[svsm-devel] [PATCH v4 05/15] x86/sev: Use kernel provided SVSM Calling Areas

[Borislav Petkov]

Ok,

I think this is very readable and clear what's going on:

static __always_inline void issue_svsm_call(struct svsm_call *call, u8 *pending)
{
        register unsigned long rax asm("rax") = call->rax;
        register unsigned long rcx asm("rcx") = call->rcx;
        register unsigned long rdx asm("rdx") = call->rdx;
        register unsigned long r8  asm("r8")  = call->r8;
        register unsigned long r9  asm("r9")  = call->r9;

        call->caa->call_pending = 1;

        asm volatile("rep; vmmcall\n\t"
                     : "+r" (rax), "+r" (rcx), "+r" (rdx), "+r" (r8), "+r" (r9));

        xchg(pending, 1);

        call->rax_out = rax;
        call->rcx_out = rcx;
        call->rdx_out = rdx;
        call->r8_out = r8;
        call->r9_out = r9;
}

and the asm looks ok but the devil's in the detail.

-- 
Regards/Gruss,
    Boris.

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