Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1710752 > unrolled thread

Re: SIGNAL_UNKILLABLE and init again

Started byJamie Iles <jamie.iles@oracle.com>
First post2017-08-14 11:40 +0200
Last post2017-08-14 18:30 +0200
Articles 2 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.


Contents

  Re: SIGNAL_UNKILLABLE and init again Jamie Iles <jamie.iles@oracle.com> - 2017-08-14 11:40 +0200
    Re: SIGNAL_UNKILLABLE and init again Oleg Nesterov <oleg@redhat.com> - 2017-08-14 18:30 +0200

#1710752 — Re: SIGNAL_UNKILLABLE and init again

FromJamie Iles <jamie.iles@oracle.com>
Date2017-08-14 11:40 +0200
SubjectRe: SIGNAL_UNKILLABLE and init again
Message-ID<uek0N-2qo-9@gated-at.bofh.it>
Hi Oleg,

On Thu, Apr 27, 2017 at 01:16:51PM +0100, Jamie Iles wrote:
> On Wed, Apr 26, 2017 at 05:18:58PM +0200, Oleg Nesterov wrote:
> > Hi Jamie,
> > 
> > On 04/25, Jamie Iles wrote:
> > >
> > > Hi Oleg,
> > >
> > > I'm back looking at SIGNAL_UNKILLABLE and debugging child reapers again, 
> > > and the current issue is when running code in the target process, 
> > > SIGTRAP firing and that causing SIGNAL_UNKILLABLE protection to be 
> > > removed in force_sig_info():
> > >
> > > 	if (action->sa.sa_handler == SIG_DFL)
> > > 		t->signal->flags &= ~SIGNAL_UNKILLABLE;
> > 
> > Yes, this is what I meant when I said force_sig_info() needs changes too.
> > I was going to fix it "tomorrow" but I was distracted and then forgot.
> > 
> > >   @@ -1185,7 +1185,7 @@ force_sig_info(int sig, struct siginfo *info, struct task_struct *t)
> > >    			recalc_sigpending_and_wake(t);
> > >    		}
> > >    	}
> > >   -	if (action->sa.sa_handler == SIG_DFL)
> > >   +	if (action->sa.sa_handler == SIG_DFL && !t->ptrace)
> > >    		t->signal->flags &= ~SIGNAL_UNKILLABLE;
> > >    	ret = specific_send_sig_info(sig, info, t);
> > >    	spin_unlock_irqrestore(&t->sighand->siglock, flags);
> > 
> > Not sure, let me think a bit more... and this is not enough anyway.
> > 
> > perhaps we should start with this simple change, but the "real" fix
> > needs a lot of cleanups, although I am not sure if we will ever do this.
> 
> Okay, sounds good.  I'm happy to spend more time looking at this if you 
> have suggestions - in the context of namespaces and containers this 
> seems more relevant than when it was just the system init that we were 
> protecting.

Any objections to moving ahead with this patch?

Thanks,

Jamie

[toc] | [next] | [standalone]


#1711176

FromOleg Nesterov <oleg@redhat.com>
Date2017-08-14 18:30 +0200
Message-ID<ueqpC-6qC-77@gated-at.bofh.it>
In reply to#1710752
Hi Jamie,

On 08/14, Jamie Iles wrote:
>
> > > Not sure, let me think a bit more... and this is not enough anyway.
> > > 
> > > perhaps we should start with this simple change, but the "real" fix
> > > needs a lot of cleanups, although I am not sure if we will ever do this.
> > 
> > Okay, sounds good.  I'm happy to spend more time looking at this if you 
> > have suggestions - in the context of namespaces and containers this 
> > seems more relevant than when it was just the system init that we were 
> > protecting.
> 
> Any objections to moving ahead with this patch?

Oh, sorry.

OK, lets do this simple change then try to improve this logic further.

I'm afraid you need to re-send your patch, sorry.

Oleg.

[toc] | [prev] | [standalone]


Back to top | Article view | linux.kernel


csiph-web