BUG: scheduling while atomic

[Arun KS]

Hi Dave,

Thanks for your reply.

On Wed, Apr 18, 2012 at 1:01 PM, Dave Hylands <dhylands at gmail.com> wrote:

> Hi Arun,
>
> On Tue, Apr 17, 2012 at 11:44 PM, Arun KS <getarunks at gmail.com> wrote:
> >
> > Hello Guys,
> >
> > System is working normal after this BUG.
> > PC is at 0x400b4614, probably a mmaped address.
> >
> > Just wondering how can this BUG happen when a process is running in user
> > space.
> >
> > Can it be something like this
> > 1) enter to kernel from userspace through some system call.
> > 2) kernel disables the interrupt and return to user space.
>
> Don't do that
>

I don't do that. This scenario mentioned is a just a wild guess.

>
> > 3) and now it can happen in user space?
>
> Because something in userspace made a blocking call which would cause
> a context switch to occur and your driver erroneously left interrupts
> disabled.
>
In that case, my system should have been unstable afterwards if interrupts
are left disabled. But that is not happening.

If we return to user space with interrupts disabled, can we switch back
again to kernel using a system cal(because interrupts are already disabled)?

Arun


> --
> Dave Hylands
> Shuswap, BC, Canada
> http://www.davehylands.com
>
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