Bug 131793

  >Submitter-Id:  current-users
  >Originator:    Colin Faber
  >Organization:  n/a
  >Confidential:  no
  >Synopsis:      Introducing new USB or eSATA disks results in atapci1+ 
 irq storm until reboot
  >Severity:      serious
  >Priority:      high
  >Category:      kern
  >Class:         sw-bug
  >Release:       FreeBSD 7.1-RELEASE-p2 amd64
  >Environment:
 System: FreeBSD hal.fpsn 7.1-RELEASE-p2 FreeBSD 7.1-RELEASE-p2 #2: Sun 
 Feb 15 12:21:19 MST 2009 cfaber@hal.fpsn:/usr/obj/usr/src/sys/HAL amd64
 
 
  >Description:
         It appears that when plugging in any USB, or eSATA disk drive, 
 atapci1+ gets stuck
         in a massive irq storm, running about 13k irqs a second. This 
 results in about 90%
         interrupt load on the system and makes everything unstable and slow.
 
         Note - this load appears even with ZERO activity on the device 
 in question and little
         or no geom activity.
 
         Also Note - this machine is running two geom_raid5 array's made 
 of geom labeled providers
 
  >How-To-Repeat:
         Build amd64 7.1-RELENG-p2 and attach any umass disk or eSata disk
  >Fix:
 
         Thus far, the only solution I've been able to find is to reboot 
 the kernel. Disconnecting the
         disk which caused the storm does not seem to cause it to slow or 
 stop. Only rebooting does.