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Date: Tue, 23 Apr 2013 10:44:56 -0700
Message-ID: <CALCNsJQAA+9k6jq1bQJyavOLmd7Xc6BqgoLBUJfAQqecuOeENw@mail.gmail.com>
Subject: vmspace_fork()
From: Vijay Singh <vijju.singh@gmail.com>
To: hackers@freebsd.org
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Hackers, what does hitting the following assert in vmspace_fork() imply?

 3101 <http://fxr.watson.org/fxr/source/vm/vm_map.c#L3101>
new_map = &vm2 <http://fxr.watson.org/fxr/ident?im=3;i=vm2>->vm_map
<http://fxr.watson.org/fxr/ident?im=3;i=vm_map>;
 3102 <http://fxr.watson.org/fxr/source/vm/vm_map.c#L3102>
locked <http://fxr.watson.org/fxr/ident?im=3;i=locked> =
vm_map_trylock <http://fxr.watson.org/fxr/ident?im=3;i=vm_map_trylock>(new_map);
*/* trylock to silence WITNESS */*
 3103 <http://fxr.watson.org/fxr/source/vm/vm_map.c#L3103>
KASSERT <http://fxr.watson.org/fxr/ident?im=3;i=KASSERT>(locked
<http://fxr.watson.org/fxr/ident?im=3;i=locked>, (*"vmspace_fork: lock
failed"*));

I am hitting the assert in line 3103 and it seems like the assumption
is that the trylock will

always get the lock?

-vijay