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Date:   Tue, 5 Feb 2019 14:25:07 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Borislav Petkov <bp@alien8.de>
Cc:     Rick Edgecombe <rick.p.edgecombe@intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH v2 06/20] x86/alternative: use temporary mm for text
 poking
Message-ID: <20190205132507.GS17528@hirez.programming.kicks-ass.net>
References: <20190129003422.9328-1-rick.p.edgecombe@intel.com>
 <20190129003422.9328-7-rick.p.edgecombe@intel.com>
 <20190205095853.GJ21801@zn.tnic>
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On Tue, Feb 05, 2019 at 01:35:33PM +0100, Borislav Petkov wrote:
> On Tue, Feb 05, 2019 at 12:31:46PM +0100, Peter Zijlstra wrote:
> > ...
> >
> > So while in general I agree with BUG_ON() being undesirable, I think
> > liberal sprinking in text_poke() is fine; you really _REALLY_ want this
> > to work or fail loudly. Text corruption is just painful.
> 
> Ok. It would be good to have the gist of this sentiment in a comment
> above it so that it is absolutely clear why we're doing it.
> 
> And since text_poke() can't fail, then it doesn't need a retval too.
> AFAICT, nothing is actually using it.

See patch 12, that removes the return value (after fixing the few users
that currently 'rely' on it).