panic while fsck

While fscking from previous panic in ufs2 code on -CURRENT from Sep 2, I 
got this:
panic: ffs_copyonwrite: recursive call
cpuid = 1; lapic.id = 01000000
Debugger("panic")
Stopped at      Debugger+0x55:  xchgl   %ebx,in_Debugger.0
db> trace
Debugger(c03e1565,1000000,c03eebf0,dd78eac8,100) at Debugger+0x55
panic(c03eebf0,c029c4f8,c448a124,0,c03e6165) at panic+0x15f
ffs_copyonwrite(c4256248,ce5d0090,0,c08d43f0,dd78eb78) at 
ffs_copyonwrite+0x42
spec_xstrategy(c4256248,ce5d0090,dd78eb84,c0210668,dd78ebb0) at 
spec_xstrategy+0x112
spec_specstrategy(dd78ebb0,dd78ebcc,c0346830,dd78ebb0,0) at 
spec_specstrategy+0x1b
spec_vnoperate(dd78ebb0,0,c08d43f0,3,ce5d0090) at spec_vnoperate+0x18
ufs_strategy(dd78ebf4,dd78ec2c,c0289dc7,dd78ebf4,1) at ufs_strategy+0xe0
ufs_vnoperate(dd78ebf4,1,c03e4e5c,35a,100100) at ufs_vnoperate+0x18
bwrite(ce5d0090,dd78ec78,c03392f9,ce5d0090,0) at bwrite+0x427
bawrite(ce5d0090,0,c03f04cd,e1,367) at bawrite+0x1c
ffs_fsync(dd78eca4,0,c03e6509,ad8,0) at ffs_fsync+0x2a9
fsync(c42374c0,dd78ed10,c03f6ad5,3eb,1) at fsync+0x151
syscall(2f,2f,2f,17a2f000,97d0a60) at syscall+0x253
Xint0x80_syscall() at Xint0x80_syscall+0x1d
--- syscall (95, FreeBSD ELF32, fsync), eip = 0x2861b01f, esp = 
0xbfa87eb4, ebp = 0xbfa87ed0 ---
db>

Pete