Re: [BUG] 2.6.25-rc5-mm1 kernel panic with "Exception: 501 " onpowerpc

From: Michael Ellerman
Date: Wed Mar 12 2008 - 18:26:26 EST


On Wed, 2008-03-12 at 11:51 -0600, Matthew Wilcox wrote:
> On Wed, Mar 12, 2008 at 10:46:45AM -0700, Andrew Morton wrote:
> > On Wed, 12 Mar 2008 18:25:37 +0530 Kamalesh Babulal <kamalesh@xxxxxxxxxxxxxxxxxx> wrote:
> > Beats me. Maybe we're still enabling interrupts too early. But the new
> > semaphore code got fixed (didn't it?)
>
> On the 7th, according to my records. Easy to check -- look in
> kernel/semaphore.c and see whether down() is using spin_lock_irqsave
> (good) or spin_lock_irq (bad).

down() looks OK, but there's still a spin_lock_irq() in __down_common(),
although I don't know if it makes sense for us to be in __down() at that
stage.

cheers

--
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person

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