Process stuck in getblk

With GENERIC HEAD from Mar 18 15:56 UTC I ran into these two
problems where a user process seems to be waiting on a lock,
that appears to be owned by non-existent thread.

5123 [SLPQ getblk 0xc665717c][SLP] mkdir

sleepq_switch(c665717c,cf4698c8,c061bcd5,...) at sleepq_switch+0xe0
sleepq_wait(c665717c,0,0,2010020,600) at sleepq_wait+0x30
msleep(c665717c,c09118dc,50,c083af8f,0) at msleep+0x311
acquire(cf469920,2010020,600,c1b2b000,0) at acquire+0xba
debuglockmgr(c665717c,2090022,c1e7d5a0,...) at debuglockmgr+0x406
getblk(c1e7d500,0,0,800,0) at getblk+0x15a
breadn(c1e7d500,0,0,800,0) at breadn+0x58
bread(c1e7d500,0,0,800,0) at bread+0x20
ffs_blkatoff(c1e7d500,0,0,0,cf469a58) at ffs_blkatoff+0x9e
ufs_lookup(cf469b18) at ufs_lookup+0x326
VOP_CACHEDLOOKUP_APV(c08cf140,cf469b18) at VOP_CACHEDLOOKUP_APV+0x7e
vfs_cache_lookup(cf469b9c) at vfs_cache_lookup+0xd2
VOP_LOOKUP_APV(c08cf140,cf469b9c) at VOP_LOOKUP_APV+0x7e
lookup(cf469c7c,c0918d80,0,c1b2b000,69f) at lookup+0x362
namei(cf469c7c) at namei+0x34a
kern_rmdir(c1b2b000,bfbc97d0,0,cf469d40,c07cc3a3) at kern_rmdir+0x3a
rmdir(c1b2b000,cf469d14,1,25,292) at rmdir+0x12
syscall(2804002f,bfbf002f,bfb8002f,2804f24c,bfbfeb00) at syscall+0x213

(kgdb) p (*(struct lock *)0xc665717c)->lk_lockholder->td_state
$2 = TDS_INACTIVE

http://www.holm.cc/stress/log/cons122.html
http://www.holm.cc/stress/log/cons123.html
-- 
Peter Holm