Re: [PATCH] n_hdlc fix read and write locking

[Paul Fulghum]

On 10/25/2010 2:05 PM, Andrew Morton wrote:
> And a signed-off-by:, please.

OK

> It's not a bug afaict, but beware that a copy_to_user() will
> unconditionally flip this task back into TASK_RUNNING state if it takes
> a pagefault.  This means that the below schedule() will fall straight
> through.  It looks like the code will handle this correctly?  If so,
> it's just a little suboptimal.

copy_to_user is only called when data is available to
complete the read and break terminates the loop without
calling schedule().

>> +	set_current_state(TASK_RUNNING);
> 
> We normally use __set_current_state() here - it saves a few cycles.

I'll change it to __set_current_state() and resubmit.

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Paul Fulghum
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