kern/73675: atapicam causes interrupt storm

[Nejc Skoberne]

>Number:         73675
>Category:       kern
>Synopsis:       atapicam causes interrupt storm
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Nov 08 18:30:27 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Nejc Skoberne
>Release:        5.3
>Organization:
>Environment:
FreeBSD Svarun.arnes.si 5.3-RELEASE FreeBSD 5.3-RELEASE #0: Fri Nov  5 04:19:18 UTC 2004     root at harlow.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

>Description:
I happen to have ASUS P4C800-E motherboard with Promise PDC20378 SATA150 controller. When compiling kernel with "driver atapicam" enabled and booting it, there is an error when booting kernel: 

Interrupt storm detected on "irq18: atapci1 em0": throttling interrupt source

The error is fatal (kernel doesn't boot in full).

Conflicting hardware:

atapci1: <Intel ICH5 UDMA100 controller> port 0xef90-0xef9f,0xefa8-0xefab,0xefa0-0xefa7,0xefac-0xefaf,0xefe0-0xefe7 irq 18 at device 31.1 on pci0

em0: <Intel(R) PRO/1000 Network Connection, Version - 1.7.35> port 0xcf80-0xcf9f mem 0xfe5e0000-0xfe5fffff irq 18 at device 1.0 on pci2
em0: Ethernet address: 00:11:2f:c9:a7:9a
em0:  Speed:N/A  Duplex:N/A

>How-To-Repeat:
Have ASUS P4C800-E motherboard with Promise RAID enabled and try to compile GENERIC kernel with "driver atapicam" added. Kernel panics.
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: