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Date: Tue, 18 Nov 2008 17:22:07 -0800
From: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
To: Oleg Nesterov <oleg@redhat.com>
Cc: ebiederm@xmission.com, daniel@hozac.com, xemul@openvz.org,
       containers@lists.osdl.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH][v2] Define/use siginfo_from_ancestor_ns()
Message-ID: <20081119012207.GA19092@us.ibm.com>
References: <20081115212133.GA32140@us.ibm.com> <20081118175336.GA14178@redhat.com>
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| 
| > +static inline int siginfo_from_ancestor_ns(siginfo_t *info)
| > +{
| > +	return SI_FROMUSER(info) && (info->si_pid == 0);
| > +}
| 
| Yes, this is problem... I doubt we can rely on !si_pid here.
| More on this later.

BTW, rather than clearing SIG_FROM_USER in send_signal(), can we
keep it till we dequeue the signal ? Yes, collect_signal() would
need to consider this flag. But when we dequeue, we can note that
it was from user and use that in the siginfo_from_ancestor() ?

Sukadev