Re: [gentoo-user] console scrollback (kernel 5.14)
On Sat, Sep 25, 2021 at 12:44 AM Jorge Almeida wrote: > > On Fri, Sep 24, 2021 at 5:29 PM Alan Mackenzie wrote: > > > > > attached. Please start again from a gentoo-sources without any previous > > traces of the scrollback patches, and apply that patch. _Surely_ it > > should work this time. > > > Sure enough, the patch was succesful. Unfortunately, I cannot test it, > > Anyway, I'll try again when I manage to fix or replace the computer > and I'll report then. > OK, the patch is working for me, kernel 5.14.4 (not the same computer---RIP the other one---, but same hard disk) Thanks Jorge Almeida
Re: [gentoo-user] console scrollback (kernel 5.14)
On Mon, Sep 27, 2021 at 12:51 AM Dale wrote: > > Jorge Almeida wrote: > > On Sun, Sep 26, 2021 at 6:24 PM antlists wrote: > > Hello, Wol and Dale > >> When you rebuild it, get a surge protector and then put a UPS behind > >> that ... snag is that's all extra expense :-( > >> > Hope that info helps. Also hope you can find something to prevent > future problems. > Thanks, Dale and Wol. I'll give it some thought. First thing is to replace the PSU and see how it goes. I may ask for your opinions before buying UPS & surge protector when I'll have it sorted out. Jorge
Re: [gentoo-user] console scrollback (kernel 5.14)
Jorge Almeida wrote: > On Sun, Sep 26, 2021 at 6:24 PM antlists wrote: > Hello, Wol and Dale >> When you rebuild it, get a surge protector and then put a UPS behind >> that ... snag is that's all extra expense :-( >> > Surge protectors: I googled it and mostly got bad reviews. Do they > _really_work? What would you recommend? It probably should be > something amazon-purchasable! Availability in my country is probably > limited (and overpriced to boot, I bet). > > UPS: never gave it serious thought, I had the impression there was too > much unclear stuff: for example, is it noisy (does it need a fan)? If > (when) some component needs replacement will I know it before > disaster? And does the replacement require a "qualified technician"? ( > Dale's description is not very reassuring!) > > Note that my lightning problem happened at night with both computer > and monitor powered down (but still connected to a wall outlet through > an interrupted extension; hence the "not-so-smart" self-qualifying...) > > Thanks for your suggestions > > Jorge > > I had lightening strike right down the road, about 1,000 feet as a bird flies. It took out some stuff at my neighbors, including a freezer which died a month later. It even blew light bulbs, I mean literally blew them. They exploded and glass went all over the room. I suggested surge protection for their computer, TV and such a while before that. Even with a virtually direct hit, the surge protectors kept working. Not long after that, they wanted a UPS for their computer but also wanted one for the TV, since the dish box takes a while to reload after the power blinks. So I helped them pick a fair sized UPS for the puter and a smaller one for the TV. The puter runs long enough to shutdown normally and the TV is protected for those little blinks in power that last just long enough to reset everything. One way to pick a decent surge device, look at the warranty. If it includes paying for items plugged in, then you're off to a good start at least. I just try to get as high a joule rating as I can. The reason for that, they can absorb more than one hit and still protect. While one large hit can disable protection, it can take out hundreds of smaller hits and still work. It all comes down to the quality of the MOVs and the design of the protector. If you use Amazon: APC, Belkin and Tripp Lite are some brands I've heard or seen are good. I've used a couple of those brands myself. I've always heard that the Monster brand is also good but a bit pricey. When I researched them long ago, they are some heavy duty built products so if a person has some serious power problems, they may be well worth the expense. I bought some on ebay that were Etekcity brand but it seems they no longer make them. I bought some that had a little over 5,000 joules of protection. The only thing I didn't like, if power fails, it stays off. It doesn't have a hardware switch but a circuit switch that resets on power loss. That can be a good thing in some situations but I don't like it. They are good protectors tho. Hope that info helps. Also hope you can find something to prevent future problems. Dale :-) :-)
Re: [gentoo-user] console scrollback (kernel 5.14)
On 26/09/2021 22:22, Jorge Almeida wrote: On Sun, Sep 26, 2021 at 6:24 PM antlists wrote: Hello, Wol and Dale When you rebuild it, get a surge protector and then put a UPS behind that ... snag is that's all extra expense :-( Surge protectors: I googled it and mostly got bad reviews. Do they _really_work? What would you recommend? It probably should be something amazon-purchasable! Availability in my country is probably limited (and overpriced to boot, I bet). Surge protectors are tricky. In the UK, our power supply is pretty clean so they're (almost) a waste of time. They should have a status on them, usually they're good for one shock and that's it. The big danger in many places is a lightning hit on overhead power lines. And if it's a storm you can have several hits in quick succession which will overwhelm the protector ... UPS: never gave it serious thought, I had the impression there was too much unclear stuff: for example, is it noisy (does it need a fan)? If (when) some component needs replacement will I know it before disaster? And does the replacement require a "qualified technician"? ( Dale's description is not very reassuring!) Again, you need a decent unit. And they're mostly a lot cheaper than a computer, so if they take the hit rather than your computer you're quids in whatever. But even if they're a not-very-good unit, if your local power is crappy they should clean it up and protect your computer to some extent. Note that my lightning problem happened at night with both computer and monitor powered down (but still connected to a wall outlet through an interrupted extension; hence the "not-so-smart" self-qualifying...) The problem is, I'm in an area where the protection these things provide is pretty redundant - I'd probably be fine without them. If you need them, as I said the danger is they're overwhelmed right at the start and then your kit gets damaged along with the surge protector and UPS ... Cheers. Wol
Re: [gentoo-user] console scrollback (kernel 5.14)
On Sun, Sep 26, 2021 at 6:24 PM antlists wrote: > Hello, Wol and Dale > When you rebuild it, get a surge protector and then put a UPS behind > that ... snag is that's all extra expense :-( > Surge protectors: I googled it and mostly got bad reviews. Do they _really_work? What would you recommend? It probably should be something amazon-purchasable! Availability in my country is probably limited (and overpriced to boot, I bet). UPS: never gave it serious thought, I had the impression there was too much unclear stuff: for example, is it noisy (does it need a fan)? If (when) some component needs replacement will I know it before disaster? And does the replacement require a "qualified technician"? ( Dale's description is not very reassuring!) Note that my lightning problem happened at night with both computer and monitor powered down (but still connected to a wall outlet through an interrupted extension; hence the "not-so-smart" self-qualifying...) Thanks for your suggestions Jorge
Re: [gentoo-user] console scrollback (kernel 5.14)
antlists wrote: > On 26/09/2021 13:36, Alan Mackenzie wrote: >>> Sure enough, the patch was succesful. Unfortunately, I cannot test it, >>> because my computer is out of luck (big thunderstorm, crappy power >>> provider, not-so-smart owner). > >> I'm sorry to hear it. I'm sure you've done it already, but get a decent >> backup from that machine somehow while it is still even partly working. >> > Sounds like the drive is fine, but of course the question is "for how > long? ..." > > When you rebuild it, get a surge protector and then put a UPS behind > that ... snag is that's all extra expense :-( > > Cheers, > Wol > > I agree with that advise. When I built my first system, I bought a UPS a couple months later. While most UPS's have a lot of surge protection built in, I do have additional surge protection at the wall plug and I also have a whole house surge protector in the breaker box as well. I make sure the light is green often, mostly check after a bad storm. Having protection against momentary drops in either voltage or just a outright outage for a few seconds or longer gives a lot of protection. File systems like to be unmounted and power failures are not good. Most file systems are good at recovering from problems but it does have risk. After buying a UPS and other protections, I've had very few problems that come from power issues. The biggest problem I have is the batteries in the UPS going bad and me not knowing it, even tho the UPS is supposed to alert me of that. Most computer power supplies can handle a lot but having that protection outside the computer is best. Often, it is cheaper than a computer too. If I had to pick one thing to protect my computer, it would be a UPS. It protects from most all the problems a computer can have with power. Protects against surges, brownouts and complete loss of power. Additional protection adds more protection but a UPS is a really good start. Even a small one that can only run a few minutes offers a lot. Just something to think on. Dale :-) :-) P. S. I have a CyberPower UPS. There are a lot of good brands out there tho.
Re: [gentoo-user] console scrollback (kernel 5.14)
On 26/09/2021 13:36, Alan Mackenzie wrote: Sure enough, the patch was succesful. Unfortunately, I cannot test it, because my computer is out of luck (big thunderstorm, crappy power provider, not-so-smart owner). I'm sorry to hear it. I'm sure you've done it already, but get a decent backup from that machine somehow while it is still even partly working. Sounds like the drive is fine, but of course the question is "for how long? ..." When you rebuild it, get a surge protector and then put a UPS behind that ... snag is that's all extra expense :-( Cheers, Wol
Re: [gentoo-user] console scrollback (kernel 5.14)
Hello, Jorge. On Fri, Sep 24, 2021 at 23:44:51 +, Jorge Almeida wrote: > On Fri, Sep 24, 2021 at 5:29 PM Alan Mackenzie wrote: > Hello, Alan > > > $ patch -p0 <../patch_for_5.14.diff > > > patching file ./drivers/tty/vt/vt.c > > > Hunk #1 FAILED at 3208. > > > 1 out of 1 hunk FAILED -- saving rejects to file ./drivers/tty/vt/vt.c.rej > > attached. Please start again from a gentoo-sources without any previous > > traces of the scrollback patches, and apply that patch. _Surely_ it > > should work this time. > Sure enough, the patch was succesful. Unfortunately, I cannot test it, > because my computer is out of luck (big thunderstorm, crappy power > provider, not-so-smart owner). I'm sorry to hear it. I'm sure you've done it already, but get a decent backup from that machine somehow while it is still even partly working. > I can ssh into it and it all seems fine, but VT's other than tty1 go > dim after 1 or 2 seconds (showing the greeting) and then go black; I > can login blindly! I'm sure it has nothing to do with the patch, > since I also booted the former kernel (for which the previous patch > has been applied with success as expected) and it happens the same. > Damaged UPS or MO, maybe... Anyway, I'll try again when I manage to > fix or replace the computer and I'll report then. OK, thanks! > Thanks, > Jorge Almeida > P.S. I just noticed you mention gentoo-sources. I use the vanilla > kernel from kernel.org. Could that be a problem? Highly unlikely. I doubt very much there's any difference in the tty code between vanilla and gentoo-sources, but even so, I'm now basing my patches on a Linux repository cloned from their central repository server. -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] console scrollback (kernel 5.14)
On Friday, 24 September 2021 18:29:11 BST Alan Mackenzie wrote: > To apply the patch (you surely know this already), cd to the top of the > kernel tree, and use > > $ patch -p1 < 5.14.5-scroll-20210924.diff [...] > .. Please let me know again how it works out. Thanks! Works for me, Alan, against 5.14.7. Once I spotted the change to -p1, that is. :( Thanks again. -- Regards, Peter.
