Re: [PATCH v6 01/10] x86/retpoline: Add initial retpoline support

From: David Woodhouse
Date: Mon Jan 08 2018 - 07:46:00 EST



> On Mon, Jan 08, 2018 at 10:53:02AM +0000, David Woodhouse wrote:
>> On Mon, 2018-01-08 at 11:45 +0100, Peter Zijlstra wrote:
>> >
>> >
>> > Should this not use local name labels instead?
>> >
>> > .macro RETPOLINE_JMP reg:req
>> > ÂÂÂÂÂÂÂÂcallÂÂÂÂ.Ldo_rop_\@
>> > .Lspec_trap_\@:
>> > ÂÂÂÂÂÂÂÂpause
>> > ÂÂÂÂÂÂÂÂjmp .Lspec_trap_\@
>> > .Ldo_rop_\@:
>> > ÂÂÂÂÂÂÂÂmovÂÂÂÂÂ\reg, (%_ASM_SP)
>> > ÂÂÂÂÂÂÂÂret
>> > .endm
>>
>> Not if you want to be able to use them twice in the same .S file.
>
> Should work fine, the \@ expands to a per-instance magic thing IIRC. All
> the PTI helpers do this too and that works just fine, see
> arch/x86/entry/calling.h
>

Ah, OK. Will do that when home in a few hours then.

--
dwmw2