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Re: [PATCH v5] xen/common: add keyhandler to show Xen command line


  • To: Jan Beulich <jbeulich@xxxxxxxx>
  • From: dmukhin@xxxxxxxx
  • Date: Thu, 13 Aug 2026 11:36:17 -0700
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  • Cc: dmukhin@xxxxxxxx, andrew.cooper3@xxxxxxxxxx, anthony.perard@xxxxxxxxxx, julien@xxxxxxx, michal.orzel@xxxxxxx, roger@xxxxxxxxxxxxxx, sstabellini@xxxxxxxxxx, xen-devel@xxxxxxxxxxxxxxxxxxxx
  • Delivery-date: Thu, 13 Aug 2026 18:36:36 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
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On Thu, Aug 13, 2026 at 08:00:11AM +0200, Jan Beulich wrote:
> On 13.08.2026 05:51, dmukhin@xxxxxxxx wrote:
> > From: Denis Mukhin <dmukhin@xxxxxxxx> 
> > 
> > Currently there's no way to print Xen command line on the emergency
> > console for debugging purposes when 'xl' is unavailable.
> > 
> > Add new keyhander '?' to do command line printout.
> > 
> > To allow built-in command printout, drop __initconst in
> > 'opt_builtin_cmdline' declaration.
> > 
> > Signed-off-by: Denis Mukhin <dmukhin@xxxxxxxx>
> > ---
> > Changes since v4:
> > - promote opt_builtin_cmdline to __ro_after_init and use it for
> >   built-in command line reporting
> > - account for empty saved_cmdline
> > - adjust register_keyhandler() call - use '?'
> 
> This isn't quite what I was expecting, following the feedback you got on
> v4. My expectation was that we'd see a 2-patch series, first patch moving
> non-help stuff out of the 'h' handler, second patch adding the dumping of
> the command line. Naturally the new handler then wouldn't be named
> show_cmdline(). I'd then further expect tat no new use of
> register_keyhandler() would be necessary: The handler itself would live
> in keyhandler.c, and print_version() would then be accompanied by a new
> print_cmdline().

I see, will update.

> 
> Jan
> 



 


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