Panic in pipe_write from syslogd in 12.2?

I just noticed that a couple of my 12.2-RELEASE-p4 running servers have… 8263, 14474 and 3831 defunct subprocesses from syslogd and also seems to have stopped writing to the log files… When I tried to kill syslogd on a fourth server (with some X000 defunct processes) the machine panic’ed and rebooted.

I seem to have a vague memory of this being a known bug/someone saw something similar or perhaps even solved in later patch releases? But my google-fu seems to be failing me today. Anyone else remember?

(The one that panic’ed is now running -p10 instead which they should have done a long time ago but…)


I reported it on the FreeBSD bugzilla:
  https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=259084 <https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=259084>


Output from one that still is running:
# egrep syslogd /var/log/sys/15:10/procstat-kk-a.log
 9212 101640 syslogd             -                   mi_switch+0xd4 sleepq_catch_signals+0x403 sleepq_wait_sig+0xf _sleep+0x1de pipe_write+0x583 dofilewrite+0xb0 sys_write+0xc0 amd64_syscall+0x387 fast_syscall_common+0xf8

Output from the one that panic’ed:
Fatal trap 12: page fault while in kernel mode
cpuid = 20; apic id = 14
fault virtual address	= 0x410
fault code		= supervisor read data, page not present
instruction pointer	= 0x20:0xffffffff80b9f55c
stack pointer	        = 0x28:0xfffffe14debc6710
frame pointer	        = 0x28:0xfffffe14debc6790
code segment		= base r <https://svnweb.freebsd.org/changeset/base/>x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 9277 (sshd)
trap number		= 12
panic: page fault
cpuid = 20
time = 1633990484
KDB: stack backtrace:
#0 0xffffffff80c0ad75 at kdb_backtrace+0x65
#1 0xffffffff80bbf02b at vpanic+0x17b
#2 0xffffffff80bbeea3 at panic+0x43
#3 0xffffffff8108e911 at trap_fatal+0x391
#4 0xffffffff8108e96f at trap_pfault+0x4f
#5 0xffffffff8108dfb6 at trap+0x286
#6 0xffffffff81066c28 at calltrap+0x8
#7 0xffffffff80c6365f at unp_pcb_owned_lock2_slowpath+0x12f
#8 0xffffffff80c61e0f at uipc_send+0x139f
#9 0xffffffff80c55b7a at sosend_generic+0x4ca
#10 0xffffffff80c55f90 at sosend+0x50
#11 0xffffffff80c5cc55 at kern_sendit+0x225
#12 0xffffffff80c5cfcc at sendit+0x19c
#13 0xffffffff80c5ce1d at sys_sendto+0x4d
#14 0xffffffff8108f4c7 at amd64_syscall+0x387
#15 0xffffffff8106754e at fast_syscall_common+0xf8
Uptime: 212d21h35m47s

- Peter