kern/131290: [hang]: How to completely freeze FreeBSD 7.1 under a non-privileged user

[Mark Linimon]

The following reply was made to PR kern/131290; it has been noted by GNATS.

From: linimon at lonesome.com (Mark Linimon)
To: bug-followup at FreeBSD.org
Cc:  
Subject: Re: kern/131290: [hang]: How to completely freeze FreeBSD 7.1 under a non-privileged user
Date: Sun, 8 Feb 2009 19:09:31 -0600

 ----- Forwarded message from Mikolaj Golub <to.my.trociny at gmail.com> -----
 
 Some more data from the debugger session:
 
 (kgdb) frame 12
 #12 0xc07d4b3b in doselwakeup (sip=0xc4f0c1f0, pri=88) at /usr/src/sys/kern/sys_generic.c:1138
 1138            TAILQ_REMOVE(&td->td_selq, sip, si_thrlist);
 (kgdb) p *sip      
 $2 = {si_thrlist = {tqe_next = 0xc5137d50, tqe_prev = 0xc4682ce0}, si_thread = 0xc4682cc0, si_note = {
     kl_list = {slh_first = 0x0}, kl_lock = 0xc0770070 <knlist_mtx_lock>, 
     kl_unlock = 0xc07700a0 <knlist_mtx_unlock>, kl_locked = 0xc0773640 <knlist_mtx_locked>, 
     kl_lockarg = 0xc4f0c2fc}, si_flags = 0}
 (kgdb) p *sip->si_thrlist.tqe_next
 $6 = {si_thrlist = {tqe_next = 0x0, tqe_prev = 0x0}, si_thread = 0x0, si_note = {kl_list = {
       slh_first = 0x0}, kl_lock = 0xc0770070 <knlist_mtx_lock>, 
     kl_unlock = 0xc07700a0 <knlist_mtx_unlock>, kl_locked = 0xc0773640 <knlist_mtx_locked>, 
     kl_lockarg = 0xc5137d74}, si_flags = 0}
 (kgdb) p **sip->si_thrlist.tqe_prev
 $12 = {si_thrlist = {tqe_next = 0xc5137d50, tqe_prev = 0xc4682ce0}, si_thread = 0xc4682cc0, si_note = {
     kl_list = {slh_first = 0x0}, kl_lock = 0xc0770070 <knlist_mtx_lock>, 
     kl_unlock = 0xc07700a0 <knlist_mtx_unlock>, kl_locked = 0xc0773640 <knlist_mtx_locked>, 
     kl_lockarg = 0xc4f0c2fc}, si_flags = 0}
 
 Also, I tried FreeBSD 8.0-CURRENT kernel (with 7STABLE userland). When I run
 /usr/local/etc/rc.d/ejabberd stop it panics too with the same message.
 
   Architecture: i386
   Architecture Version: 1
   Dump Length: 187904B (0 MB)
   Blocksize: 512
   Dumptime: Sun Feb  8 23:47:58 2009
   Hostname: zhuzha.ua1
   Magic: FreeBSD Text Dump
   Version String: FreeBSD 8.0-CURRENT #0 r188297: Sun Feb  8 22:39:36 EET 2009
     root at zhuzha.ua1:/home/golub/freebsd/build/obj/home/golub/freebsd/src/sys/DEBUG
   Panic String: Bad link elm 0xc5005a80 prev->next != elm
   Dump Parity: 1084020072
   Bounds: 2
   Dump Status: good
 
 -- 
 Mikolaj Golub
 
 ----- End forwarded message -----