The xen_hvm_early_write() path better wouldn't be taken in this case;
while port 0xE9 can be used, the hypercall path is quite a bit more
efficient. Put that first, as it may also work for DomU-s (see also
xen_raw_console_write()).

While there also bail from the function when the first
domU_write_console() failed - later ones aren't going to succeed.

Signed-off-by: Jan Beulich <jbeul...@suse.com>
Reviewed-by: Juergen Gross <jgr...@suse.com>

--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -632,17 +632,16 @@ static void xenboot_write_console(struct
        unsigned int linelen, off = 0;
        const char *pos;
 
+       if (dom0_write_console(0, string, len) >= 0)
+               return;
+
        if (!xen_pv_domain()) {
                xen_hvm_early_write(0, string, len);
                return;
        }
 
-       dom0_write_console(0, string, len);
-
-       if (xen_initial_domain())
+       if (domU_write_console(0, "(early) ", 8) < 0)
                return;
-
-       domU_write_console(0, "(early) ", 8);
        while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
                linelen = pos-string+off;
                if (off + linelen > len)

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