Re: [gentoo-user] console scrollback (kernel 5.14)
On Fri, Sep 24, 2021 at 5:29 PM Alan Mackenzie wrote: > Hejjo, Alan > > $ patch -p0 <../patch_for_5.14.diff > > patching file ./drivers/tty/vt/vt.c > > Hunk #1 FAILED at 3208. > > 1 out of 1 hunk FAILED -- saving rejects to file ./drivers/tty/vt/vt.c.rej > > attached. Please start again from a gentoo-sources without any previous > traces of the scrollback patches, and apply that patch. _Surely_ it > should work this time. > Sure enough, the patch was succesful. Unfortunately, I cannot test it, because my computer is out of luck (big thunderstorm, crappy power provider, not-so-smart owner). I can ssh into it and it all seems fine, but VT's other than tty1 go dim after 1 or 2 seconds (showing the greeting) and then go black; I can login blindly! I'm sure it has nothing to do with the patch, since I also booted the former kernel (for which the previous patch has been applied with success as expected) and it happens the same. Damaged UPS or MO, maybe... Anyway, I'll try again when I manage to fix or replace the computer and I'll report then. Thanks, Jorge Almeida P.S. I just noticed you mention gentoo-sources. I use the vanilla kernel from kernel.org. Could that be a problem?
Re: [gentoo-user] console scrollback (kernel 5.14)
Hello, Jorge.
On Fri, Sep 24, 2021 at 09:22:45 +0100, Jorge Almeida wrote:
> On Thu, Sep 23, 2021 at 6:03 PM Alan Mackenzie wrote:
[ ]
> It still fails:
> $ patch -p0 <../patch_for_5.14.diff
> patching file ./drivers/tty/vt/vt.c
> Hunk #1 FAILED at 3208.
> 1 out of 1 hunk FAILED -- saving rejects to file ./drivers/tty/vt/vt.c.rej
Apologies once more. Late last night I managed to get a Linux kernel
git repository set up. :-) So, at least if there are any more
failures, they'll be systematic failures rather than erratic failures.
;-)
>From this I've constructed a complete clean 5.14.5 patch, which I've
attached. Please start again from a gentoo-sources without any previous
traces of the scrollback patches, and apply that patch. _Surely_ it
should work this time.
To apply the patch (you surely know this already), cd to the top of the
kernel tree, and use
$ patch -p1 < 5.14.5-scroll-20210924.diff
.. Alternatively, if you've got git, you could use
$ git apply 5.14.5-scroll-20210924.diff
.. Please let me know again how it works out. Thanks!
[ ]
> Thanks,
> Jorge Almeida
--
Alan Mackenzie (Nuremberg, Germany).
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index ef981d3b7bb4..17b51bdc9f6e 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -134,6 +134,11 @@ const struct consw *conswitchp;
#define DEFAULT_BELL_DURATION (HZ/8)
#define DEFAULT_CURSOR_BLINK_MS200
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+static unsigned int console_soft_scrollback_size =
+ 1024 * CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_SIZE;
+#endif
+
struct vc vc_cons [MAX_NR_CONSOLES];
#ifndef VT_SINGLE_DRIVER
@@ -287,7 +292,7 @@ static inline unsigned short *screenpos(const struct
vc_data *vc, int offset,
bool viewed)
{
unsigned short *p;
-
+
if (!viewed)
p = (unsigned short *)(vc->vc_origin + offset);
else if (!vc->vc_sw->con_screen_pos)
@@ -616,6 +621,218 @@ static void vc_uniscr_debug_check(struct vc_data *vc)
}
}
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+static void con_update_softback(struct vc_data *vc)
+{
+ int l = vc->vc_softback_size / vc->vc_size_row;
+ if (l > 5)
+ {
+ vc->vc_softback_end = vc->vc_softback_buf + l * vc->vc_size_row;
+ vc->vc_softback_top = vc->vc_softback_buf;
+ }
+ else
+ /* Smaller scrollback makes no sense, and 0 would screw
+ the operation totally */
+ vc->vc_softback_top = 0;
+}
+
+static int concon_set_origin(struct vc_data *vc)
+{
+ if (vc->vc_softback_lines)
+ concon_scrolldelta(vc, vc->vc_softback_lines);
+ return 0;
+}
+
+#define advance_row(p, delta) (unsigned short *)((unsigned long)(p) + (delta)
* vc->vc_size_row)
+
+static void con_redraw_softback(struct vc_data *vc, /* struct display *p, */
+ long delta)
+{
+ int count = vc->vc_rows;
+ unsigned short *d, *s;
+ unsigned long n;
+ int line = 0;
+
+ if (!vc->vc_softback_lines)
+ vc->vc_char_at_pos = scr_readw((u16 *)vc->vc_pos);
+
+ d = (u16 *) vc->vc_softback_curr;
+ if (d == (u16 *) vc->vc_softback_in)
+ d = (u16 *) vc->vc_origin;
+ n = vc->vc_softback_curr + delta * vc->vc_size_row;
+ vc->vc_softback_lines -= delta;
+ if (delta < 0) {
+ if (vc->vc_softback_curr < vc->vc_softback_top
+ && n < vc->vc_softback_buf) {
+ n += vc->vc_softback_end - vc->vc_softback_buf;
+ if (n < vc->vc_softback_top) {
+ vc->vc_softback_lines -=
+ (vc->vc_softback_top - n) / vc->vc_size_row;
+ n = vc->vc_softback_top;
+ }
+ } else if (vc->vc_softback_curr >= vc->vc_softback_top
+ && n < vc->vc_softback_top) {
+ vc->vc_softback_lines -=
+ (vc->vc_softback_top - n) / vc->vc_size_row;
+ n = vc->vc_softback_top;
+ }
+ } else {
+ if (vc->vc_softback_curr > vc->vc_softback_in
+ && n >= vc->vc_softback_end) {
+ n += vc->vc_softback_buf - vc->vc_softback_end;
+ if (n > vc->vc_softback_in) {
+ n = vc->vc_softback_in;
+ vc->vc_softback_lines = 0;
+ }
+ } else if (vc->vc_softback_curr <= vc->vc_softback_in
+ && n > vc->vc_softback_in) {
+ n = vc->vc_softback_in;
+ vc->vc_softback_lines = 0;
+ }
+ }
+ if (n == vc->vc_softback_curr)
+ return;
+ vc->vc_softback_curr = n;
+
Re: [gentoo-user] console scrollback (kernel 5.14)
On Thu, Sep 23, 2021 at 6:03 PM Alan Mackenzie wrote:
>
>
> As for the two(?) versions of my patch, they differed mainly in the
> aesthetics - diff.20210405.diff had lots of ugly maintainer comments in
> it. So, could I ask you please to try that 1-hunk patch I posted
> yesterday on top of the version you have. Please then tell me whether
> or not it works.
>
It still fails:
$ patch -p0 <../patch_for_5.14.diff
patching file ./drivers/tty/vt/vt.c
Hunk #1 FAILED at 3208.
1 out of 1 hunk FAILED -- saving rejects to file ./drivers/tty/vt/vt.c.rej
$ cat ../patch_for_5.14.diff
--- ./drivers/tty/vt/vt.c.orig 2020-12-13 22:41:30.0 +
+++ ./drivers/tty/vt/vt.c 2021-04-05 16:20:32.624563241 +
@@ -3208,6 +3208,12 @@
param.vc = vc;
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+ /* Undo any soft scrolling - and do
+ not pass through this function. */
+ concon_set_origin (vc);
+#endif
+
while (!tty->flow.stopped && count) {
int orig = *buf;
buf++;
Thanks,
Jorge Almeida
--- ./drivers/tty/vt/vt.c.orig 2020-12-13 22:41:30.0 +
+++ ./drivers/tty/vt/vt.c 2021-04-05 16:20:32.624563241 +
@@ -3208,6 +3208,12 @@
param.vc = vc;
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+ /* Undo any soft scrolling - and do
+ not pass through this function. */
+ concon_set_origin (vc);
+#endif
+
while (!tty->flow.stopped && count) {
int orig = *buf;
buf++;
Re: [gentoo-user] console scrollback (kernel 5.14)
Hello, Jorge. On Wed, Sep 22, 2021 at 22:40:11 +0100, Jorge Almeida wrote: > On Wed, Sep 22, 2021 at 9:29 PM Alan Mackenzie wrote: > Hi Alan, thanks for the reply > > I must confess that somebody told me by private email that it fails on > > systems which change their screen geometry during boot-up. For example, > > a system which first boots into 80x25, then changes to a frame buffer. > > I know why this is happening, but I don't have a machine to debug it on, > > so the debugging is happening slowly, with the help of my correspondent. > > It also doesn't seem to work on machines with kernel parameters such as > > vga=791. > OK, I don't know much about this kind of stuff, but I don't think > there's a problem there. I have an integrated GPU (intel), driver > i915, resolution 1920x1080. It boots (via Refind) with the proper > resolution, and that's it. All the VTs show the same resolution and > font. I don't use a login manager. No problems, no change is supposed > to happen. I start an X session from a login shell, in any VT except > tty1, which I like to keep as console. Sounds pretty much like my setup. :-) > > I'm assuming that the patch you tried to apply was > > 5.10.49-scroll.20210715.diff. If so, please leave it applied (with the > > one failed hunk), and additionally apply this: > I may have missed some announcement from you, I'm using > diff.20210405.diff. I wasn't aware of newer versions. Is there an URL > to download it? I would try it before trying to apply the patch > included in your message. I'm currently discovering what version control systems are for. :-( Even though I've only posted two or three versions of my patch, I'm already having difficulty keeping track of it. I no longer believe keeping the patch informally is going to work. I think I'm going to have to clone the git repository of the kernel (about which I'm going to ask on another thread). Anyhow, back to the topic. There's no URL with my patch; it's purely posted on gentoo-users. Maybe I should put it into the Gentoo wiki. But first, I must get it into a proper VCS. As for the two(?) versions of my patch, they differed mainly in the aesthetics - diff.20210405.diff had lots of ugly maintainer comments in it. So, could I ask you please to try that 1-hunk patch I posted yesterday on top of the version you have. Please then tell me whether or not it works. I am going to get this unsystematic muddle sorted out. > Thanks, > Jorge Almeida -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] console scrollback (kernel 5.14)
On Wed, Sep 22, 2021 at 9:29 PM Alan Mackenzie wrote: > > Hello, Jorge. > Hi Alan, thanks for the reply > I must confess that somebody told me by private email that it fails on > systems which change their screen geometry during boot-up. For example, > a system which first boots into 80x25, then changes to a frame buffer. > I know why this is happening, but I don't have a machine to debug it on, > so the debugging is happening slowly, with the help of my correspondent. > > It also doesn't seem to work on machines with kernel parameters such as > vga=791. OK, I don't know much about this kind of stuff, but I don't think there's a problem there. I have an integrated GPU (intel), driver i915, resolution 1920x1080. It boots (via Refind) with the proper resolution, and that's it. All the VTs show the same resolution and font. I don't use a login manager. No problems, no change is supposed to happen. I start an X session from a login shell, in any VT except tty1, which I like to keep as console. > > I'm assuming that the patch you tried to apply was > 5.10.49-scroll.20210715.diff. If so, please leave it applied (with the > one failed hunk), and additionally apply this: > I may have missed some announcement from you, I'm using diff.20210405.diff. I wasn't aware of newer versions. Is there an URL to download it? I would try it before trying to apply the patch included in your message. Thanks, Jorge Almeida
Re: [gentoo-user] console scrollback (kernel 5.14)
Hello, Jorge.
