Bug 116620

Summary: [hang] ifconfig spins when creating carp(4) device on amd64/SMP
Product: Base System Reporter: Chris Chen <muffaleta>
Component: amd64Assignee: freebsd-amd64 (Nobody) <amd64>
Status: Closed FIXED    
Severity: Affects Only Me    
Priority: Normal    
Version: Unspecified   
Hardware: Any   
OS: Any   

Description Chris Chen 2007-09-25 00:50:01 UTC 
After startup, run ifconfig carp0 create.

The process will spin. It is impossible to kill the spinning ifconfig process. The rest of the system remains operational, however, so you can reboot it.

Here are the last lines of a ktrace of ifconfig carp0 create:

  944 ifconfig CALL  modstat(0x10a,0x7fffffffe280)
  944 ifconfig RET   modstat 0
  944 ifconfig CALL  modfnext(0x10a)
  944 ifconfig RET   modfnext 267/0x10b
  944 ifconfig CALL  modstat(0x10b,0x7fffffffe280)
  944 ifconfig RET   modstat 0
  944 ifconfig CALL  socket(0x2,0x2,0)
  944 ifconfig RET   socket 3
  944 ifconfig CALL  ioctl(0x3,SIOCIFCREATE,0x514ce0)

After this point, the process take up 100% cpu, and just spins.

How-To-Repeat: Run ifconfig carp0 create.
Comment 1 Andriy Gapon freebsd_committer freebsd_triage 2010-12-05 10:09:19 UTC 
Is this still an issue with the latest versions of FreeBSD?

-- 
Andriy Gapon
Comment 2 Jaakko Heinonen freebsd_committer freebsd_triage 2011-09-24 08:43:07 UTC 
State Changed
From-To: open->feedback

Note that submitter has been asked for feedback.
Comment 3 Jaakko Heinonen freebsd_committer freebsd_triage 2011-11-11 19:13:03 UTC 
State Changed
From-To: feedback->closed

Feedback timeout.