Re: [PATCH] synclink_gt add compat_ioctl

From: Arnd Bergmann
Date: Wed May 02 2007 - 18:48:26 EST


On Thursday 03 May 2007, Paul Fulghum wrote:
> >> +
> >> +    spin_lock_irqsave(&info->lock, flags);
> >
> > no need for _irqsave, just use spin_{,un}lock_irq() when you know that
> > interrupts are enabled.
>
> That makes me a little uneasy. The locking
> mechanisms (and just about everything else) above the driver
> seem to change frequently. This involves not just the VFS but
> the tty core as well.
>
> If you are confident this will not change, I will
> switch to spin_lock(). I used spin_lock_irqsave() to be
> more robust against changes to behavior outside my driver.

The same function contains a copy_from_user(), which cannot
be called with interrupts disabled, so yes, I am very certain
it will not change.

Arnd <><
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