panic: sbdrop

[Paulius Bulotas]

Hello,

we have two Sun Fire X4100 running quite recent current:
FreeBSD 7.0-CURRENT #0: Fri Feb 23 21:12:46 EET 2007
root at anti:/usr/obj/usr/src/sys/GENERIC  amd64

and they both panic once a day or two with:

panic: sbdrop
cpuid = 1
KDB: enter: panic
[thread pid 68163 tid 100266 ]
Stopped at      kdb_enter+0x2f: nop
db> bt
Tracing pid 68163 tid 100266 td 0xffffff00abdb47b0
kdb_enter() at kdb_enter+0x2f
panic() at panic+0x225
sbdrop_internal() at sbdrop_internal+0x1bd
sbflush_internal() at sbflush_internal+0x3c
sbrelease_internal() at sbrelease_internal+0x1c
sofree() at sofree+0x1ea
soclose() at soclose+0x249
soo_close() at soo_close+0x3f
fdrop_locked() at fdrop_locked+0xc8
closef() at closef+0x324
kern_close() at kern_close+0x15d
syscall() at syscall+0x1ef
Xfast_syscall() at Xfast_syscall+0xab
--- syscall (6, FreeBSD ELF64, close), rip = 0x800c7a3cc, rsp = 0x7fffffffec48, rbp = 0 ---

it seems, there is open PR with similar panic, but difference backtrace:
http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/96042

any ideas?

TIA
Paulius