rem: printf("block %ld isn't coming un-busy (ce @ 0x%lx)\n", ce->block_num, (ulong)ce);
add: printf("block %Ld isn't coming un-busy (ce @ %p)\n", ce->block_num, ce);
context: block_lookup(int dev, fs_off_t bnum){    int        count = 0;    cache_ent *ce;    while (1) {        ce = hash_lookup(&bc.ht, dev, bnum);        if (ce == NULL)            return NULL;        if ((ce->flags & CE_BUSY) == 0) /* it's ok, break out and return it */            break;        /* else, it's busy and we need to retry our lookup */        UNLOCK(bc.lock);        snooze(5000);        if (count++ == 5000) {  /* then a lot of time has elapsed */            printf("block %ld isn't coming un-busy (ce @ 0x%lx)\n",                   ce->block_num, (ulong)ce);        }        LOCK(bc.lock);    }    if (ce->flags & CE_BUSY)        panic("block lookup: returning a busy block @ 0x%lx?!?\n",(ulong)ce);    return ce;}