On Sat, Sep 18, 2021 at 21:40:46 +0100, Jorge Almeida wrote:
> Hello, gentooers in general and Alan in particular
> I've been using Alan Mackenzie's patch until kernel 5.13, with
> success. It failed with 5.14.4 --yes, I know, but it doesn't hurt to
> try :)
I'm happy to know my patch is still useful.
I must confess that somebody told me by private email that it fails on
systems which change their screen geometry during boot-up. For example,
a system which first boots into 80x25, then changes to a frame buffer.
I know why this is happening, but I don't have a machine to debug it on,
so the debugging is happening slowly, with the help of my correspondent.
It also doesn't seem to work on machines with kernel parameters such as
vga=791.
That said, I'm hoping that the failure of the patch on 5.14.4 is just a
simple struct change in 5.14, which I hope to have corrected (but in
5.14.5). What used to be
while (!tty->stopped ...
has now become
while (!tty->flow.stopped ...
I'm assuming that the patch you tried to apply was
5.10.49-scroll.20210715.diff. If so, please leave it applied (with the
one failed hunk), and additionally apply this:
--- ./drivers/tty/vt/vt.c.orig 2020-12-13 22:41:30.0 +
+++ ./drivers/tty/vt/vt.c 2021-04-05 16:20:32.624563241 +
@@ -3208,6 +3208,12 @@
param.vc = vc;
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+ /* Undo any soft scrolling - and do
+ not pass through this function. */
+ concon_set_origin (vc);
+#endif
+
while (!tty->flow.stopped && count) {
int orig = *buf;
buf++;
As always, there are no guarantees. Please let me know whether or not
the above hunk applies, and if so, whether or not the scrolling still
works. (Also, feel free to send me private email if there're any
problems with the mechanics of applying the patch.)
Thanks!
> Jorge Almeida
> Just in case it is useful:
It was, thanks!
[ ]
> param.vc = vc;
> + /* NEW STOUGH, 2021-04-03 */
> +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
> + /* Undo any soft scrolling - and do
> + not pass through this function. */
> + concon_set_origin (vc);
> +#endif
> + /* END OF NEW STOUGH */
> +
> while (!tty->stopped && count) { <==
> int orig = *buf;
> buf++;
--
Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback is back again!
Hello, Gentoo. A new kernel, gentoo-sources-5.10.49-r1 has become current. For those who wish to have console soft scrolling, the patch which worked with 5.10.27 actually still works in 5.10.49-r1. But I've tidied that patch up somewhat for 5.10.49-r1 and have attached the patch file to this post. The instructions for using it are basically unchanged, apart from file names, etc. Updating those instructions gives us: (i) Extract the attached patch file to your /usr/src/linux-5.10.49-gentoo-r1 directory (or probably any 5.10 kernel's). (ii) From that directory run $ patch -p0 < 5.10.49-scroll.20210715.diff. (iii)(a) If you've already got a working 5.10.49-r1, do a $ make oldconfig. That should bring up the new configuration items, for which you can accept the defaults. These two items are a flag to enable the scrollback, and a buffer size defaulting to 128kB. (iii)(b) If you haven't yet got a 5.10.49-r1, just configure your kernel in the usual way. The two new items are under Device Drivers/Graphics support/Console display driver support. (iv) Build the kernel. (v) Put the new kernel into your usual boot manager. (vi) Reboot and enjoy! As before, it works for me, and there's nothing malicious in it, but if it breaks for you, I'm sorry but I won't be responsible. -- Alan Mackenzie (Nuremberg, Germany). On Mon, Apr 05, 2021 at 17:12:07 +, Alan Mackenzie wrote: > Hello, Gentoo. > Yes, console soft scrolling is back! That essential feature that was > stripped out of the kernel at around 5.4.x has returned! > Only this time, it's even better! Instead of one scrollback buffer > shared between all tty's, there's now a buffer for each tty. > How to get it working: > (i) Extract the enclosed patch file to your /usr/src/linux-5.10.27-gentoo > directory (or probably any 5.10 kernel's). > (ii) From that directory run $ patch -p0 < diff.20210405.diff. > (iii)(a) If you've already got a working 5.10.27, do a $ make oldconfig. > That should bring up the new configuration items, for which you can > accept the defaults. These two items are a flag to enable the > scrollback, and a buffer size defaulting to 128kB. > (iii)(b) If you haven't yet got a 5.10.27, just configure your kernel in > the usual way. The two new items are under Device Drivers/Graphics > support/Console display driver support. > (iv) Build the kernel. > (v) Put the new kernel into your usual boot manager. > (vi) Reboot and enjoy! > Admittedly, the exercise isn't quite finished - the patched source files > still have my personal change markings in them, to make debugging easier. > But the problems I reported here a few days ago are now solved. One or > two features haven't (yet) been implemented - having a single scroll > buffer shared amongst all tty's isn't there, and there're no kernel > command line parameters to control the feature. > Also, you may wonder about how safe the patch is. All I can say is that > there is nothing malicious in it, and I am known on this list, but of > course if it breaks I won't be to blame. > Bug reports and other comments are welcome, of course. > If anybody would like the corresponding patch which works on 5.4.n, for n > >= 80, that is available, too. > -- > Alan Mackenzie (Nuremberg, Germany). --- ./include/linux/vt_kern.h.orig 2020-12-13 22:41:30.0 + +++ ./include/linux/vt_kern.h 2021-04-05 15:22:28.445755234 + @@ -127,6 +127,9 @@ /* vt.c */ void vt_event_post(unsigned int event, unsigned int old, unsigned int new); int vt_waitactive(int n); +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK +void concon_scrolldelta(struct vc_data *vc, int lines); +#endif void change_console(struct vc_data *new_vc); void reset_vc(struct vc_data *vc); int do_unbind_con_driver(const struct consw *csw, int first, int last, --- ./include/linux/console_struct.h.orig 2020-12-13 22:41:30.0 + +++ ./include/linux/console_struct.h2021-04-05 15:22:28.432755234 + @@ -109,6 +109,17 @@ unsigned short *vc_screenbuf; /* In-memory character/attribute buffer */ unsigned intvc_screenbuf_size; unsigned char vc_mode;/* KD_TEXT, ... */ +#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK + unsigned intvc_softback_size; /* Size in bytes of scrollback buffer. */ + unsigned long vc_softback_buf;/* Address of scrollback buffer. */ + unsigned long vc_softback_end;/* (Just past) end of buffer. */ + unsigned long vc_softback_in; /* Head pointer into circular buffer. */ + unsigned long vc_softback_top;/* Tail pointer into circular buffer. */ + unsigned long vc_softback_curr; /* Pos in vc_screenbuf or vc_softback_buf + corresponding to visible screen. */ + int vc_softback_lines; /* Number of lines currently scrolled. */ +
Re: [gentoo-user] Console scrollback is back again!
On Tue, Apr 6, 2021 at 1:12 AM Alan Mackenzie wrote: > How to get it working: > (i) Extract the enclosed patch file to your /usr/src/linux-5.10.27-gentoo > directory (or probably any 5.10 kernel's). Works with 5.10.28-gentoo. Thanks again. I finally can uninstall my 5.8.6 which still has the old scrollback. -- konsolebox
Re: [gentoo-user] Console scrollback is back again!
On Tue, Apr 6, 2021 at 4:54 AM Alan Mackenzie wrote: > Hello, Michael. > > On Mon, Apr 05, 2021 at 18:08:58 -0500, Michael Jones wrote: > > [ ] > > > Without looking at the patch itself: > > > Have you considered something like kmscon as a userland alternative? > > To be honest, no. I wasn't really aware of it when I starting working on > the Linux console. > > According to Wikipedia, the last release was in 2013, and development > stopped altogether in 2015. The Gentoo package for it is masked. > Good points, and I can't speak to the code cleanliness of kmscon, or potential security problems. That being said, even though I was annoyed when the scrollback was removed from the kernel, I do understand the reason for it being removed. It does seem like the kind of functionality that would be better provided by userspace. > > I installed it on my laptop, and aside from not working with gpmd or > > consolation for mouse support, it's a perfectly functional local tty. > > I suppose it's one of these programs that once working, pretty much > carries on working for ever. > That's entirely possible :-) Maybe someone (not necessarily you) will find the removal of the scrollback buffer to be enough motivation to bring kmscon back to life as a project.
Re: [gentoo-user] Console scrollback is back again!
Hello, John
On Tue, Apr 06, 2021 at 10:13:39 -0400, John Covici wrote:
> On Tue, 06 Apr 2021 09:14:23 -0400,
> Peter Humphrey wrote:
> > On Monday, 5 April 2021 19:13:18 BST Alan Mackenzie wrote:
> > > We'll see how people react to it here, first.
