For all of the KVM patches, please use KVM: x86: "x86/kvm" is used for guest-side code, and while I hope no one will conflate this with guest code, the consistency is helpful. On Mon, Jul 14, 2025, Peter Zijlstra wrote: > Replace the FASTOP1SRC2*() instructions. > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > --- > arch/x86/kvm/emulate.c | 34 ++++++++++++++++++++++++++-------- > 1 file changed, 26 insertions(+), 8 deletions(-) > > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -317,6 +317,24 @@ static int em_##op(struct x86_emulate_ct > ON64(case 8: __EM_ASM_1(op##q, rax); break;) \ > EM_ASM_END > > +/* 1-operand, using "c" (src2) */ > +#define EM_ASM_1SRC2(op, name) \ > + EM_ASM_START(name) \ > + case 1: __EM_ASM_1(op##b, cl); break; \ > + case 2: __EM_ASM_1(op##w, cx); break; \ > + case 4: __EM_ASM_1(op##l, ecx); break; \ > + ON64(case 8: __EM_ASM_1(op##q, rcx); break;) \ > + EM_ASM_END > + > +/* 1-operand, using "c" (src2) with exception */ > +#define EM_ASM_1SRC2EX(op, name) \ > + EM_ASM_START(name) \ > + case 1: __EM_ASM_1_EX(op##b, cl); break; \ > + case 2: __EM_ASM_1_EX(op##w, cx); break; \ > + case 4: __EM_ASM_1_EX(op##l, ecx); break; \ > + ON64(case 8: __EM_ASM_1(op##q, rcx); break;) \ This needs to be __EM_ASM_1_EX(). Luckily, KVM-Unit-Tests actually has testcase for divq (somewhere in the morass of testcases). I also now have an extension to the fastops selftest to explicitly test all four flavors of div-by-zero; I'll get it posted tomorrow. (also, don't also me how long it took me to spot the copy+paste typo; I was full on debugging the exception fixup code before I realized my local diff looked "odd", *sigh*)
