summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJan Beulich <jbeulich@suse.com>2021-09-30 14:17:41 +0200
committerJuergen Gross <jgross@suse.com>2021-10-05 08:36:00 +0200
commitadf330a7cd64a8bb959dc48a9c282285c1d5b4d5 (patch)
tree5388e0c7393cba01e0c544dcb5cc75bbe35642b8
parentcae7d81a3730dfe08623f8c1083230c8d0987639 (diff)
downloadlinux-adf330a7cd64a8bb959dc48a9c282285c1d5b4d5.tar.bz2
xen/x86: make "earlyprintk=xen" work better for PVH Dom0
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 <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/4fd89dcb-cfc5-c740-2e94-bb271e432d3e@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
-rw-r--r--drivers/tty/hvc/hvc_xen.c9
1 files changed, 4 insertions, 5 deletions
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 92c9a476defc..ee7ea8d762fa 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -621,17 +621,16 @@ static void xenboot_write_console(struct console *console, const char *string,
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)