> > You're my hero!
> Would this patch work on 5.4.96 and following?
No, there is a slight difference (two struct fields moved and renamed)
between 5.4 and 5.10.
For 5.4, please use the attached patch instead. It has been tested on
5.4.80-r1 and 5.4.97.
> --
> Your life is like a penny. You're going to lose it. The question is:
> How do
> you spend it?
> John Covici wb2una
> cov...@ccs.covici.com
--
Alan Mackenzie (Nuremberg, Germany).
--- drivers/video/console/Kconfig.orig 2021-03-31 19:14:48.186140856 +
+++ drivers/video/console/Kconfig 2021-04-05 13:41:20.967713154 +
@@ -79,6 +79,55 @@
help
Low-level framebuffer-based console driver.
+config FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+ bool "Enable Scrollback Buffer in System RAM"
+ depends on FB=y && FRAMEBUFFER_CONSOLE
+ default y
+ select FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_PERSISTENT_ENABLE_BY_DEFAULT
+ help
+ This option creates scrollback buffers for each framebuffer console,
+ or one buffer for them all. These buffers are allocated dynamically
+ during initialisation.
+
+ If you want this feature, say 'Y' here and enter the amount of
+ RAM to allocate for this buffer. If unsure, say 'N'.
+
+config FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_SIZE
+ int "Scrollback Buffer Size (in KB)"
+ depends on FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+ range 1 1024
+ default "128"
+ help
+ Enter the amount of System RAM to allocate for each scrollback
+ buffer of framebuffer consoles in kilobytes. Each character
+ position on the video takes 2 bytes of storage. 128k will give you
+ approximately 4 240x67 screenfuls of scrollback buffer.
+
+config FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_PERSISTENT_ENABLE_BY_DEFAULT
+ bool "Persistent Scrollback History for each framebuffer console by
default"
+ depends on FB=y && FRAMEBUFFER_CONSOLE &&
FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+ default y
+ help
+
+ Note: this option's value N has not (?yet) been implemented (2021-04).
+
+ Say Y here if the scrollback history should persist by default when
+ switching between consoles. Otherwise, the scrollback history will
+ be flushed the first time a scroll-up operation occurs on the new
+ console after the console is switched. STOUGH!!! FIXME!!! This
+ feature can also be enabled using the boot command line parameter
+ 'vgacon.scrollback_persistent=1'.
+
+ This feature might break your tool of choice to flush the scrollback
+ buffer, e.g. clear(1) will work fine but Debian's clear_console(1)
+ will be broken, which might cause security issues.
+ You can use the escape sequence \e[3J instead if this feature is
+ activated.
+
+ Note that a buffer of VGACON_SOFT_SCROLLBACK_SIZE is taken for each
+ created tty device.
+ So if you use a RAM-constrained system, say N here.
+
config FRAMEBUFFER_CONSOLE_DETECT_PRIMARY
bool "Map the console to the primary display device"
depends on FRAMEBUFFER_CONSOLE
--- drivers/tty/vt/vt.orig.c2020-11-28 17:14:38.523649992 +
+++ drivers/tty/vt/vt.c 2021-04-05 14:33:47.743786578 +
@@ -142,6 +142,13 @@
#define DEFAULT_BELL_DURATION (HZ/8)
#define DEFAULT_CURSOR_BLINK_MS200
+/* NEW STOUGH, 2021-04-01 */
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+static unsigned int console_soft_scrollback_size =
+ 1024 * CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_SIZE;
+#endif
+/* END OF NEW STOUGH */
+
struct vc vc_cons [MAX_NR_CONSOLES];
#ifndef VT_SINGLE_DRIVER
@@ -294,7 +301,7 @@
static inline unsigned short *screenpos(struct vc_data *vc, int offset, int
viewed)
{
unsigned short *p;
-
+
if (!viewed)
p = (unsigned short *)(vc->vc_origin + offset);
else if (!vc->vc_sw->con_screen_pos)
@@ -623,6 +630,232 @@
}
}
+/* NEW STOUGH, 2021-03-31 */
+#ifdef CONFIG_FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK
+/* NEW STOUGH, 2021-04-01 */
+static void con_update_softback(struct vc_data *vc)
+{
+ int l = vc->vc_softback_size / vc->vc_size_row;
+ if (l > 5)
+ {
+ vc->vc_softback_end = vc->vc_softback_buf + l * vc->vc_size_row;
+ vc->vc_softback_top = vc->vc_softback_buf; /* STOUGH,
2021-04-04 */
+ }
+ else
+ /* Smaller scrollback makes no sense, and 0 would screw
+ the operation totally */
+ vc->vc_softback_top = 0;
+}
+
+static int concon_set_origin(struct vc_data *vc)
+{
+ if
Re: [gentoo-user] Console scrollback is back again!
On Tue, 06 Apr 2021 09:14:23 -0400, Peter Humphrey wrote: > > On Monday, 5 April 2021 19:13:18 BST Alan Mackenzie wrote: > > > We'll see how people react to it here, first. > > You're my hero! Would this patch work on 5.4.96 and following? -- Your life is like a penny. You're going to lose it. The question is: How do you spend it? John Covici wb2una cov...@ccs.covici.com
Re: [gentoo-user] Console scrollback is back again!
On Monday, 5 April 2021 19:13:18 BST Alan Mackenzie wrote: > We'll see how people react to it here, first. You're my hero! -- Regards, Peter.
Re: [gentoo-user] Console scrollback is back again!
On Monday, April 5, 2021 7:12:07 PM CEST Alan Mackenzie wrote: > Hello, Gentoo. > > Yes, console soft scrolling is back! That essential feature that was > stripped out of the kernel at around 5.4.x has returned! > > Only this time, it's even better! Instead of one scrollback buffer > shared between all tty's, there's now a buffer for each tty. > > How to get it working: > (i) Extract the enclosed patch file to your /usr/src/linux-5.10.27-gentoo > directory (or probably any 5.10 kernel's). > (ii) From that directory run $ patch -p0 < diff.20210405.diff. > (iii)(a) If you've already got a working 5.10.27, do a $ make oldconfig. > That should bring up the new configuration items, for which you can > accept the defaults. These two items are a flag to enable the > scrollback, and a buffer size defaulting to 128kB. > (iii)(b) If you haven't yet got a 5.10.27, just configure your kernel in > the usual way. The two new items are under Device Drivers/Graphics > support/Console display driver support. > (iv) Build the kernel. > (v) Put the new kernel into your usual boot manager. > (vi) Reboot and enjoy! > Thank you! I will add this to my "/etc/portage/patches/sys-kernel/gentoo-sources" directory. Right next to the gpl-defang patch.
Re: [gentoo-user] Console scrollback is back again!
Hello, Karl. On Mon, Apr 05, 2021 at 21:58:37 +0200, k...@aspodata.se wrote: > Alan Mackenzie: > > Yes, console soft scrolling is back! That essential feature that was > > stripped out of the kernel at around 5.4.x has returned! > It is commit 087b6cb17df5834d395ab72da3f937380470ba15, > between v5.4.65 and 66. > Perhaps also 0d123a8c64fde433a, cf5a7ded53652c3d63d72, and possible > other stuff. I will confess that I don't actually have a git repository of Linux on my machine. I'd have to back it up, somehow. It would be a fair amount of work to write an efficient back-up procedure - the one I have at the moment for git repos backs up the entire repository, which would probably be excessive for Linux. Currently, I've changed a mere five files, for which I'm getting by with symbolic links in the kernel tree pointing into my home directory. > > Only this time, it's even better! Instead of one scrollback buffer > > shared between all tty's, there's now a buffer for each tty. > Great, no more missing data when switching vts. > Btw, wasn't that added in commit aabd31c421ddc730edf6d89c4ed3885e4fca5e30 > but turned off by default. There was no capability at all for one buffer per tty in framebuffer consoles. It was there for VGA consoles, and, I think, one or two others. The configuration page for it was confusing - the option for "persistent scrollback" was purely for VGAcon, though that wasn't obvious. I spent time in the past trying to get multiple buffers working, and was even considering reporting a bug. > ... > > One or two features haven't (yet) been implemented - having a > > single scroll buffer shared amongst all tty's isn't there, > ... > Is there any reason to share the buffer ? Not that I can think of. The only reason might be if somebody wanted a very large scrollback buffer, but didn't have a lot of RAM. But even so, the current default takes a total of less than 1 MB of RAM with the standard 7 tty's. Even increasing the buffer size to 10 MB, that would only come to 70 MB. Such a size of buffer would really need more sophisticated handling, with search facilities, some marking of positions, and so on. That would be a large project. > > Bug reports and other comments are welcome, of course. > git log drivers/video/console/vgacon.c etc. can give some ideas > what one is up against. Once I find some way to read it. ;-( Anyhow, the patch I have is working software, and is not going away any time soon. It means I can carry on using Linux. Just in case you're interested, the problem I had with no scrolling on tty1 was due to the way the console was initialised early on in the boot process. Its structures were initialised in a separate place from the normal init function, thus bypassing the scrollbuffer's init. When it came to re-initialising it for scrollbuffer, this partial initialisation acted as a flag not to carry on with the init. At least it caused me to learn about printk. ;-) > Regards, > /Karl Hammar -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback is back again!
On Tue, Apr 6, 2021 at 10:56 AM Alan Mackenzie wrote: > > > > > I just tested it with kernel 5.11.11. Seems fine. > > Thanks! > Thank _you_! It is regrettable that console scrolling is out of the kernel. Even if one doesn't use the console that much, it is used once in a while, and those occasions tend to be precisely the ones back scrolling will be most missed. Jorge Almeida
Re: [gentoo-user] Console scrollback is back again!
Hello, Jorge. On Mon, Apr 05, 2021 at 19:38:57 +0100, Jorge Almeida wrote: > On Mon, Apr 5, 2021 at 6:12 PM Alan Mackenzie wrote: > > Hello, Gentoo. > > Yes, console soft scrolling is back! That essential feature that was > > stripped out of the kernel at around 5.4.x has returned! > > Only this time, it's even better! Instead of one scrollback buffer > > shared between all tty's, there's now a buffer for each tty. > I just tested it with kernel 5.11.11. Seems fine. Thanks! > Jorge Almeida -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback is back again!
