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Date:   Sat, 2 Oct 2021 14:31:32 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Alexander Popov <alex.popov@linux.com>,
        Jonathan Corbet <corbet@lwn.net>,
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Subject: Re: [PATCH] Introduce the pkill_on_warn boot parameter
Message-ID: <20211002143132.3a51a8e0@oasis.local.home>
In-Reply-To: <YVifGtn3LctrWOwg@zeniv-ca.linux.org.uk>
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        <YVifGtn3LctrWOwg@zeniv-ca.linux.org.uk>
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On Sat, 2 Oct 2021 18:04:10 +0000
Al Viro <viro@zeniv.linux.org.uk> wrote:

> > @@ -610,6 +611,9 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
> >  
> >  	print_oops_end_marker();
> >  
> > +	if (pkill_on_warn && system_state >= SYSTEM_RUNNING)
> > +		do_group_exit(SIGKILL);
> > +  
> 
> Wait a sec...  do_group_exit() is very much not locking-neutral.
> Aren't you introducing a bunch of potential deadlocks by adding
> that?

Perhaps add an irq_work() here to trigger the do_group_exit() from a
"safe" interrupt context?

-- Steve