Re: [PATCH v3] seccomp: add ptrace options for suspend/resume

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From	Oleg Nesterov <oleg@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3] seccomp: add ptrace options for suspend/resume
Date	Sat, 06 Jun 2015 01:50:02 +0200
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On 06/05, Tycho Andersen wrote:
>
> right thing to do, just leave out the definition of
> may_suspend_seccomp all together, or add in another if defined() in
> the header?

Just declare it unconditionally in .h. The kernel relies on this kind
of dead-code elimination anyway. For example, please look at
"extern void __put_user_bad(void)" in uaccess.h.

IOW,

	extern void undefined_func(void);

	if (0)
		undefined_func();

should be safe.

> Maybe we will get rid of this pesky function all together though...

Yes ;)

Oleg.

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Re: [PATCH v3] seccomp: add ptrace options for suspend/resume Oleg Nesterov <oleg@redhat.com> - 2015-06-06 01:50 +0200

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