Duplicate free panic installing Beta2 on VMWare

Hi,

I see this when installing 6.0 Beta 2 under VMWare 3.2.1:

 panic: Duplicate free of item 0xc1b0c4a4 from zone 0xc143f000(g_bio)
 
 cpuid = 0
 KDB: enter: panic
 [thread pid 3 tid 100021 ]
 Stopped at      kdb_enter+0x2b: nop
 db> where
 Tracing pid 3 tid 100021 td 0xc1833300
 kdb_enter(c0856274) at kdb_enter+0x2b
 panic(c0870cfb,c1b0c4a4,c143f000,c0850ced,c0870cdf) at panic+0x127
 uma_dbg_free(c143f000,0,c1b0c4a4) at uma_dbg_free+0x110
 uma_zfree_arg(c143f000,c1b0c4a4,0) at uma_zfree_arg+0x66
 g_destroy_bio(c1b0c4a4) at g_destroy_bio+0x13
 g_vfs_done(c1b0c4a4) at g_vfs_done+0x5a
 biodone(c1b0c4a4,ca0bccc4,0,c0850cb0,1e4) at biodone+0x57
 g_io_schedule_up(c1833300) at g_io_schedule_up+0xb5
 g_up_procbody(0,ca0bcd38,0,c05fed08,0) at g_up_procbody+0x5a
 fork_exit(c05fed08,0,ca0bcd38) at fork_exit+0xa0
 fork_trampoline() at fork_trampoline+0x8
 --- trap 0x1, eip = 0, esp = 0xca0bcd6c, ebp = 0 ---

I've added this to PR/84102, the other symptoms are the same as that PR.

Is there a workaround?

Thanks,

Jan Mikkelsen