> cinap is right, the bug is in the kernel. we know
> that because it's a lock loop. that can only happen
> if the kernel screws up. also, the address is a kernel
> address (starts with 0xf).
Well, here is an acid dump, I'll inspect it in detail, but I'm hoping
someone will beat me to it (not hard at all, I have to confess):
rumble# acid /sys/src/9/pc/9pccpuf
/sys/src/9/pc/9pccpuf:386 plan 9 boot image
/sys/lib/acid/port
/sys/lib/acid/386
# lock 0xf0057d74 loop key 0xdeaddead pc 0xf01e736a held by pc 0xf01e736a proc
2052
acid: src(0xf01e736a)
/sys/src/9/port/qlock.c:29
24 print("qlock: %#p: nlocks %lud\n", getcallerpc(&q),
up->nlocks.ref);
25
26 if(q->use.key == 0x55555555)
27 panic("qlock: q %#p, key 5*\n", q);
28 lock(&q->use);
>29 rwstats.qlock++;
30 if(!q->locked) {
31 q->locked = 1;
32 unlock(&q->use);
33 return;
34 }
# 61:etherread4 pc f01ef8a0 dbgpc 0 Running (Running) ut 2923 st 0 bss
0 qpc f0148c8a nl 0 nd 0 lpc f0100f6e pri 13
acid: src(0xf01ef8a0)
/sys/src/9/port/taslock.c:96
91 lockstats.glare++;
92 for(;;){
93 lockstats.inglare++;
94 i = 0;
95 while(l->key){
>96 if(conf.nmach < 2 && up && up->edf &&
>(up->edf->flags & Admitted)){
97 /*
98 * Priority inversion, yield on a
uniprocessor; on a
99 * multiprocessor, the other processor
will unlock
100 */
101 print("inversion %#p pc %#lux proc %lud
held by pc %#lux proc %lud\n",
acid: src(0xf0148c8a)
/sys/src/9/ip/tcp.c:2096
2091 if(waserror()){
2092 qunlock(s);
2093 nexterror();
2094 }
2095 qlock(s);
>2096 qunlock(tcp);
2097
2098 /* fix up window */
2099 seg.wnd <<= tcb->rcv.scale;
2100
2101 /* every input packet in puts off the keep alive time out */
acid: src(0xf0100f6e)
/sys/src/9/pc/cga.c:112
107 return;
108 }
109 else
110 lock(&cgascreenlock);
111
>112 while(n-- > 0)
113 cgascreenputc(*s++);
114
115 unlock(&cgascreenlock);
116 }
117
# 2052: exportfs pc f01e7377 dbgpc 94ad Pwrite (Ready) ut 55 st 270 bss
40000 qpc f0145b62 nl 1 nd 0 lpc f01e2c60 pri 10
acid: src(0xf01e7377)
/sys/src/9/port/qlock.c:30
25
26 if(q->use.key == 0x55555555)
27 panic("qlock: q %#p, key 5*\n", q);
28 lock(&q->use);
29 rwstats.qlock++;
>30 if(!q->locked) {
31 q->locked = 1;
32 unlock(&q->use);
33 return;
34 }
35 if(up == 0)
acid: src(0xf0145b62)
/sys/src/9/ip/tcp.c:704
699 tcpgo(Tcppriv *priv, Tcptimer *t)
700 {
701 if(t == nil || t->start == 0)
702 return;
703
>704 qlock(&priv->tl);
705 t->count = t->start;
706 timerstate(priv, t, TcptimerON);
707 qunlock(&priv->tl);
708 }
709
acid: src(0xf01e2c60)
/sys/src/9/port/proc.c:345
340 queueproc(Schedq *rq, Proc *p)
341 {
342 int pri;
343
344 pri = rq - runq;
>345 lock(runq);
346 p->priority = pri;
347 p->rnext = 0;
348 if(rq->tail)
349 rq->tail->rnext = p;
350 else
acid:
