From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg KH Date: Tue, 27 Sep 2016 10:58:42 +0000 Subject: Re: [PATCH v3] console: Add persistent scrollback buffers for all VGA consoles Message-Id: <20160927105842.GA3922@kroah.com> List-Id: References: <1474236417-27150-1-git-send-email-manuel.schoelling@gmx.de> In-Reply-To: <1474236417-27150-1-git-send-email-manuel.schoelling@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: Manuel =?iso-8859-1?Q?Sch=F6lling?= Cc: plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, jslaby@suse.cz, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org On Mon, Sep 19, 2016 at 12:06:57AM +0200, Manuel Sch=F6lling wrote: > Add a scrollback buffers for each VGA console. The benefit is that > the scrollback history is not flushed when switching between consoles > but is persistent. > The buffers are allocated on demand when a new console is opened. >=20 > It always annoys me when I switch back to a console and I can just > read half of an error backtrace. This should fix issues like these. >=20 > This breaks tools like clear_console that rely on flushing the > scrollback history by switching back and forth between consoles > which is why this feature is disabled by default. > Use the escape sequence \e[3J instead for flushing the buffer. >=20 > Signed-off-by: Manuel Sch=F6lling > --- > Changes in v3: > - Add config option for this feature > - Fallback to old scrollback buffer if kcalloc() fails > - Remove ioctl() call again and add documentation about existing > escape sequence to flush the scrollback buffer > Changes in v2: > - Add ioctl() call to flush scrollback buffer > - (Patch v2 was not labeled as such, sorry) > --- > drivers/video/console/Kconfig | 23 +++++- > drivers/video/console/vgacon.c | 160 +++++++++++++++++++++++++++--------= ------ > 2 files changed, 128 insertions(+), 55 deletions(-) I need someone else to at least test this, and give an acked-by for it... thanks, greg k-h