From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Subject: Re: [PATCH v2] xen/console: buffer and show origin of guest PV writes Date: Mon, 09 Sep 2013 07:14:25 -0700 Message-ID: References: <522DD143.8050601@tycho.nsa.gov> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <522DD143.8050601@tycho.nsa.gov> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Daniel De Graaf Cc: Andrew Cooper , JBeulich@suse.com, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 09/09/2013 06:46, "Daniel De Graaf" wrote: > On 09/09/2013 07:13 AM, Keir Fraser wrote: >> On 16/08/2013 20:01, "Daniel De Graaf" wrote: >> >>> Guests other than domain 0 using the console output have previously been >>> controlled by the VERBOSE define, but with no designation of which >>> guest's output was on the console. This patch converts the HVM output >>> buffering to be used by all domains, line buffering their output and >>> prefixing it with the domain ID. This is especially useful for debugging >>> stub domains. >>> >>> Signed-off-by: Daniel De Graaf >> >> This seems good, but, if we process and buffer dom0's output, we lose the >> possibility of running a terminal session in dom0 over the Xen console. >> Personally I do that quite a bit -- serial access only, get Xen's debugging >> there, but also can log in to dom0. Does noone else?? > > I do care about this use case (I also use it rather often), and it is > preserved > - this patch explicitly does not buffer or insert characters in dom0's output. > This means that we waste the 80-byte buffer for dom0, but I didn't think it > was > worth special-casing dom0 there too (also, doing that might break a PVH dom0 > that uses the HVM output - if that method is available, which I did not > check). That's great, but then the patch header is wrong as the output buffering is not used by *all* domains. Make it clear that dom0 is unaffected and then: Acked-by: Keir Fraser -- Keir