A weak point in ubuntu 20.04

[gamo]

Hi there!

The problem is that when I copy from a web page (ff) and
try to paste in... LO or jed or... the paste option is over.
The 'clipboard' was deleted in the change of programs.
How do you solve that or avoid that???

Best.

[Mike Easter]

Post by gamo
The problem is that when I copy from a web page (ff) and
try to paste in... LO or jed or... the paste option is over.
The 'clipboard' was deleted in the change of programs.
How do you solve that or avoid that???

I don't understand what you mean. Ub 20.04 has a 'conventional' clipboard.

However, some webpages don't easily lend themselves to be copied and
might require some kind of 'alternate' view of the text to copy it.

Do you have some specific page in mind?

[gamo]

Post by gamo
The problem is that when I copy from a web page (ff) and
try to paste in... LO or jed or... the paste option is over.
The 'clipboard' was deleted in the change of programs.
How do you solve that or avoid that???

I don't understand what you mean.  Ub 20.04 has a 'conventional' clipboard.
However, some webpages don't easily lend themselves to be copied and
might require some kind of 'alternate' view of the text to copy it.
Do you have some specific page in mind?

https://en.wikiquote.org/wiki/Cynicism

[Mike Easter]

Post by gamo

Post by Mike Easter

Post by gamo
The problem is that when I copy from a web page (ff) and
try to paste in... LO or jed or... the paste option is over.
The 'clipboard' was deleted in the change of programs.
How do you solve that or avoid that???

Do you have some specific page in mind?

https://en.wikiquote.org/wiki/Cynicism

That page text copies just fine for pasting from the clipboard.

In Ffx I also sometimes use the Reader view or View/ Page style/ No
style for some things I do.

[Dirk T. Verbeek]

It sounds to me like a problem with Firefox.
This is a section from Slashdot:
---------------
From the Department of Justice announcement:

The ransomware informed victims that their computer was encrypted, and
that they would need to purchase special software through a Bitcoin
address controlled by the Trickbot Group to decrypt their files. In
addition, Witte allegedly provided code to the Trickbot Group that
monitored and tracked authorized users of the malware and developed
tools and protocols to store stolen login credentials... Witte and her
co-conspirators allegedly worked together to infect victim computers
with the Trickbot malware designed to capture online banking login
credentials and harvest other personal information, including credit
card numbers, emails, passwords, dates of birth, social security numbers
and addresses. Witte and others also allegedly captured login
credentials and other stolen personal information to gain access to
online bank accounts, execute unauthorized electronic funds transfers
and launder the money through U.S. and foreign beneficiary accounts...
---------------

The markup is not copied as usenet should not contain html
Anything fancier would require PrtSc.

In LO I also get the correct fonts.

Post by gamo
Hi there!
The problem is that when I copy from a web page (ff) and
try to paste in... LO or jed or... the paste option is over.
The 'clipboard' was deleted in the change of programs.
How do you solve that or avoid that???
Best.

[gamo]

Post by Dirk T. Verbeek
It sounds to me like a problem with Firefox.
---------------
The ransomware informed victims that their computer was encrypted, and
that they would need to purchase special software through a Bitcoin
address controlled by the Trickbot Group to decrypt their files. In
addition, Witte allegedly provided code to the Trickbot Group that
monitored and tracked authorized users of the malware and developed
tools and protocols to store stolen login credentials... Witte and her
co-conspirators allegedly worked together to infect victim computers
with the Trickbot malware designed to capture online banking login
credentials and harvest other personal information, including credit
card numbers, emails, passwords, dates of birth, social security numbers
and addresses. Witte and others also allegedly captured login
credentials and other stolen personal information to gain access to
online bank accounts, execute unauthorized electronic funds transfers
and launder the money through U.S. and foreign beneficiary accounts...
---------------
The markup is not copied as usenet should not contain html
Anything fancier would require PrtSc.
In LO I also get the correct fonts.

Thanks. Related to this displeasant info,
could I boot the computer without the memtest+ program?

[Mike Easter]

Post by gamo
could I boot the computer without the memtest+ program?

What do you mean?

Are you perhaps talking about the default file system check that
requires a ctrl-C to abort? The memtest function at boot is not
automatic but an option in the boot menu. Are you talking about
something in grub?

[Mike Easter]

Post by gamo
could I boot the computer without the memtest+ program?

