On 8/8/26 4:38 AM, [email protected] wrote:
On Fri, Aug 07, 2026 at 05:44:41PM -0700, Stefano Stabellini wrote:
On Mon, 3 Aug 2026, [email protected] wrote:
From: Denis Mukhin <[email protected]>
Currently there's no way to print Xen command line on the emergency
console for debugging purposes (e.g. 'xl' is not available in dom0).
Add new keyhander 'X' to do command line printout.
Signed-off-by: Denis Mukhin <[email protected]>
---
v1: https://lore.kernel.org/xen-devel/[email protected]/
Changes since v1:
- moved implementation into kernel.c
---
xen/common/kernel.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/xen/common/kernel.c b/xen/common/kernel.c
index d1bef9ac2b2b..9f334c92e3ab 100644
--- a/xen/common/kernel.c
+++ b/xen/common/kernel.c
@@ -5,6 +5,7 @@
*/
#include <xen/init.h>
+#include <xen/keyhandler.h>
#include <xen/lib.h>
#include <xen/errno.h>
#include <xen/param.h>
@@ -505,6 +506,21 @@ static int __init cf_check param_init(void)
__initcall(param_init);
#endif
+static void cf_check show_hypervisor_info(unsigned char key)
+{
+ printk("'%c' pressed -> showing hypervisor information\n", key);
+ printk("Command line: %s\n", saved_cmdline);
if CONFIG_CMDLINE_OVERRIDE is defined, saved_cmdline is empty. We could
at least do this:
#ifdef CONFIG_CMDLINE_OVERRIDE
printk("Bootloader command line ignored (CONFIG_CMDLINE_OVERRIDE=y)\n");
#else
printk("Command line: %s\n", saved_cmdline);
#endif
Actually, CONFIG_CMDLINE can set the built-in command line which can be
non-empty.
Perhaps, something like this:
printk("Command line (built-in): %s\n", opt_builtin_cmdline);
#ifndef CONFIG_CMDLINE_OVERRIDE
printk("Command line: %s\n", saved_cmdline);
#endif
What do you think?
Considering that opt_builtin_cmdline is declared as __initconst won't it
be an issue to print it in non-init function (show_hypervisor_info())?
In other words, I expected that __init section should be freed at some
point and I expect that it should be data abort here.
~ Oleksii
