From a05fc8e5be7fe6a079857279c973a8ebfad2e31d Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Tue, 6 Mar 2018 15:46:56 +0100 Subject: [PATCH] x86/emul: Fix the emulation of invlpga The instruction requires EFER.SVME set to be usable in the first place. Furthermore, the emulation doesn't handle ASIDs, so avoid giving the impression that they work. Permit ASID 0 which is reserved for non-root mode (in which case the instruction is identical to invlpg), but raise #UD for any other ASID. Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich master commit: a91b2ec337a45d5d98e5a4387aa6563bc5cdc4c9 master date: 2018-02-05 18:17:22 +0000 --- xen/arch/x86/x86_emulate/x86_emulate.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/xen/arch/x86/x86_emulate/x86_emulate.c b/xen/arch/x86/x86_emulate/x86_emulate.c index ff0a003902..f3578549b3 100644 --- a/xen/arch/x86/x86_emulate/x86_emulate.c +++ b/xen/arch/x86/x86_emulate/x86_emulate.c @@ -5065,8 +5065,15 @@ x86_emulate( break; case 0xdf: /* invlpga */ - generate_exception_if(!in_protmode(ctxt, ops), EXC_UD); + fail_if(!ops->read_msr); + if ( (rc = ops->read_msr(MSR_EFER, + &msr_val, ctxt)) != X86EMUL_OKAY ) + goto done; + /* Finding SVME set implies vcpu_has_svm(). */ + generate_exception_if(!(msr_val & EFER_SVME) || + !in_protmode(ctxt, ops), EXC_UD); generate_exception_if(!mode_ring0(), EXC_GP, 0); + generate_exception_if(_regs.ecx, EXC_UD); /* TODO: Support ASIDs. */ fail_if(ops->invlpg == NULL); if ( (rc = ops->invlpg(x86_seg_none, truncate_ea(_regs.r(ax)), ctxt)) ) -- 2.39.5