Hello, Michael. On Mon, Apr 05, 2021 at 18:08:58 -0500, Michael Jones wrote: [ ] > Without looking at the patch itself: > Have you considered something like kmscon as a userland alternative? To be honest, no. I wasn't really aware of it when I starting working on the Linux console. According to Wikipedia, the last release was in 2013, and development stopped altogether in 2015. The Gentoo package for it is masked. > I installed it on my laptop, and aside from not working with gpmd or > consolation for mouse support, it's a perfectly functional local tty. I suppose it's one of these programs that once working, pretty much carries on working for ever. -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback is back again!
On Tue, Apr 6, 2021 at 1:12 AM Alan Mackenzie wrote: > > Hello, Gentoo. > > Yes, console soft scrolling is back! That essential feature that was > stripped out of the kernel at around 5.4.x has returned! Thank you. I'll try to make this work in 5.10.28 once it's released. -- konsolebox
Re: [gentoo-user] Console scrollback is back again!
On Mon, Apr 5, 2021, 13:13 Alan Mackenzie wrote: > Hello, Wol. > > On Mon, Apr 05, 2021 at 18:44:15 +0100, antlists wrote: > > On 05/04/2021 18:12, Alan Mackenzie wrote: > > > Bug reports and other comments are welcome, of course. > > > > > > If anybody would like the corresponding patch which works on 5.4.n, > for n > > >> = 80, that is available, too. > > > Why did it get removed from the kernel? > > Allegedly, there were security problems with it. I think the kernel > people had a program which fired random inputs at lots of components, > and noted when things went wrong; and things went wrong in the scroll > back component. And they couldn't find anybody to look into these > problems. > > That's the official position. I'm a bit more cynical about it. > > > If you want to get it back in, couldn't you ping Greg KH and get some > > help - or even just advice - getting it accepted? > > I have no reason to believe all the "security problems" will have been > resolved by my hacking. I took the algorithmic bits from 4.19.97 > basically unchanged. > > Maybe there's not much enthusiasm for this feature, in which case I will > keep it working for myself. Linux is basically unusable to me without > it. There are probably quite a few patches to restore the scrollback > floating around the web by now: the changes were not particularly > difficult to anybody who knows the code, but getting to know the code > was unusually difficult. > > We'll see how people react to it here, first. > > > Cheers, > > Wol > > -- > Alan Mackenzie (Nuremberg, Germany). Without looking at the patch itself: Have you considered something like kmscon as a userland alternative? I installed it on my laptop, and aside from not working with gpmd or consolation for mouse support, it's a perfectly functional local tty.
Re: [gentoo-user] Console scrollback is back again!
Alan Mackenzie: > Yes, console soft scrolling is back! That essential feature that was > stripped out of the kernel at around 5.4.x has returned! It is commit 087b6cb17df5834d395ab72da3f937380470ba15, between v5.4.65 and 66. Perhaps also 0d123a8c64fde433a, cf5a7ded53652c3d63d72, and possible other stuff. > Only this time, it's even better! Instead of one scrollback buffer > shared between all tty's, there's now a buffer for each tty. Great, no more missing data when switching vts. Btw, wasn't that added in commit aabd31c421ddc730edf6d89c4ed3885e4fca5e30 but turned off by default. ... > One ord two features haven't (yet) been implemented - having a > single scroll buffer shared amongst all tty's isn't there, ... Is there any reason to share the buffer ? > Bug reports and other comments are welcome, of course. git log drivers/video/console/vgacon.c etc. can give some ideas what one is up against. Regards, /Karl Hammar
Re: [gentoo-user] Console scrollback is back again!
On Mon, Apr 5, 2021 at 6:12 PM Alan Mackenzie wrote: > > Hello, Gentoo. > > Yes, console soft scrolling is back! That essential feature that was > stripped out of the kernel at around 5.4.x has returned! > > Only this time, it's even better! Instead of one scrollback buffer > shared between all tty's, there's now a buffer for each tty. > I just tested it with kernel 5.11.11. Seems fine. Jorge Almeida
Re: [gentoo-user] Console scrollback is back again!
Hello, Wol. On Mon, Apr 05, 2021 at 18:44:15 +0100, antlists wrote: > On 05/04/2021 18:12, Alan Mackenzie wrote: > > Bug reports and other comments are welcome, of course. > > > > If anybody would like the corresponding patch which works on 5.4.n, for n > >> = 80, that is available, too. > Why did it get removed from the kernel? Allegedly, there were security problems with it. I think the kernel people had a program which fired random inputs at lots of components, and noted when things went wrong; and things went wrong in the scroll back component. And they couldn't find anybody to look into these problems. That's the official position. I'm a bit more cynical about it. > If you want to get it back in, couldn't you ping Greg KH and get some > help - or even just advice - getting it accepted? I have no reason to believe all the "security problems" will have been resolved by my hacking. I took the algorithmic bits from 4.19.97 basically unchanged. Maybe there's not much enthusiasm for this feature, in which case I will keep it working for myself. Linux is basically unusable to me without it. There are probably quite a few patches to restore the scrollback floating around the web by now: the changes were not particularly difficult to anybody who knows the code, but getting to know the code was unusually difficult. We'll see how people react to it here, first. > Cheers, > Wol -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback is back again!
On 05/04/2021 18:12, Alan Mackenzie wrote: Bug reports and other comments are welcome, of course. If anybody would like the corresponding patch which works on 5.4.n, for n = 80, that is available, too. Why did it get removed from the kernel? If you want to get it back in, couldn't you ping Greg KH and get some help - or even just advice - getting it accepted? Cheers, Wol
Re: [gentoo-user] Console scrollback
Hello, Karl. Thanks for the reply. On Fri, Apr 02, 2021 at 21:32:04 +0200, k...@aspodata.se wrote: > Alan Mackenzie: > ... > > I've now cobbled together a working console scroll on Linux > > 5.4.80-gentoo-r1. In the end, I reused much of the old machinery which > > was still present in 4.19.97. Once I've tidied it up, I hope that the > > resulting patch file will apply cleanly also to later versions than > > 5.4.80-r1. > ... > Nice, where is the patch so I can try ? I've attached a patch to this post. To apply it, the following seems to work from the top directory of a kernel source tree, e.g. 5.4.80-r1: $ patch -p0 < diff.20210402.diff .. Then you'll need to run make menuconfig (or whatever), going down to Device Drivers/Graphic support/Console display driver support and there accepting the defaults for the new config variables. (This is assuming you've got FRAMEBUFFER support enabled in a neighbouring page.) Then build the kernel as normal, and put the new version into whatever boot loader you use. It should (??) run, with a scrollback buffer on each virtual terminal. Just a word about the current state of the source - it is rough, with things unfinished. The "word" STOUGH (pronounced "stuff") is just a word I use which appears nowhere else and enables me to find changes quickly and unambiguously. As I said, I'm not finished with the changes, and swapping from and back to a scrolled tty isn't completely satisfactory. Nevertheless, I hope it works for you and you have fun with it. > > (i) The scrolling doesn't work on /dev/tty1 aka the console. > > (ii) When, e.g., /dev/tty6 has been scrolled upwards a bit, and then > >pressed to go to /dev/tty2, on returning to /dev/tty6, the > > scrolling has been cancelled and the cursor is no longer visible. > > However, the scrollback buffer is still present. > > > > I think I'm fairly likely to be able to solve (ii). However, (i), the > > problem with /dev/tty1, has me baffled. I don't know where to start > > looking for the problem. If anybody with some kernel knowledge could > > make any suggestions, I'd be very grateful. > What happens if you set /dev/console to be /dev/ttyS0, i.e. make sure > that tty1 is the only one using the first virtual console. I will try than. Thanks! > Regards, > /Karl Hammar -- Alan Mackenzie (Nuremberg, Germany). --- drivers/video/console/Kconfig.orig 2021-03-31 19:14:48.186140856 + +++ drivers/video/console/Kconfig 2021-03-31 12:39:08.090301096 + @@ -79,6 +79,52 @@ help Low-level framebuffer-based console driver. +config FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK + bool "Enable Scrollback Buffer in System RAM" + depends on FB=y && FRAMEBUFFER_CONSOLE + default y + help + This option creates scrollback buffers for each framebuffer console, + or one buffer for them all. These buffers are allocated dynamically + during initialisation. + +If you want this feature, say 'Y' here and enter the amount of +RAM to allocate for this buffer. If unsure, say 'N'. + +config FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_SIZE + int "Scrollback Buffer Size (in KB)" + depends on FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK + range 1 1024 + default "128" + help + Enter the amount of System RAM to allocate for scrollback buffers of + framebuffer consoles. Each character position on the video takes 2 + bytes of storage. 128k will give you approximately 4 240x67 + screenfuls of scrollback buffer. + +config FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK_PERSISTENT_ENABLE_BY_DEFAULT + bool "Persistent Scrollback History for each framebuffer console by default" + depends on FB=y && FRAMEBUFFER_CONSOLE && FRAMEBUFFER_CONSOLE_SOFT_SCROLLBACK + default y + help + + Say Y here if the scrollback history should persist by default when + switching between consoles. Otherwise, the scrollback history will + be flushed the first time a scroll-up operation occurs on the new + console after the console is switched. STOUGH!!! FIXME!!! This + feature can also be enabled using the boot command line parameter + 'vgacon.scrollback_persistent=1'. + + This feature might break your tool of choice to flush the scrollback + buffer, e.g. clear(1) will work fine but Debian's clear_console(1) + will be broken, which might cause security issues. + You can use the escape sequence \e[3J instead if this feature is + activated. + + Note that a buffer of VGACON_SOFT_SCROLLBACK_SIZE is taken for each + created tty device. + So if you use a RAM-constrained system, say N here. + config FRAMEBUFFER_CONSOLE_DETECT_PRIMARY bool "Map the console to the primary display device" depends on FRAMEBUFFER_CONSOLE --- drivers/tty/vt/vt.orig.c2020-11-28
Re: [gentoo-user] Console scrollback
Alex Mackenzie: ... > I've now cobbled together a working console scroll on Linux > 5.4.80-gentoo-r1. In the end, I reused much of the old machinery which > was still present in 4.19.97. Once I've tidied it up, I hope that the > resulting patch file will apply cleanly also to later versions than > 5.4.80-r1. ... Nice, where is the patch so I can try ? > (i) The scrolling doesn't work on /dev/tty1 aka the console. > (ii) When, e.g., /dev/tty6 has been scrolled upwards a bit, and then >pressed to go to /dev/tty2, on returning to /dev/tty6, the > scrolling has been cancelled and the cursor is no longer visible. > However, the scrollback buffer is still present. > > I think I'm fairly likely to be able to solve (ii). However, (i), the > problem with /dev/tty1, has me baffled. I don't know where to start > looking for the problem. If anybody with some kernel knowledge could > make any suggestions, I'd be very grateful. What happens if you set /dev/console to be /dev/ttyS0, i.e. make sure that tty1 is the only one using the first virtual console. Regards, /Karl Hammar
Re: [gentoo-user] Console scrollback
