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From:   Nadav Amit <namit@vmware.com>
To:     Borislav Petkov <bp@alien8.de>
CC:     Peter Zijlstra <peterz@infradead.org>,
        Rick Edgecombe <rick.p.edgecombe@intel.com>,
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Subject: Re: [PATCH v2 06/20] x86/alternative: use temporary mm for text
 poking
Thread-Topic: [PATCH v2 06/20] x86/alternative: use temporary mm for text
 poking
Thread-Index: AQHUt2sRlZaCHhQDiEGNmzE5nFIfqqXRA/aAgAAZ9ACAABHSgIAAWTuA
Date:   Tue, 5 Feb 2019 17:54:56 +0000
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> On Feb 5, 2019, at 4:35 AM, Borislav Petkov <bp@alien8.de> wrote:
>=20
> On Tue, Feb 05, 2019 at 12:31:46PM +0100, Peter Zijlstra wrote:
>> ...
>>=20
>> 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.
>=20
> 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.

I added a short comment for v3 above each BUG_ON().

> And since text_poke() can't fail, then it doesn't need a retval too.
> AFAICT, nothing is actually using it.

As Peter said, this is addressed in a separate patch (one patch per logical
change).