 0-255, address 0x00000000e0000000
	acpi0: SCI interrupting at int 9
	...

Later in the boot, we see that both my ahcisata-attached wd disks fail
to complete their IDENTIFY command, and the ehci USB controller(s) are
timing out - both are suggestive of missed interrupts.

	...
	ahcisata0 port 0: device present, speed: 6.0Gb/s
	ahcisata0 port 1: device present, speed: 6.0Gb/s
	wd0 at atabus0 drive 0
	wd0: <WDC WD5000AZLX-00K2TA0>
	wd0: drive supports 16-sector PIO transfers, LBA48 addressing
	wd0: 465 GB, 969021 cyl, 16 head, 63 sec, 512 bytes/sect x 976773168 sectors
	wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133), NCQ (32 tags) w/PRIO
	wd0(ahcisata0:0:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133) (using DMA), NCQ (31 tags) w/PRIO
	wd1 at atabus1 drive 0
	wd1: <WDC WD5000AZLX-00CL5A0>
	wd1: drive supports 16-sector PIO transfers, LBA48 addressing
	wd1: 465 GB, 969021 cyl, 16 head, 63 sec, 512 bytes/sect x 976773168 sectors
	wd1: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133), NCQ (3 2 tags) w/PRIO
	wd1(ahcisata0:1:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133) (using DMA), NCQ (31 tags) w/PRIO
	...
	wd0: IDENTIFY failed
	wd0: fixing 0 sector size
	wd0: secperunit and ncylinders are zero
	wd0(ahcisata0:0:0): using PIO mode 0
	wd1 at atabus1 drive 0
	ehci_sync_hc: timed out
	ehci_sync_hc: timed out
	wd1: IDENTIFY failed
	wd1: fixing 0 sector size
	wd1: secperunit and ncylinders are zero
	wd1(ahcisata0:1:0): using PIO mode 0
	ehci_sync_hc: timed out
	ehci_sync_hc: timed out
	ehci_sync_hc: timed out
	...

After this, the boot process prompts for root device (since neither of the
disks found were succcessfully IDENTIFYd).  Pressing any key on the USB-
attached keyboard results in a panic and reboot.

(I will post dmesg from both successful and failed boots as follow-ups
to this PR, once the PR is assigned.)
	
>How-To-Repeat:
See above.  
	
>Fix:
Unknown.  However, please see discussion in PR kern/43570 for some
additional background.
	

>Unformatted: