Re: locking against myself, mbuf was already freed

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

Thanks for the quick reply!

> Isn't there something missing in the stack trace here ?
I don't think so.

> I can't see how m_prepend could be called from ipf_fastroute ...
Maybe the compiler optimized out some function calls?

In fact, the display looks somewhat weird (I'll send you photographs in 
private mail):
<prompt># Kernel RNG "1619 1 1" momobit test FAILURE: 9702 ones
cpnrg 1619 1 1: failed statistical RNG test
panic: mbuf was already freed at nd_resolve,2351
fatal breakpoint trap in suprevisor mode
trap type 1 code 0 rip 0xffffffff8021ffa5 cs 0x8 rflags 0x246 cr2 0x7a47da76300[DISPLAY CUT-OFF]
 ilevel 0x4 rsp 0xffff80013ceab990
curlwp 0xfffffe841de11[VIOLET-ON-WHITE GARBAGE]
Found: sd0a at 0
Looking for 1 in autoconfig
[FOUR-AND-A-HALF MORE LINES OF VIOLET-ON-WHITE GARBAGE]
[GARBAGE]
[GARBAGE]
[GARBAGE]em) at  netbsd:breakpoint+0x05:  leave
db{0}> bt
breakpoint() at netbsd:breakpoint+0x5
vpanic() at netbsd:vpanic+0x15d
snprintf() at netbsd:snprintf
m_prepend() at netbsd:m_prepend
ipf_fastroute() at netbsd:ipf_fastroute+0x2e9
ipf_send_ip() at netbsd:ipf_send_ip+0x13d
ipf_check() at netbsd:ipf_check+0xd1e
pfil_run_hooks() at netbsd:pfil_run_hooks+0x12f
ip6_input() at netbsd:ip6_input+0x1ce
ip6intr() at netbsd:ip6intr+0x87
softint_dispatch() at netbsd:softint_dispatch+0xeb

> Ot maybe it's not m_prepend but m_freem.
No.

> Anyway, I guess the attached patch could fix it.
I don't see anything attached.

> Maybe try to
> #define FASTROUTE_RECURSION
> at the top of fil.c ? It looks like this is needed
I'll give it a try.

Could my other, former panics/lock-ups because by the same issue?