From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: sendmmsg: put_user vs __put_user
Date: Sat, 31 Mar 2012 17:27:10 -0400 (EDT)
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=46rom: Ulrich Drepper <drepper@gmail.com>
Date: Sat, 31 Mar 2012 08:30:25 -0400

> On Fri, Mar 30, 2012 at 20:51, David Miller <davem@davemloft.net> wro=
te:
>> Compat processes are not able to generate virtual addresses anywhere
>> near the range where the kernel resides, so the address range
>> verification done by put_user() is completely superfluous and
>> therefore not necessary. =A0The normal exception handling done by th=
e
>> access is completely sufficient.
>=20
> I was more thinking about the effects of might_fault() then additiona=
l tests.

This is very clearly in a context where locks are not held and sleeping
would be fine, so I don't see any value in that either.