From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <5144D524.4000302@web.de>
Date: Sat, 16 Mar 2013 21:25:08 +0100
From: Jan Kiszka <jan.kiszka@web.de>
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Subject: Re: [Xenomai] __get_user/__put_user
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: Xenomai <xenomai@xenomai.org>

On 2013-03-16 21:19, Gilles Chanteperdrix wrote:
> =

> Hi,
> =

> xenomai asm-generic/syscall.h defines __xn_put_user/__xn_get_user as
> aliases for __put_user/__get_user, which implementation, for the ARM
> architecture calls might_fault() which triggers an ipipe_root_only() chec=
k.
> =

> So, the question is, what is the best way of avoiding this issue? Remove
> the call to might_fault() when compiling with CONFIG_IPIPE enabled?
> Define __ipipe_safe_put_user which avoids the call to might_fault() ?

Adjust might_fault() in a way that it only considers atomic non-root
contexts as problematic.

Jan


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