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Date: Wed, 12 Jun 2013 20:01:15 +0200
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: current@freebsd.org
Subject: copyin()/copyout() constraints ?
Message-ID: <20130612180115.GA27892@onelab2.iet.unipi.it>
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hi,
is it possible to run copyin() or copyout() in one of these cases:
1. while holding a spinlock
2. while holding a regular mutex/lock
3. while holding a read lock (on an RWLOCK or RMLOCK)
4. while holding a write lock (on an RWLOCK or RMLOCK)

I suspect #1 is forbidden, but am a bit unclear for the
other cases.

thanks
luigi