From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "H. Peter Anvin" , Konrad Rzeszutek Wilk , "H. Peter Anvin" Subject: [ 07/46] doc, xen: Mention earlyprintk=xen in the documentation. Date: Fri, 1 Mar 2013 11:44:55 -0800 Message-Id: <20130301194433.063903763@linuxfoundation.org> In-Reply-To: <20130301194432.263409302@linuxfoundation.org> References: <20130301194432.263409302@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konrad Rzeszutek Wilk commit 2482a92e7d17187301d7313cfe5021b13393a0b4 upstream. The earlyprintk for Xen PV guests utilizes a simple hypercall (console_io) to provide output to Xen emergency console. Note that the Xen hypervisor should be booted with 'loglevel=all' to output said information. Reported-by: H. Peter Anvin Signed-off-by: Konrad Rzeszutek Wilk Link: http://lkml.kernel.org/r/1361825650-14031-2-git-send-email-konrad.wilk@oracle.com Signed-off-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 3 +++ 1 file changed, 3 insertions(+) --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -742,6 +742,7 @@ bytes respectively. Such letter suffixes earlyprintk= [X86,SH,BLACKFIN] earlyprintk=vga + earlyprintk=xen earlyprintk=serial[,ttySn[,baudrate]] earlyprintk=ttySn[,baudrate] earlyprintk=dbgp[debugController#] @@ -759,6 +760,8 @@ bytes respectively. Such letter suffixes The VGA output is eventually overwritten by the real console. + The xen output can only be used by Xen PV guests. + ekgdboc= [X86,KGDB] Allow early kernel console debugging ekgdboc=kbd