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Subject: Re: [linux-dvb] RFC - Flexcop Streaming watchdog (VDSB)
From: Andy Walls <awalls@radix.net>
To: Patrick Boettcher <patrick.boettcher@desy.de>
Cc: BOUWSMA Barry <freebeer.bouwsma@gmail.com>, lexW <HondaNSX@gmx.de>,
	Linux Media Mailing List <linux-media@vger.kernel.org>
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Date: Sat, 17 Jan 2009 08:18:56 -0500
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Patrick,

Please ignore my comment prior in this thread about using
spin_lock_irq() vs. spin_lock_irqsave().  Between lack of sleep and
trying to install Fedora 10 and recover my data on what now appears to
be a failing motherboard/cpu, I made an error.  I realized spinlock
functions should always disable local IRQs (*smacks forehead*).

What one has to take care with is unconditionally re-enabling local IRQs
with spin_unlock_irq().  One would think that a work handler is known to
be called in a non-irq context.  So, at the risk of being wrong again,
using spin_unlock_irq() should be OK, if spin_lock_irq() is allowed by
the kernel in a work handler context (which your experimentation
indicates that it is not).

Regards,
Andy