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From:   Nick Desaulniers <ndesaulniers@google.com>
Date:   Tue, 5 Jun 2018 10:52:42 -0700
Message-ID: <CAKwvOdk0v4gY04_pbMeUT7Ly5oRHetKorQXnjp_UVBabK74Ekw@mail.gmail.com>
Subject: Re: [PATCH v2 2/2] x86: paravirt: make native_save_fl extern inline
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On 06/05/18 10:28, H. Peter Anvin wrote:
> On 06/05/18 10:05, Nick Desaulniers wrote:
>> +
>> +/*
>> + * void native_restore_fl(unsigned long flags)
>> + * %rdi: flags
>> + */
>> +ENTRY(native_restore_fl)
>> +    push %_ASM_DI
>> +    popf
>> +    ret
>> +ENDPROC(native_restore_fl)
>> +EXPORT_SYMBOL(native_restore_fl)
>>
>
> To work on i386, this would have to be %_ASM_AX in that case.

?

Does the kernel have a different calling convention for 32b x86? How
does that work? regparm=3? Does that need to be added to the
declaration?

> Something like this added to <asm/asm.h> might be useful; then you can
> simply:
>
>       push %_ASM_ARG1
>
> Version with fixed typo...

Oh, nice, thanks! I'll pick this up and add it to my patch set for v3
(or did you want me to review/sign-off now?) I can pick up Sedat's
suggestion.
-- 
Thanks,
~Nick Desaulniers