diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 23bd7f078a..0c60faa39d 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -567,9 +567,15 @@ static int cf_check hvm_print_line( ASSERT(bytes == 1 && port == XEN_HVM_DEBUGCONS_IOPORT); - /* Deny any input requests. */ - if ( dir != IOREQ_WRITE ) - return X86EMUL_UNHANDLEABLE; + if ( dir == IOREQ_READ ) + { + /* + * According to Bochs documentation, reading from the E9 port should + * return 0xE9 if the "port E9 hack" is implemented. + */ + *val = XEN_HVM_DEBUGCONS_IOPORT; + return X86EMUL_OKAY; + } if ( !is_console_printable(c) ) return X86EMUL_OKAY;