From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Laight <David.Laight@ACULAB.COM>
Subject: RE: [PATCH 15/17] switch kernel_sendmsg() and kernel_recvmsg() to
 iov_iter_kvec()
Date: Tue, 14 Apr 2015 16:36:36 +0000
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Cc: "davem@davemloft.net" <davem@davemloft.net>,
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To: 'Al Viro' <viro@ZenIV.linux.org.uk>
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From: Al Viro 
> Sent: 14 April 2015 17:34
> On Tue, Apr 14, 2015 at 04:21:02PM +0000, David Laight wrote:
> 
> > Massive NAK.
> > This breaks any code that is using msg_control to set SCTP parameters
> > when sending data.
> 
> 	Huh?  ->sendmsg() expects ->msg_control already in kernel space;
> it's ->recvmsg() that plays silly buggers with userland pointers there.

I read your commit message as implying that you hadn't found any
users of kernel_sendmsg() that used msg_control.
Not that the data was always read from kernel space.

	David