kern/41095: ahcisata won't dump

[kardel%pip.acrys.com@localhost]

>Number:         41095
>Category:       kern
>Synopsis:       dumps via ahcisata fail
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Mar 29 17:25:00 +0000 2009
>Originator:     Frank Kardel
>Release:        NetBSD 5.99.8
>Organization:
        
>Environment:
System: NetBSD pip.kardel.name 5.99.8 NetBSD 5.99.8 (PIP) #28: Sun Mar 22 
16:45:44 MET 2009 
kardel%pip.kardel.name@localhost:/fs/raid1a/src/NetBSD/tc-merge/src/obj.i386/sys/arch/i386/compile/PIP
 i386
Architecture: i386
Machine: i386
>Description:
        On panic ahcisata failt to dump, well it spits out an error message:
        "ahcisata1 port 0 device connected, but communication not established"
        and then happily show the dump countdoen (hao much memors is still to 
be dumped)
        with a nice "success" at the end. After that dump fails
        with an error message as the FLUSH of the disk wouldn't work because of 
timeout.

        It looks like there is not much error checking goinf on and the device 
has
        not properly been initialized.

        ahcisata1 at pci0 dev 31 function 2: vendor 0x8086 product 0x2922
        ahcisata1: interrupting at ioapic0 pin 19
        ahcisata1: AHCI revision 1.2, 6 ports, 32 command slots, features 
0xe722e0c0
        atabus4 at ahcisata1 channel 0
        atabus5 at ahcisata1 channel 1
        atabus6 at ahcisata1 channel 2
        atabus7 at ahcisata1 channel 3
        atabus8 at ahcisata1 channel 4
        atabus9 at ahcisata1 channel 5
        ahcisata1 port 5: device present, speed: 1.5Gb/s
        ahcisata1 port 1: device present, speed: 1.5Gb/s
        ahcisata1 port 0: device present, speed: 1.5Gb/s
        ahcisata1 port 4: device present, speed: 1.5Gb/s
        ...
        wd2 at atabus4 drive 0: <WDC WD1500ADFD-00NLR5>
        wd2: drive supports 16-sector PIO transfers, LBA48 addressing
        wd2: 139 GB, 290721 cyl, 16 head, 63 sec, 512 bytes/sect x 293046768 
sectors
        wd2: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
        wd2(ahcisata1:0:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 6 
(Ultra/133) (using DMA)

>How-To-Repeat:
        Attempt to get a crash dump via ahcisata1 port 0 (000:31:2: Intel 
82801I AHCI SATA Controller w/ 6 ports (SATA mass storage, interface 0x01, 
revision 0x02))
        Watch the nice dump simulation. Nothing reaches the disk however.
>Fix: