Re: [PATCH/RFC] remove irqs_disabled warning from local_bh_enable

From: Michael Buesch
Date: Fri Jun 20 2008 - 12:02:04 EST


On Friday 20 June 2008 17:55:41 Ingo Molnar wrote:
>
> * Michael Buesch <mb@xxxxxxxxx> wrote:
>
> > On Friday 20 June 2008 17:27:48 Ingo Molnar wrote:
> > > [<c012b361>] local_bh_enable_ip+0xd1/0xe0
> > > [<c08d9f9f>] _spin_unlock_bh+0x2f/0x40
> > > [<c0471b92>] vortex_timer+0xe2/0x3e0
> >
> > > real bug or false positive?
> >
> > Well, a timer runs with IRQs disabled, no? So this would be a bug.
>
> indeed - agreed :) [no time for me to fix it, but can test any rfc patch.]

A quick workaround always is to convert the lock into an _irqsafe lock.
Although it introduces higher overhead (interrupt-wise), it prevents the bug.
A real fix would require to understand the locking in the driver, which I
don't, as I never looked at the driver. :)

--
Greetings Michael.
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