From mboxrd@z Thu Jan 1 00:00:00 1970 From: julien.grall@linaro.org (Julien Grall) Date: Thu, 12 Feb 2015 13:20:19 +0800 Subject: [PATCH] xen/arm: allow console=hvc0 to be omitted for guests In-Reply-To: <1423716873.27551.30.camel@citrix.com> References: <1422626319-30752-1-git-send-email-ard.biesheuvel@linaro.org> <1423553200.5851.15.camel@citrix.com> <1423558788.5851.17.camel@citrix.com> <1423716873.27551.30.camel@citrix.com> Message-ID: <54DC3813.2020908@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 12/02/2015 12:54, Ian Campbell wrote: > On Thu, 2015-02-12 at 04:35 +0000, Stefano Stabellini wrote: >> On Tue, 10 Feb 2015, Ian Campbell wrote: >>> On Tue, 2015-02-10 at 15:51 +0800, Ard Biesheuvel wrote: >>>>> FWIW on x86 this doesn't depend on console_set_on_cmdline, does it need >>>>> to here? >>>>> >>>> >>>> I didn't check the code, but it seems inappropriate to add a preferred >>>> console implicitly if the user has set 'console=' on the command line. >>> >>> I had been thinking that add_preferred_console would DTRT, but it seems >>> not. Seems strange that most calls to it do not check if the console is >>> already set, but it does seem like the right thing in this case. >>> >>>>> On x86 it does depend on !xen_initial_domain. I suppose on the principal >>>>> that a VT is normally available there. I suppose that doesn't apply to >>>>> ARM so much, although it could. >>>>> >>>> >>>> OK, I got confused by the xen_guest_init(). So do you mean if if >>>> (!xen_initial_domain) should be added? >>> >>> (dom0 is "Just A Guest" too ;-)) >>> >>> Adding it would be consistent with x86, I'm not precisely sure if that >>> is important or desirable in this case. I'd be inclined to start with >>> the if there. >> >> The reasoning is that dom0 command line arguments come from its old >> native grub stanza, therefore the console parameter is incorrect, right? >> As opposed to regular domUs, that being freshly installed, are supposed >> to have the correct console parameter? > > Other way around I think, dom0 has the correct stuff from grub.cfg > whereas the guest may not. Yes, currently for ARM guest you have to add 'extra="console=hvc0"' in the configuration file. Regards, -- Julien Grall