On Tue, 03 Jul 2007 23:36:22 +0200
Morten Helgesen [off-list ref] wrote:

 /*
 > Problems to take into account are:
 >       -1- Interrupts that empty part of the buffer.
->       -2- page faults on the access to userspace. 
+>       -2- Page faults on access to userspace. 

#2 no longer applies (don't before the caller)

 >       -3- Other processes that are also trying to do a "write".   

#3 no longer applies (locked by tty layer)

-	/* get exclusive "write" access to this port (problem 3) */
+	/* Get exclusive "write" access to this port (problem 3) */
 	/* This is not a spinlock because we can have a disk access (page 
-		 fault) in copy_from_user */

No copy_from_user any more. Actually that locking code wants review and
maybe removal so is another project altogether


Definitely an improvement

Acked-by: Alan Cox <redacted>