Re: netpoll trapped question

[Matt Mackall]

On Tue, Sep 07, 2004 at 12:53:17PM -0400, Jeff Moyer wrote:
> mpm> A random lock private to a given driver, for instance one taken on
> mpm> entry to the IRQ handler. If said driver tries to do a printk inside
> mpm> that lock and we recursively call the handler in netconsole, we're in
> mpm> trouble.  These are the issues that will have to be cleaned up in
> mpm> individual drivers. So far, I haven't seen any reports, but I'm pretty
> mpm> sure such cases exist. I suppose it's also possible for us to disable
> mpm> recursion in netconsole instead of at the netpoll level.
> 
> Recursion in netconsole is protected by the console semaphore.

Yes, true. But we're still in trouble if we have nic irq handler ->
take private lock -> printk -> netconsole -> nic irq handler -> take
private lock. See?

-- 
Mathematics is the supreme nostalgia of our time.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/