Messages in this thread | | | Date | Mon, 8 Jan 2018 14:25:12 -0800 | From | Andi Kleen <> | Subject | Re: [PATCH] x86/retpoline: Avoid return buffer underflows on context switch |
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> So pjt did alignment, a single unroll and per discussion earlier today > (CET) or late last night (PST), he only does 16.
I used the Intel recommended sequence, which recommends 32.
Not sure if alignment makes a difference. I can check.
> Why is none of that done here? Also, can we pretty please stop using > those retarded number labels, they make this stuff unreadable.
Personally I find the magic labels with strange ASCII characters far less readable than a simple number.
But can change it if you insist.
> Also, pause is unlikely to stop speculation, that comment doesn't make > sense. Looking at PJT's version there used to be a speculation trap in > there, but I can't see that here.
My understanding is that it stops speculation. But could also use LFENCE.
-Andi
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