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Date: Fri, 6 Jan 2017 15:04:44 -0600
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Miroslav Benes <mbenes@suse.cz>
Cc: Jessica Yu <jeyu@redhat.com>, Jiri Kosina <jikos@kernel.org>,
 Petr Mladek <pmladek@suse.com>, linux-kernel@vger.kernel.org,
 live-patching@vger.kernel.org, Michael Ellerman <mpe@ellerman.id.au>,
 Heiko Carstens <heiko.carstens@de.ibm.com>, x86@kernel.org,
 linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
 Vojtech Pavlik <vojtech@suse.com>, Jiri Slaby <jslaby@suse.cz>,
 Chris J Arges <chris.j.arges@canonical.com>,
 Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@kernel.org>,
 Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v3 13/15] livepatch: change to a per-task consistency model
Message-ID: <20170106210444.o35ajlxnfow27p33@treble>
References: <cover.1481220077.git.jpoimboe@redhat.com>
 <eeda3a8cf83bcbb569db4774c646ad739b8db415.1481220077.git.jpoimboe@redhat.com>
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On Thu, Jan 05, 2017 at 10:34:57AM +0100, Miroslav Benes wrote:
> 
> > @@ -740,6 +809,14 @@ int klp_register_patch(struct klp_patch *patch)
> >  		return -ENODEV;
> >  
> >  	/*
> > +	 * Architectures without reliable stack traces have to set
> > +	 * patch->immediate because there's currently no way to patch kthreads
> > +	 * with the consistency model.
> > +	 */
> > +	if (!klp_have_reliable_stack() && !patch->immediate)
> > +		return -ENOSYS;
> > +
> 
> I think an error message (pr_err) would be appropriate here. 
> 
> $ insmod patch_1.ko
> insmod: ERROR: could not insert module patch_1.ko: Function not implemented
> 
> is not helpful much :)

Ok :-)

-- 
Josh