From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Sun, 29 Jun 2008 17:32:51 -0700
From: Anthony Martin <ality@pbrane.org>
To: 9fans@9fans.net
Message-ID: <20080630003250.GA8819@dinah>
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Subject: [9fans] 9vx fork problem
Topicbox-Message-UUID: cbf7e340-ead3-11e9-9d60-3106f5b1d025

On 9vx, iostats suicides:

  term% iostats echo
  iostats 128: suicide: sys: trap: page fault pc=0x0000b21c

Apparently, after a fork, a child retains it's parent's
pid in _tos->pid. It isn't updated until the next syscall
finishes with kexit.

This is a problem if the child's first function call is
malloc. When malloc locks it's pool, it stores the pid
from _tos in a private area. After the kernel returns from
the brk, _tos->pid has been corrected by the call to kexit.
Punlock then fails because the pids don't match.

I'm not sure of the best way to go about fixing this.

     Anthony