kern/55387: kernel diagnostic assertion "c->c_cpu->cc_lwp == curlwp || c->c_cpu->cc_active != c" failed

[Thomas Klausner <wiz%NetBSD.org@localhost>]

>Number:         55387
>Category:       kern
>Synopsis:       kernel diagnostic assertion "c->c_cpu->cc_lwp == curlwp || c->c_cpu->cc_active != c" failed
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Jun 15 08:15:00 +0000 2020
>Originator:     Thomas Klausner
>Release:        NetBSD 9.99.63
>Organization:
Curiosity is the very basis of education and if you tell me that
curiosity killed the cat, I say only that the cat died nobly.
- Arnold Edinborough
>Environment:
	
	
System: NetBSD yt.nih.at 9.99.63 NetBSD 9.99.63
Architecture: x86_64
Machine: amd64
>Description:

With a 9.99.63/amd64 kernel from May 19 I saw a panic:

Jun  7 01:01:01 yt savecore: reboot after panic: [ 396809.5836453] panic: kernel diagnostic assertion "c->c_cpu->cc_lwp == curlwp || c->c_cpu->cc_active != c" failed: file "/usr/src/sys/kern/kern_timeout.c", line 322 running callout 0xffff835adaa87658: c_func (0xffffffff809f459f) c_flags (0x100) destroyed from 0xffffffff809f264b
Jun  7 01:01:01 yt savecore: writing compressed core to /var/crash/netbsd.12.core.gz

(gdb) bt
#0  0xffffffff80226865 in cpu_reboot (howto=howto@entry=260, bootstr=bootstr@entry=0x0) at /usr/src/sys/arch/amd64/amd64/machdep.c:713
#1  0xffffffff80cd387f in kern_reboot (howto=howto@entry=260, bootstr=bootstr@entry=0x0) at /usr/src/sys/kern/kern_reboot.c:73
#2  0xffffffff80d1285e in vpanic (
    fmt=0xffffffff8143e908 "kernel %sassertion \"%s\" failed: file \"%s\", line %d running callout %p: c_func (%p) c_flags (%#x) destroyed from %p", 
    ap=ap@entry=0xffff850916323c88) at /usr/src/sys/kern/subr_prf.c:290
#3  0xffffffff80e834b6 in kern_assert (
    fmt=fmt@entry=0xffffffff8143e908 "kernel %sassertion \"%s\" failed: file \"%s\", line %d running callout %p: c_func (%p) c_flags (%#x) destroyed from %p")
    at /usr/src/sys/lib/libkern/kern_assert.c:51
#4  0xffffffff80cf1708 in callout_destroy (cs=cs@entry=0xffff835adaa87658) at /usr/src/sys/kern/kern_timeout.c:323
#5  0xffffffff809f264b in tcp_close (tp=tp@entry=0xffff835adaa874c8) at /usr/src/sys/netinet/tcp_subr.c:1227
#6  0xffffffff809ecb83 in tcp_input (m=0xffff83415e784b00, off=20, proto=<optimized out>) at /usr/src/sys/netinet/tcp_input.c:2396
#7  0xffffffff809dde5f in ip_input (m=<optimized out>) at /usr/src/sys/netinet/ip_input.c:816
#8  ipintr (arg=<optimized out>) at /usr/src/sys/netinet/ip_input.c:402
#9  0xffffffff80ce18ae in softint_execute (s=4, l=0xffff835d46efb480) at /usr/src/sys/kern/kern_softint.c:565
#10 softint_dispatch (pinned=<optimized out>, s=4) at /usr/src/sys/kern/kern_softint.c:814
#11 0xffffffff80220eef in Xsoftintr ()
(gdb)

There was no particular user activity at the time. My usual network usage mix
is NFS, some bittorrent, some sftp, some ssh, but this was at a time when I
wasn't doing anything myself.

I will keep the kernel dump around for a while in case of interest in
more details from it.
>How-To-Repeat:
Happened randomly.
>Fix:
Please.

>Unformatted: