[PATCH] xen/hvc: If we use xen_raw_printk let it also work on HVM guests.

From: Konrad Rzeszutek Wilk
Date: Fri Aug 09 2013 - 10:55:46 EST

The xen_raw_printk works great for debugging purposes and for
it print anything the Xen hypervisor has to be built with 'debug=y'.

As such there is no difference between a PV or an PVHVM guest
using the hypercall, so lets use it.

Lastly if the hyper-page is not setup yet (for example during
early HVM boot), then use the 0xe9 port if it has detected
that it is running under an Xen hypervisor.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
drivers/tty/hvc/hvc_xen.c | 12 +++++++++++-
1 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 682210d..69454a0 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -641,7 +641,17 @@ struct console xenboot_console = {

void xen_raw_console_write(const char *str)
- dom0_write_console(0, str, strlen(str));
+ if (!xen_domain())
+ return;
+ if (xen_pv_domain())
+ dom0_write_console(0, str, strlen(str));
+ else if (xen_hvm_domain() || xen_cpuid_base()) {
+ /* The hyperpage has not been setup yet. */
+ int i, len = strlen(str);
+ for (i = 0; i < len; i++)
+ outb(str[i], 0xe9);
+ }

void xen_raw_printk(const char *fmt, ...)

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