Originally posted by birdie
View Post
Announcement
Collapse
No announcement yet.
Linux Frame-Buffer Console To Drop Accelerated Scrolling Since It's Full Of Bugs
Collapse
X
-
Originally posted by Ironmask View PostQuestion: What was even the point of this code? Why would anyone care about having an accelerated terminal?
Comment
-
Originally posted by oiaohm View Post
Is the Linux kernel a single address space in kernel space. The answer is in fact no.
NUMA implementations means you really do have multi address spaces even in items like Linux kernel space..
Comment
-
Originally posted by rene View Postnot having slow like a slow as molasses terminal while a) using a computer the good old text terminal way or b) debugging some issue, e.g. Wayland or X not coming up. c) server log file scrolling? etc. or do you like slow? ;-)
This is why its one of those features I am not sure I will miss. The reality is removing accellerated scroll back and soft scrollback from kernel will in fact increase performance when you are using embedded scrollback in screen and tmux.
rene there is really chance that there is no major performance loss. Yes I understand there is going to be some annoyance with having to make some changes in workflow.
Comment
-
Originally posted by oiaohm View Post
The horrible part is is the old text based terminals did not have accelerated or soft scrollback. This is why screen, tmux and other options existed in the first place. Yes if you were using screen or tmux to do scrollback the soft or accelerated scrollback in the Linux kernel was not getting used.
This is why its one of those features I am not sure I will miss. The reality is removing accellerated scroll back and soft scrollback from kernel will in fact increase performance when you are using embedded scrollback in screen and tmux.
rene there is really chance that there is no major performance loss. Yes I understand there is going to be some annoyance with having to make some changes in workflow.
Comment
-
Originally posted by rene View PostUnclear what you think in the workqueue case, and also NUMA does not isolate different driver code. In general it is sone kernel dares space were everything can clobber each other, with off-by-one or more.
There is a long list of different protections. NUMA does at times luck end up isolating different driver code from each other inside the Linux kernel. Why it happens by luck is because the Linux kernel address space is not in fact uniform single address space.
Linux kernel in kernel space is multi address spaces because it makes sense for NUMA utilisation.
I am not saying Linux kernel space usage of the multi address spaces is ideal for security. I would say its not. Saying Linux kernel space is single address space is wrong. Correct on NUMA is is a multi address solution only by dumb luck is going to provide protection from driver to driver exploits. Since there is multi address spaces in usage due to NUMA there is the possibility that someone in future could decide to make the address assignments intentional for security reasons.
By the way a monolithic kernel is allowed to use multi page tables sets in kernel space and still be called monolithic. Lot of people think you have to be microkernel to have that.
Comment
-
Originally posted by rene View PostI remember the Linux console having scroll back for 20 years easily. Tmux is also pretty new (20 November 2007; 12 years ago) while screen had initially no scroll back and was ironically later mostly intended as virtual console user-space server for GNU Hurd (window manager for the console). Because multi-server micro kernel with everything in user-space. Amazing, right?
Yes early screen is exactly copy of a early VT100 terminal. There is no scroll back on a VT100 text terminal. Main reason why I remember when screen got scroll back was I was using VT100 terminals at the time and it was a god send to get scrollback.
I also remember when the Linux kernel got scrollback in 1993 because that was the first scrollback bug where you hold scroll back and you get kernel crash. Linux kernel console scroll back being defective has be true from day one. With this kind of history start over might be a really good idea or remove it completely.
Big thing here the screen version of scrollback for its complete 20 years has never had a stupid bug.
Yes Screen scrollback is 20 years old this year. Linux kernel scrollback feature has not made it to 20 years old.
Comment
-
Originally posted by oiaohm View Post
There is a long list of different protections. NUMA does at times luck end up isolating different driver code from each other inside the Linux kernel. Why it happens by luck is because the Linux kernel address space is not in fact uniform single address space.
Linux kernel in kernel space is multi address spaces because it makes sense for NUMA utilisation.
I am not saying Linux kernel space usage of the multi address spaces is ideal for security. I would say its not. Saying Linux kernel space is single address space is wrong. Correct on NUMA is is a multi address solution only by dumb luck is going to provide protection from driver to driver exploits. Since there is multi address spaces in usage due to NUMA there is the possibility that someone in future could decide to make the address assignments intentional for security reasons.
By the way a monolithic kernel is allowed to use multi page tables sets in kernel space and still be called monolithic. Lot of people think you have to be microkernel to have that.
Comment
-
Originally posted by oiaohm View Post
Screen gets scroll back in 1990 Linux does not get scrollback in it console until 1993.
Yes early screen is exactly copy of a early VT100 terminal. There is no scroll back on a VT100 text terminal. Main reason why I remember when screen got scroll back was I was using VT100 terminals at the time and it was a god send to get scrollback.
I also remember when the Linux kernel got scrollback in 1993 because that was the first scrollback bug where you hold scroll back and you get kernel crash. Linux kernel console scroll back being defective has be true from day one. With this kind of history start over might be a really good idea or remove it completely.
Big thing here the screen version of scrollback for its complete 20 years has never had a stupid bug.
Yes Screen scrollback is 20 years old this year. Linux kernel scrollback feature has not made it to 20 years old.
Comment
Comment