Hello, Gentoo. On Wed, Jan 20, 2021 at 19:59:09 +, Alan Mackenzie wrote: [Context: Scrolling on the Linux text console using the keys and has been removed from the kernel. This is not a Good Thing.] > What I have in mind now is writing a Linux driver, a small piece of code > which would piggy-back on the existing virtual terminal drivers, and > simply pass everything through to and from the main driver, filtering out > things relevant to scrolling, and processing these in my new driver. > I've spent the last few evenings reading up on drivers, and reading the > relevant source code from 4.19.97. I can understand the kernel > maintainers not being enthusiastic about the existing code. But that > dates from, I believe, the 1990s, when RAM was measured in megabytes, and > processor speeds in megahertz. Optimisation for speed and store usage > just isn't important any more. I finally got around to looking into this seriously in the last couple of weeks. The above plan turned out not to be the right thing. I've now cobbled together a working console scroll on Linux 5.4.80-gentoo-r1. In the end, I reused much of the old machinery which was still present in 4.19.97. Once I've tidied it up, I hope that the resulting patch file will apply cleanly also to later versions than 5.4.80-r1. As a matter of interest, the kernel code for the console is not the easiest in the world to deal with, having too many abstractions and too few comments. ;-( I've enhanced the mechanism so that each tty has its own scrollback buffer, rather than one buffer being shared between all tty's. The default size of these buffers is now 128kB, but can be set in make menuconfig. I'm intending to make sharing a buffer between all tty's be an option, but haven't implemented that yet. The code, as yet, is a bit scruffy (in fact, very scruffy), and I have several technical problems: (i) The scrolling doesn't work on /dev/tty1 aka the console. (ii) When, e.g., /dev/tty6 has been scrolled upwards a bit, and then pressed to go to /dev/tty2, on returning to /dev/tty6, the scrolling has been cancelled and the cursor is no longer visible. However, the scrollback buffer is still present. I think I'm fairly likely to be able to solve (ii). However, (i), the problem with /dev/tty1, has me baffled. I don't know where to start looking for the problem. If anybody with some kernel knowledge could make any suggestions, I'd be very grateful. -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback
Hello, Wol. On Thu, Jan 21, 2021 at 09:32:13 +, Wols Lists wrote: > On 20/01/21 19:59, Alan Mackenzie wrote: > > I can understand the kernel maintainers not being enthusiastic about > > the existing code. But that dates from, I believe, the 1990s, when > > RAM was measured in megabytes, and processor speeds in megahertz. > > Optimisation for speed and store usage just isn't important any more. > I think you're being highly optimistic. Bear in mind that this is the > code that was responsible for Alan Cox ceasing linux development, it's > such a pile of steaming manure ... It is indeed a tortuous mess of code, with far too many abstractions, and far too little overview. > Don't ask me why it is, but I think it's got so much stuff wrong with it > that the entire system is marked "beware here be dragons". Over the weekend, I achieved the first part of my task, getting a transparent new driver into the kernel, which would merely pass through to and from /dev/sctty3 to and from /dev/tty3, etc. This works. Now I have to hook up with the /dev/vcs drivers to buffer the text written to the screen, so as to be able to output it again in the event of a -. I would guess I'm around 50% through the task (as in the first 50% takes the first 90% of the time, and the second 50% takes the second 90% of the time). > https://lwn.net/Articles/842415/ > Take a read, as it's mentioned in this article. The website said it would become freely available on 2021-01-28, so I'll read it then. > Cheers, > Wol -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback
On Thu, Jan 21, 2021 at 12:40 PM Remco Rijnders wrote: > > On Thu, Jan 21, 2021 at 08:58:42AM +, Jorge wrote in > : > >On Thu, Jan 21, 2021 at 8:53 AM Wols Lists wrote: > >> > > > >> https://lwn.net/Articles/842415/ > >> > >> Take a read, as it's mentioned in this article. > >> > >Paywalled... :( > > Try this link: https://lwn.net/SubscriberLink/842415/5bc3e39b4d4f52fe/ > Works. Thanks. Jorge Almeida
Re: [gentoo-user] Console scrollback
On Thu, Jan 21, 2021 at 08:58:42AM +, Jorge wrote in : On Thu, Jan 21, 2021 at 8:53 AM Wols Lists wrote: https://lwn.net/Articles/842415/ Take a read, as it's mentioned in this article. Paywalled... :( Try this link: https://lwn.net/SubscriberLink/842415/5bc3e39b4d4f52fe/
Re: [gentoo-user] Console scrollback
On Thu, Jan 21, 2021 at 8:53 AM Wols Lists wrote: > > https://lwn.net/Articles/842415/ > > Take a read, as it's mentioned in this article. > Paywalled... :( Jorge Almeida
Re: [gentoo-user] Console scrollback
On 20/01/21 19:59, Alan Mackenzie wrote: > I can understand the kernel > maintainers not being enthusiastic about the existing code. But that > dates from, I believe, the 1990s, when RAM was measured in megabytes, and > processor speeds in megahertz. Optimisation for speed and store usage > just isn't important any more. I thin you're being highly optimistic. Bear in mind that this is the code that was responsible for Alan Cox ceasing linux development, it's such a pile of steaming manure ... Don't ask me why it is, but I think it's got so much stuff wrong with it that the entire system is marked "beware here be dragons". https://lwn.net/Articles/842415/ Take a read, as it's mentioned in this article. Cheers, Wol
Re: [gentoo-user] Console scrollback
Hello, Laurence. On Tue, Jan 19, 2021 at 17:09:03 +, Laurence Perkins wrote: > On Sun, 2021-01-17 at 05:17 +, Thomas Mueller wrote: > > On Sat, 16 Jan 2021 12:01:48 +, Alan Mackenzie wrote: > > > I don't know what I'll be doing, long term. For the moment, I'll > > > be hanging onto the working kernel I've got, old though it may be > > > (4.19.97). It might be possible (I'm not sure) to hook up a user > > > space program to the keys - which would take > > > care of the scrolling. This would obviously not work with early > > > kernel messages, but would be better than nothing. I had a look at > > > the GNU screen source code yesterday to see how it managed such > > > things, but it is very sparsely commented, and thus hard work to > > > understand. Maybe I should just cut my losses, and convert to > > > using one of the BSDs. > > 2000 posts per day on Linux kernel list would be more than > > unmanageable for me! I wouldn't say "almost"! > > Is Linus Torvalds' removal of console scrolling the reason why Scroll > > Lock does not work on the console with System Rescue CD or USB, while > > with FreeBSD and NetBSD, I can press Scroll Lock and scroll back? > > I like that ability but don't think Linus Torvalds is listening or > > reading this. > > Further, with System Rescue console, the lines/text go only partway > > down. > > Using screen, now at v4.8, means having to remember a lot of key > > functions, you need a separate reference screen to look them up. > > There is also tmux, which is part of the base system in NetBSD but > > not FreeBSD. > > If Linus cared about his users, he could make the kernel headers more > > user-friendly, installing kernel headers should not be any more > > complicated than copying or downloading. > > Console scrolling is especially useful with an OS or distro that is > > built from the ground up, like Gentoo, Void or Arch, as opposed to > > being installed all at once. > > If more Linux users would go to and try NetBSD or FreeBSD, those OSes > > would have more users, more ideas, more ability to improve. > > You can even cross-compile NetBSD from Linux. You'd need NetBSD > > source tree, but don't have to do anything special to install kernel > > headers. > > Tom > You're getting this second-hand since it was my brother who actually > looked into it, so pardon anything I misremember, but the big problem > is that adding unicode support to vgacon would need a near total > rewrite, and nobody wants to do that since it's a terrible hackjob to > start with. > kmscon is slated to be the replacement. You might want to see if that > can do what you need. I looked kmscon up on Wikipedia, and apparently development ceased several years ago. What I have in mind now is writing a Linux driver, a small piece of code which would piggy-back on the existing virtual terminal drivers, and simply pass everything through to and from the main driver, filtering out things relevant to scrolling, and processing these in my new driver. I've spent the last few evenings reading up on drivers, and reading the relevant source code from 4.19.97. I can understand the kernel maintainers not being enthusiastic about the existing code. But that dates from, I believe, the 1990s, when RAM was measured in megabytes, and processor speeds in megahertz. Optimisation for speed and store usage just isn't important any more. > LMP -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback
On Sun, 2021-01-17 at 05:17 +, Thomas Mueller wrote: > On Sat, 16 Jan 2021 12:01:48 +, Alan Mackenzie wrote: > > > Hello, Gentoo. > > On Thu, Jan 14, 2021 at 16:06:38 +, Alan Mackenzie wrote: > > > On Wed, Jan 13, 2021 at 22:15:25 -, Grant Edwards wrote: > > > > On 2021-01-13, Alan Mackenzie wrote: > > > > > I think bringing up a new Gentoo system absolutely requires > > > > > working in > > > > > the console, certainly up to the point where X11 and a Window > > > > > Manager > > > > > have been installed and debugged. > > > > I usually install Gentoo via ssh. > > > > The article I read about the removal of Linux console's > > > > backscrolling > > > > feature said it was mostly due to lack of a maintainer for that > > > > code, > > > > and that if somebody stepped forward to maintain it, it could > > > > be revived. > > > I'm doing my best to step forward, but I suspect that will be > > > almost as > > > difficult as fixing the bugs in it. ;-) > > And so it transpired. I subscribed to the linux-kernel list for a > > short > > time, and offered my services in a post. Not one single reply did > > I get. > > That list is not a friendly one. It gets an almost unmanageable > > ~2000 > > posts a day, the vast bulk of which are patches, fragmented into, > > perhaps, one diff hunk per post. > > > I'm disappointed that the decision to cut out this important > > > feature was > > > taken without any serious attempt to find a maintainer. I have > > > the > > > impression (though I may be wrong), that the problem was talked > > > about on > > > the linux kernel mailing list, but nobody there took it upon > > > himself to > > > post on any of the more hard-core distributions' mailing lists, > > > such as > > > gentoo's. > > I've come to realise that Linus Torvalds, who personally took the > > decision to remove the scrolling, doesn't care about users, and > > indeed > > regards them with disdain. He cares about _customers_, and Linux's > > customers are RedHat, Suse, IBM, Intel, and the other HW > > manufacturers. > > RedHat customers don't use the console, therefore the console isn't > > important. It's a bit like Microsoft's attitude towards users. > > Sure, Linus went through the motions of pretending to try to find a > > maintainer, but didn't put any serious effort into it. He argued > > that > > "nobody" uses it anyway, therefore it is unimportant, which is an > > ironic > > echo of the argument that nobody uses Linux on a desktop PC. > > Even if the bugs came to be fixed, I doubt the scrolling would be > > allowed > > back into the kernel, for the above reasons. Exactly what the bugs > > are > > in the scrolling code wasn't gone into on the list, despite more > > than one > > contributor asking. > > > > FWOW, if you really want backscrolling on the console, you can > > > > get > > > > that with screen, but doing so would drive me nuts, since I'd > > > > have to > > > > break all my fingers to stop them from typeing ctrl-A to move > > > > the > > > > start of a line. I've switched screen's meta-character a few > > > > times, > > > > but everytime I try that I find my fingers already have > > > > something else > > > > assigned to that control character (which I had forgotten > > > > about). It > > > > would be nice if I could print out my fingers' assignment table > > > > to > > > > find an unused control character, but that doesn't seem to be > > > > how it > > > > works. > > > Can one set up a "basic" screen which doesn't use a meta- > > > character? > > I don't know what I'll be doing, long term. For the moment, I'll > > be > > hanging onto the working kernel I've got, old though it may be > > (4.19.97). > > It might be possible (I'm not sure) to hook up a user space program > > to > > the keys - which would take care of the > > scrolling. > > This would obviously not work with early kernel messages, but would > > be > > better than nothing. I had a look at the GNU screen source code > > yesterday to see how it managed such things, but it is very > > sparsely > > commented, and thus hard work to understand. > > Maybe I should just cut my losses, and convert to using one of the > > BSDs. > > 2000 posts per day on Linux kernel list would be more than > unmanageable for me! I wouldn't say "almost"! > > Is Linus Torvalds' removal of console scrolling the reason why Scroll > Lock does not work on the console with System Rescue CD or USB, while > with FreeBSD and NetBSD, I can press Scroll Lock and scroll back? > > I like that ability but don't think Linus Torvalds is listening or > reading this. > > Further, with System Rescue console, the lines/text go only partway > down. > > Using screen, now at v4.8, means having to remember a lot of key > functions, you need a separate reference screen to look them up. > > There is also tmux, which is part of the base system in NetBSD but > not FreeBSD. > > If Linus cared about his users, he could make the kernel headers more >
