kern/45876: panic: kernel diagnostic assertion "sb->sb_mbtail == NULL" failed

[Hauke Fath <hauke%Espresso.Rhein-Neckar.DE@localhost>]

>Number:         45876
>Category:       kern
>Synopsis:       panic: kernel diagnostic assertion "sb->sb_mbtail == NULL" 
>failed
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jan 26 20:30:00 +0000 2012
>Originator:     Hauke Fath
>Release:        NetBSD 5.1_STABLE
>Organization:
Falling Raindrops
>Environment:
        
        
System: NetBSD pizza.causeuse.org 5.1_STABLE NetBSD 5.1_STABLE (HENKELMANN) #2: 
Mon Jan 23 22:41:08 CET 2012 
hauke%pizza.causeuse.org@localhost:/var/obj/netbsd-builds/5/macppc/sys/arch/macppc/compile/HENKELMANN
 macppc
Architecture: powerpc
Machine: macppc
>Description:

[...]
Jan 26 19:39:44 pizza ntpd[18426]: time reset +2.364882 s
Jan 26 19:44:46 pizza ntpd[18426]: synchronized to 192.53.103.108, stratum 1
Jan 26 19:55:29 pizza ntpd[18426]: time reset +2.477143 s
Jan 26 20:00:23 pizza ntpd[18426]: synchronized to 78.46.70.42, stratum 2
Jan 26 20:03:47 pizza syslogd: restart
Jan 26 20:03:47 pizza /netbsd: pid 679 (squid), uid 39: exited on signal 4 
(core dumped)
Jan 26 20:03:47 pizza /netbsd: panic: kernel diagnostic assertion 
"sb->sb_mbtail == NULL" failed: file 
"/export/netbsd-5/sys/kern/uipc_socket2.c", line 1221
Jan 26 20:03:47 pizza /netbsd: Begin traceback...
Jan 26 20:03:47 pizza /netbsd: 0xd420cb90: at __kernassert+0x4c
Jan 26 20:03:47 pizza /netbsd: 0xd420cba0: at sbflush+0xf4
Jan 26 20:03:47 pizza /netbsd: 0xd420cbc0: at tcp_disconnect+0x58
Jan 26 20:03:47 pizza /netbsd: 0xd420cbe0: at tcp_usrreq+0x1b8
Jan 26 20:03:47 pizza /netbsd: 0xd420cc20: at tcp_usrreq_wrapper+0xc
Jan 26 20:03:47 pizza /netbsd: 0xd420cc30: at sodisconnect+0x80
Jan 26 20:03:47 pizza /netbsd: 0xd420cc50: at soclose+0x234
Jan 26 20:03:47 pizza /netbsd: 0xd420cc80: at soo_close+0x24
Jan 26 20:03:47 pizza /netbsd: 0xd420cca0: at closef+0xa0
Jan 26 20:03:47 pizza /netbsd: 0xd420cce0: at fd_close+0x14c
Jan 26 20:03:47 pizza /netbsd: 0xd420cd30: at fd_free+0xe4
Jan 26 20:03:47 pizza /netbsd: 0xd420cd80: at exit1+0x12c
Jan 26 20:03:47 pizza /netbsd: 0xd420ce00: at sigexit+0x1c0
Jan 26 20:03:47 pizza /netbsd: 0xd420ce30: at postsig+0x130
Jan 26 20:03:47 pizza /netbsd: 0xd420ce90: at lwp_userret+0x178
Jan 26 20:03:47 pizza /netbsd: 0xd420ceb0: at trap+0x430
Jan 26 20:03:47 pizza /netbsd: 0xd420cf40: user PGM trap by 0x190cc80: 
srr1=0x8f032
Jan 26 20:03:47 pizza /netbsd: r1=0xffffda80 cr=0x84004042 xer=0 ctr=0x19169e4
Jan 26 20:03:47 pizza /netbsd: End traceback...
Jan 26 20:03:47 pizza /netbsd: dumpsys: TBD
Jan 26 20:03:47 pizza /netbsd: sd0: cache synchronization failed
Jan 26 20:03:47 pizza /netbsd: rebooting
        
>How-To-Repeat:

        Run squid on netbsd-5 (macppc here), I guess? I see the
        occasional crash from this machine (a Yosemite G3/400),
        usually network related.

>Fix:
        No idea.

>Unformatted: