Re: New panic in main-n253273-a52d8d4a6c6:

From: Hans Petter Selasky <hps_at_selasky.org>
Date: Mon, 21 Feb 2022 07:48:27 UTC 
On 2/20/22 21:53, Michael Jung wrote:
> Hi!
> 
> The box was quite busy at the time.  The only odd thing I am aware of and which I do
> not think is related is I have not been able to expand one of my zpool's.  ZFS sees my
> added draid2:2d:10c:0s vdev but I can't seem to force zpool's expansion - my bet this
> is somehow related to the mirrored special device in the pool even though autoexpand
> is set to 'on' for the pool.
> 
> Not asking anyone to solve this, I plan on putting together a "how to reproduce" and
> post to freebsd-fs@ but wanted to note this oddity.
> 
> --mikej
> 
> This is a unmodified GENERIC kernel.
> 
> 
> Unread portion of the kernel message buffer:
> panic: refcount 0xfffff801cc119284 wraparound
> cpuid = 7
> time = 1645382575
> KDB: stack backtrace:
> db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0119a83c80
> vpanic() at vpanic+0x17f/frame 0xfffffe0119a83cd0
> panic() at panic+0x43/frame 0xfffffe0119a83d30
> fdclose() at fdclose/frame 0xfffffe0119a83dc0
> closefp_impl() at closefp_impl+0x77/frame 0xfffffe0119a83e00
> amd64_syscall() at amd64_syscall+0x12e/frame 0xfffffe0119a83f30
> fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0119a83f30
> --- syscall (6, FreeBSD ELF64, sys_close), rip = 0x3309a531b62a, rsp = 0x3309a2802bc8, rbp = 0x3309a2803000 ---
> KDB: enter: panic
> 

This may be a refcount leak. Are you able to dump "fdp" at:

#16 0xffffffff80bad587 in closefp_impl (fdp=0xfffffe012b7c0430, fd=4,
     fp=0xfffff801cc119280, td=0xfffffe00df8d0560, audit=true)
     at /usr/src/sys/kern/kern_descrip.c:1300

frame 16
print /x *fdp

--HPS