From: Jan Beulich Date: Tue, 18 Dec 2018 14:20:32 +0000 (+0100) Subject: x86emul: fix vector-length check for AVX512F scalar fused-multiply-add insns X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=1f2a4cb17b4b925dc279ab263907844ed5800f20;p=people%2Fandrewcoop%2Fxen.git x86emul: fix vector-length check for AVX512F scalar fused-multiply-add insns The check needs to happen whenever EVEX.b (SDM nomenclature) is clear, not just in the memory operand case. Signed-off-by: Jan Beulich Acked-by: Andrew Cooper --- diff --git a/xen/arch/x86/x86_emulate/x86_emulate.c b/xen/arch/x86/x86_emulate/x86_emulate.c index d6c97651e2..a3d7e33385 100644 --- a/xen/arch/x86/x86_emulate/x86_emulate.c +++ b/xen/arch/x86/x86_emulate/x86_emulate.c @@ -8532,11 +8532,9 @@ x86_emulate( case X86EMUL_OPC_EVEX_66(0x0f38, 0xbd): /* vfnmadd231s{s,d} xmm/mem,xmm,xmm{k} */ case X86EMUL_OPC_EVEX_66(0x0f38, 0xbf): /* vfnmsub231s{s,d} xmm/mem,xmm,xmm{k} */ host_and_vcpu_must_have(avx512f); - if ( ea.type == OP_MEM ) - { - generate_exception_if(evex.br, EXC_UD); + generate_exception_if(ea.type != OP_REG && evex.br, EXC_UD); + if ( !evex.br ) avx512_vlen_check(true); - } goto simd_zmm; case X86EMUL_OPC(0x0f38, 0xc8): /* sha1nexte xmm/m128,xmm */