Re: [gentoo-user] Console scrollback
On Sat, 16 Jan 2021 12:01:48 +, Alan Mackenzie wrote: > I usually install Gentoo via ssh. > The article I read about the removal of Linux console's backscrolling > feature said it was mostly due to lack of a maintainer for that code, > and that if somebody stepped forward to maintain it, it could be revived. > I subscribed to the linux-kernel list for a short time > and offered my services in a post. Not one single reply did I get. > Linus Torvalds personally took the decision to remove the scrolling. > Sure, he went through the motions of pretending to try to find > a maintainer, but didn't put any serious effort into it. > He argued that "nobody" uses it anyway, therefore it is unimportant. > Exactly what the bugs are in the scrolling code > wasn't gone into on the list, despite more than one contributor asking. You can't expect Linus to take any time over a minority of users or for the kernel team generally to reply to someone they don't know. In order to get attention, you need to come up with a set of patches which you know work in a modified kernel in your own machine. For that, you have to put in some work of your own, searching out the bugs, examining the relevant code, finding what is needed to fix the bugs & testing patched kernels. If you try using Screen, you could print yourself a list of commands, which would make it easier to get used to its features. It may well be easier to go over to BSD instead. When I installed this system in 2015, I needed to use raw terminals, so I wonder whether this is a real problem for a lot of Gentoo users. If so, an approach by a Gentoo dev to the kernel maintainers would be likely to get the attention you can't get on your own. HTH -- ,, SUPPORT ___//___, Philip Webb ELECTRIC /] [] [] [] [] []| Cities Centre, University of Toronto TRANSIT`-O--O---' purslowatcadotinterdotnet
Re: [gentoo-user] Console scrollback
On Sat, 16 Jan 2021 12:01:48 +, Alan Mackenzie wrote: > Hello, Gentoo. > On Thu, Jan 14, 2021 at 16:06:38 +, Alan Mackenzie wrote: > > On Wed, Jan 13, 2021 at 22:15:25 -, Grant Edwards wrote: > > > On 2021-01-13, Alan Mackenzie wrote: > > > > I think bringing up a new Gentoo system absolutely requires working in > > > > the console, certainly up to the point where X11 and a Window Manager > > > > have been installed and debugged. > > > I usually install Gentoo via ssh. > > > The article I read about the removal of Linux console's backscrolling > > > feature said it was mostly due to lack of a maintainer for that code, > > > and that if somebody stepped forward to maintain it, it could be revived. > > I'm doing my best to step forward, but I suspect that will be almost as > > difficult as fixing the bugs in it. ;-) > And so it transpired. I subscribed to the linux-kernel list for a short > time, and offered my services in a post. Not one single reply did I get. > That list is not a friendly one. It gets an almost unmanageable ~2000 > posts a day, the vast bulk of which are patches, fragmented into, > perhaps, one diff hunk per post. > > I'm disappointed that the decision to cut out this important feature was > > taken without any serious attempt to find a maintainer. I have the > > impression (though I may be wrong), that the problem was talked about on > > the linux kernel mailing list, but nobody there took it upon himself to > > post on any of the more hard-core distributions' mailing lists, such as > > gentoo's. > I've come to realise that Linus Torvalds, who personally took the > decision to remove the scrolling, doesn't care about users, and indeed > regards them with disdain. He cares about _customers_, and Linux's > customers are RedHat, Suse, IBM, Intel, and the other HW manufacturers. > RedHat customers don't use the console, therefore the console isn't > important. It's a bit like Microsoft's attitude towards users. > Sure, Linus went through the motions of pretending to try to find a > maintainer, but didn't put any serious effort into it. He argued that > "nobody" uses it anyway, therefore it is unimportant, which is an ironic > echo of the argument that nobody uses Linux on a desktop PC. > Even if the bugs came to be fixed, I doubt the scrolling would be allowed > back into the kernel, for the above reasons. Exactly what the bugs are > in the scrolling code wasn't gone into on the list, despite more than one > contributor asking. > > > FWOW, if you really want backscrolling on the console, you can get > > > that with screen, but doing so would drive me nuts, since I'd have to > > > break all my fingers to stop them from typeing ctrl-A to move the > > > start of a line. I've switched screen's meta-character a few times, > > > but everytime I try that I find my fingers already have something else > > > assigned to that control character (which I had forgotten about). It > > > would be nice if I could print out my fingers' assignment table to > > > find an unused control character, but that doesn't seem to be how it > > > works. > > Can one set up a "basic" screen which doesn't use a meta-character? > I don't know what I'll be doing, long term. For the moment, I'll be > hanging onto the working kernel I've got, old though it may be (4.19.97). > It might be possible (I'm not sure) to hook up a user space program to > the keys - which would take care of the scrolling. > This would obviously not work with early kernel messages, but would be > better than nothing. I had a look at the GNU screen source code > yesterday to see how it managed such things, but it is very sparsely > commented, and thus hard work to understand. > Maybe I should just cut my losses, and convert to using one of the BSDs. 2000 posts per day on Linux kernel list would be more than unmanageable for me! I wouldn't say "almost"! Is Linus Torvalds' removal of console scrolling the reason why Scroll Lock does not work on the console with System Rescue CD or USB, while with FreeBSD and NetBSD, I can press Scroll Lock and scroll back? I like that ability but don't think Linus Torvalds is listening or reading this. Further, with System Rescue console, the lines/text go only partway down. Using screen, now at v4.8, means having to remember a lot of key functions, you need a separate reference screen to look them up. There is also tmux, which is part of the base system in NetBSD but not FreeBSD. If Linus cared about his users, he could make the kernel headers more user-friendly, installing kernel headers should not be any more complicated than copying or downloading. Console scrolling is especially useful with an OS or distro that is built from the ground up, like Gentoo, Void or Arch, as opposed to being installed all at once. If more Linux users would go to and try NetBSD or FreeBSD, those OSes would have more users, more ideas, more ability to improve. You can even
Re: [gentoo-user] Console scrollback
Grant: > On 1/13/21 2:56 PM, Alan Mackenzie wrote: ... > > Doing text work in X is s l u g g i s h. Changing from one > > application to another, which would be achieved by, say Alt-F4 on a > > console takes more key sequences in X, and is less than instantaneous. I'm using fvwm set up with 9 virtual screens and so I can swith between them with ctr-arrow, fast enought for me. ... > > On an Emacs session, in three columns on a console, I can display > > 195 consecutive lines of a source file simultaneously. ... I get 260x97 chars in emacs on a 1600x1280 display. With three columns, w82,82,83chars, I get 3x95=285 lines of text. /// Alan, how do you set up your console (I'd like to try) ? Regards, /Karl Hammar
Re: [gentoo-user] Console scrollback
Hello, Neil. On Wed, Jan 13, 2021 at 18:44:15 +, Neil Bothwick wrote: > On Wed, 13 Jan 2021 18:14:39 +, Alan Mackenzie wrote: > > > I see that the kernel code to scroll the console has been stripped out > > > [1]. > > This is appalling. I do all my work on the console (apart from web > > browsing), and with this development, Linux effectively becomes unusable > > to me. I will NOT be bullied into using second rate alternatives like > > X-Windows terminals. > What about screen/tmux? I suppose they'd do at a pinch, but they're both things which get between Linux and my applications, and like X-Windows, they offer "features" which I don't need and don't want, and hijack key sequences. But I will look into it if I have to. For the moment, I can get by by not updating my kernel. > -- > Neil Bothwick > WinErr 00D: Window closed - Do not look outside -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback
On 1/13/21 2:56 PM, Alan Mackenzie wrote: Hello, Grant. Hi Alan, Well, there's really not much that can't be done in a terminal emulator. But it's the manner of the doing that's important. Okay. I can appreciate and respect that response. Doing text work in X is s l u g g i s h. Changing from one application to another, which would be achieved by, say Alt-F4 on a console takes more key sequences in X, and is less than instantaneous. I don't know that I've ever experienced the sluggishness that you're talking about. But that doesn't mean it doesn't exist. I will admit that Alt-Tabing through windows is an additional step vs Alt-F# in that you have the intermediary list that you cycle through vs just jumping directly to the desired window. The X terminal emulator tends not to occupy the whole screen - it tends to have title bars, menu items, tabs even, which just distract from the task at hand. Maybe it can be set up to take the whole screen, but that's work. And the fonts used tend to be less distinct and helpful than the 16 x 8 bitmaps I have on the console. Those seem more like preferences / settings to me. But preferences are still sufficient to drive decisions. And X windows steals useful key sequences, such as Alt-Tab. True. On an Emacs session, in three columns on a console, I can display 195 consecutive lines of a source file simultaneously. I would expect that to be the same possibility in X and on the console. Or quite close counterparts. I could go on, but ... That's not to say there aren't problems with the tty console - even before the screen scrolling was removed altogether, it wasn't exactly anything to write home about. And it would be nice to have more than 16 colours available. But, on balance, I'll stick with the console. Fair enough. To each their own. I think bringing up a new Gentoo system absolutely requires working in the console, certainly up to the point where X11 and a Window Manager have been installed and debugged. True. Thank you Alan, for enlightening me to your work flow and how the console is better for you. -- Grant. . . . unix || die
Re: [gentoo-user] Console scrollback
Hello, Grant.
