From 79902f7c4f7595d9587e916fdf78a06c198a5c55 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Mon, 28 Jan 2008 11:28:55 +0000 Subject: [PATCH] vmx realmode: Multiple I/O reads to qemu in an instruction is not allowed. But we do allow, for example, a read followed by a write (e.g., MOVS within video RAM). Signed-off-by: Keir Fraser --- xen/arch/x86/hvm/vmx/realmode.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/xen/arch/x86/hvm/vmx/realmode.c b/xen/arch/x86/hvm/vmx/realmode.c index b9664ed42c..b5952953c4 100644 --- a/xen/arch/x86/hvm/vmx/realmode.c +++ b/xen/arch/x86/hvm/vmx/realmode.c @@ -534,12 +534,6 @@ static void realmode_emulate_one(struct realmode_emulate_ctxt *rm_ctxt) goto fail; } - if ( io_completed && curr->arch.hvm_vmx.real_mode_io_in_progress ) - { - gdprintk(XENLOG_ERR, "Multiple I/O transactions in a single insn.\n"); - goto fail; - } - if ( rc == X86EMUL_UNHANDLEABLE ) { gdprintk(XENLOG_ERR, "Failed to emulate insn.\n"); @@ -547,7 +541,13 @@ static void realmode_emulate_one(struct realmode_emulate_ctxt *rm_ctxt) } if ( rc == X86EMUL_RETRY ) - return; + { + BUG_ON(!curr->arch.hvm_vmx.real_mode_io_in_progress); + if ( !io_completed ) + return; + gdprintk(XENLOG_ERR, "Multiple I/O reads in a single insn.\n"); + goto fail; + } if ( curr->arch.hvm_vmx.real_mode_io_in_progress && (get_ioreq(curr)->vp_ioreq.dir == IOREQ_READ) ) -- 2.30.2