Re: [PATCH -v2] kvm: Emulate MOVBE

[Borislav Petkov <bp@alien8.de>]

On Sun, Apr 21, 2013 at 01:46:50PM +0200, Borislav Petkov wrote:
> We probably need something with copying values to a temp variable or so.

Basically something like that:

        case 2:
                /*
                 * From MOVBE definition: "...When the operand size is 16 bits,
                 * the upper word of the destination register remains unchanged
                 * ..."
                 *
                 * Both casting ->valptr and ->val to u16 breaks strict aliasing
                 * rules so we have to do the operation almost per hand.
                 */
                tmp = (u16)ctxt->src.val;
                ctxt->dst.val &= ~0xffffUL;
                ctxt->dst.val |= (unsigned long)swab16(tmp);
		break;

This passes all gcc checks, even the stricter ones when building with W=3.

-- 
Regards/Gruss,
    Boris.

Sent from a fat crate under my desk. Formatting is fine.
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