On Wed, Jan 13, 2021 at 12:32:28 -0700, Grant Taylor wrote:
> On 1/13/21 11:14 AM, Alan Mackenzie wrote:
> > This is appalling. I do all my work on the console (apart from web
> > browsing), and with this development, Linux effectively becomes
> > unusable to me. I will NOT be bullied into using second rate
> > alternatives like X-Windows terminals.
> Wow. I don't think I've run into someone that was a devout
> {physical,virtual} /console/ user in quite a while.
> I'm curious what you do in the Linux console that can't be done in a
> terminal emulator.
Well, there's really not much that can't be done in a terminal emulator.
But it's the manner of the doing that's important. Doing text work in X
is s l u g g i s h. Changing from one application to another, which
would be achieved by, say Alt-F4 on a console takes more key sequences
in X, and is less than instantaneous. The X terminal emulator tends not
to occupy the whole screen - it tends to have title bars, menu items,
tabs even, which just distract from the task at hand. Maybe it can be
set up to take the whole screen, but that's work. And the fonts used
tend to be less distinct and helpful than the 16 x 8 bitmaps I have on
the console. And X windows steals useful key sequences, such as
Alt-Tab. On an Emacs session, in three columns on a console, I can
display 195 consecutive lines of a source file simultaneously.
I could go on, but ...
That's not to say there aren't problems with the tty console - even
before the screen scrolling was removed altogether, it wasn't exactly
anything to write home about. And it would be nice to have more than 16
colours available. But, on balance, I'll stick with the console.
> I know that there is a lot of difference in different terminal
> emulators. -- I *strongly* prefer XTerm as it does things that other
> terminal emulators have never heard of.
> Please share if you do things that /can/ be done in the Linux console
> that /can't/ be done in a terminal emulator.
I think bringing up a new Gentoo system absolutely requires working in
the console, certainly up to the point where X11 and a Window Manager
have been installed and debugged.
> If it's just preference, then hat's off to you.
> --
> Grant. . . .
> unix || die
--
Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback
On 1/13/21 11:14 AM, Alan Mackenzie wrote:
This is appalling. I do all my work on the console (apart from web
browsing), and with this development, Linux effectively becomes
unusable to me. I will NOT be bullied into using second rate
alternatives like X-Windows terminals.
Wow. I don't think I've run into someone that was a devout
{physical,virtual} /console/ user in quite a while.
I'm curious what you do in the Linux console that can't be done in a
terminal emulator.
I know that there is a lot of difference in different terminal
emulators. -- I *strongly* prefer XTerm as it does things that other
terminal emulators have never heard of.
Please share if you do things that /can/ be done in the Linux console
that /can't/ be done in a terminal emulator.
If it's just preference, then hat's off to you.
--
Grant. . . .
unix || die
Re: [gentoo-user] Console scrollback
On Wednesday, 13 January 2021 18:14:39 GMT Alan Mackenzie wrote: > Hello, Peter. > > On Wed, Jan 13, 2021 at 10:30:19 +, Peter Humphrey wrote: > > Hello list, > > > > I see that the kernel code to scroll the console has been stripped out > > [1]. > > This is appalling. I do all my work on the console (apart from web > browsing), and with this development, Linux effectively becomes unusable > to me. I will NOT be bullied into using second rate alternatives like > X-Windows terminals. > > Thanks for the heads up! > > > What do people use instead? > > Well, it looks like I'll have to stop upgrading my kernel at 5.8.n. Actually, the console-scrolling code has gone from 5.4.80 too. Also 5.4.72 I think. -- Regards, Peter.
Re: [gentoo-user] Console scrollback
On Wed, 13 Jan 2021 18:14:39 +, Alan Mackenzie wrote: > > I see that the kernel code to scroll the console has been stripped out > > [1]. > > This is appalling. I do all my work on the console (apart from web > browsing), and with this development, Linux effectively becomes unusable > to me. I will NOT be bullied into using second rate alternatives like > X-Windows terminals. What about screen/tmux? -- Neil Bothwick WinErr 00D: Window closed - Do not look outside pgpHc6hSsCL0N.pgp Description: OpenPGP digital signature
Re: [gentoo-user] Console scrollback
Hello, Peter. On Wed, Jan 13, 2021 at 10:30:19 +, Peter Humphrey wrote: > Hello list, > I see that the kernel code to scroll the console has been stripped out > [1]. This is appalling. I do all my work on the console (apart from web browsing), and with this development, Linux effectively becomes unusable to me. I will NOT be bullied into using second rate alternatives like X-Windows terminals. Thanks for the heads up! > What do people use instead? Well, it looks like I'll have to stop upgrading my kernel at 5.8.n. That can only be a short term answer, though. > This loss is a nuisance while installing a new system, as I am still > trying to do on my old laptop. > 1. https://soylentnews.org/article.pl?sid=20/09/15/1824233=rss Question: I'm a C hacker; how do I go about getting to restore (and enhance) this essential facility myself? > -- > Regards, > Peter. -- Alan Mackenzie (Nuremberg, Germany).
Re: [gentoo-user] Console scrollback
On Wednesday, 13 January 2021 11:21:54 GMT Andreas Fink wrote: > How about this (works with bash, not sure about other shells): > emerge |& less > > This should work with all shells: > emerge 2>&1 | less That's better; thanks Andreas. -- Regards, Peter.
Re: [gentoo-user] Console scrollback
On Wed, 13 Jan 2021 10:55:18 + Peter Humphrey wrote: > On Wednesday, 13 January 2021 10:38:01 GMT Michael wrote: > > On Wednesday, 13 January 2021 10:30:19 GMT Peter Humphrey wrote: > > > Hello list, > > > > > > I see that the kernel code to scroll the console has been stripped out > > > [1]. What do people use instead? > > > > > > This loss is a nuisance while installing a new system, as I am still > > > trying to do on my old laptop. > > > > > > 1. https://soylentnews.org/article.pl?sid=20/09/15/1824233=rss > > > > A relief to see I'm not alone in experiencing this problem - I thought I had > > misconfigured something on my systems. :-) > > > > A way around it would be to use screen or tmux and use their internal > > buffer. However, if you're already logged in a console and suddenly want to > > Shift+PageUp, then it would be too late. This suggestion won't help if you > > want to look at the rc scripts output as the system boots, but you can > > capture these separately in syslog. > > It's a pain in the neck while trying to emerge a base system and being thrown > scores of lines of reasons why it can't be done, with the prime cause long > gone. I tried using "| tee 2>&1 > /tmp/file" and then viewing the file on > another vTTY, but there ought to be a neater way. > How about this (works with bash, not sure about other shells): emerge |& less This should work with all shells: emerge 2>&1 | less Cheers Andreas
Re: [gentoo-user] Console scrollback
On Wednesday, 13 January 2021 10:38:01 GMT Michael wrote: > On Wednesday, 13 January 2021 10:30:19 GMT Peter Humphrey wrote: > > Hello list, > > > > I see that the kernel code to scroll the console has been stripped out > > [1]. What do people use instead? > > > > This loss is a nuisance while installing a new system, as I am still > > trying to do on my old laptop. > > > > 1. https://soylentnews.org/article.pl?sid=20/09/15/1824233=rss > > A relief to see I'm not alone in experiencing this problem - I thought I had > misconfigured something on my systems. :-) > > A way around it would be to use screen or tmux and use their internal > buffer. However, if you're already logged in a console and suddenly want to > Shift+PageUp, then it would be too late. This suggestion won't help if you > want to look at the rc scripts output as the system boots, but you can > capture these separately in syslog. It's a pain in the neck while trying to emerge a base system and being thrown scores of lines of reasons why it can't be done, with the prime cause long gone. I tried using "| tee 2>&1 > /tmp/file" and then viewing the file on another vTTY, but there ought to be a neater way. -- Regards, Peter.
Re: [gentoo-user] Console scrollback
On Wednesday, 13 January 2021 10:30:19 GMT Peter Humphrey wrote: > Hello list, > > I see that the kernel code to scroll the console has been stripped out [1]. > What do people use instead? > > This loss is a nuisance while installing a new system, as I am still trying > to do on my old laptop. > > 1. https://soylentnews.org/article.pl?sid=20/09/15/1824233=rss A relief to see I'm not alone in experiencing this problem - I thought I had misconfigured something on my systems. :-) A way around it would be to use screen or tmux and use their internal buffer. However, if you're already logged in a console and suddenly want to Shift+PageUp, then it would be too late. This suggestion won't help if you want to look at the rc scripts output as the system boots, but you can capture these separately in syslog. signature.asc Description: This is a digitally signed message part.