I booted a live Ub 20.04.1 Mate. I see that it has memtest86+ installed

Post by gamo
This tester runs independently of any OS - it is run at computer
boot-up, so that it can test *all* of your memory. You may want to
look at `memtester', which allows to test your memory within Linux,
but this one won't be able to test your whole RAM.

I'm not sure I follow/understand the full meaning of that description.

[Aragorn]

Post by Mike Easter

Post by gamo
could I boot the computer without the memtest+ program?

I booted a live Ub 20.04.1 Mate. I see that it has memtest86+

Post by gamo
This tester runs independently of any OS - it is run at computer
boot-up, so that it can test *all* of your memory. You may want to
look at `memtester', which allows to test your memory within Linux,
but this one won't be able to test your whole RAM.

I'm not sure I follow/understand the full meaning of that description.

The program called memtester runs as a process in an already running
OS, and therefore it cannot access all of your RAM. Only the kernel
can do that.

memtest86+ is in essence a kernel. It boots as a kernel specifically
geared towards testing the RAM. It does not run on top of anything but
the hardware, and there isn't anything else running alongside it
either. Therefore, given that it runs as a kernel — in ring 0 of the
processor core — it can access and scan all of the available RAM
without any interference or limitation by the memory page protection.
It essentially uses your entire RAM as a single address space.

[Mike Easter]

Post by Aragorn
The program called memtester runs as a process in an already running
OS, and therefore it cannot access all of your RAM. Only the kernel
can do that.
memtest86+ is in essence a kernel. It boots as a kernel specifically
geared towards testing the RAM. It does not run on top of anything but
the hardware, and there isn't anything else running alongside it
either. Therefore, given that it runs as a kernel — in ring 0 of the
processor core — it can access and scan all of the available RAM
without any interference or limitation by the memory page protection.
It essentially uses your entire RAM as a single address space.

But...

re gamo's query; I don't know of any memtest that runs by default when
Ub 20.04 is booted, live, VM, or installed. In order to do a memtest
'at boot' (ie prior to boot) one has to enable that option.

Post by Aragorn
could I boot the computer without the memtest+ program?

... as the 'without' simply meaning 'uninstall a program which is
installed by default, but which does NOT run by default at boot'.

[Aragorn]

Post by Mike Easter

Post by Aragorn
The program called memtester runs as a process in an already running
OS, and therefore it cannot access all of your RAM. Only the kernel
can do that.
memtest86+ is in essence a kernel. It boots as a kernel
specifically geared towards testing the RAM. It does not run on
top of anything but the hardware, and there isn't anything else
running alongside it either. Therefore, given that it runs as a
kernel — in ring 0 of the processor core — it can access and scan
all of the available RAM without any interference or limitation by
the memory page protection. It essentially uses your entire RAM as
a single address space.

But...
re gamo's query; I don't know of any memtest that runs by default
when Ub 20.04 is booted, live, VM, or installed. In order to do a
memtest 'at boot' (ie prior to boot) one has to enable that option.

Post by Aragorn
could I boot the computer without the memtest+ program?

... as the 'without' simply meaning 'uninstall a program which is
installed by default, but which does NOT run by default at boot'.

To tell you the truth, his question didn't make any sense to me
personally either.

However, GRUB can remember the last-booted entry and use that as the
default choice upon the next boot. I don't know whether Ubuntu
configures GRUB that way out-of-the-box, but Manjaro and Arch do.

If Ubuntu does that too, then it's possible that gamo's GRUB has stored
memtest86+ as the default boot choice because he ran it once before.
And then all he needs to do is boot another entry, and then that should
become the default for the following boot.

Of course, there's always the option of editing /etc/default/grub and
disabling the option to save the last boot choice and make it the
default, possibly even by hard-defining a default entry in the file.

1. Change...

GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true

... into

GRUB_DEFAULT=a-number-here
GRUB_SAVEDEFAULT=false

... whereby "a-number-here" corresponds to the number of the
preferred default choice, starting from number "0" for the first
entry.

2. Run the command...

$ sudo update-grub

[Paul]

Post by Mike Easter

Post by Aragorn
The program called memtester runs as a process in an already running
OS, and therefore it cannot access all of your RAM. Only the kernel
can do that.
memtest86+ is in essence a kernel. It boots as a kernel specifically
geared towards testing the RAM. It does not run on top of anything but
the hardware, and there isn't anything else running alongside it
either. Therefore, given that it runs as a kernel — in ring 0 of the
processor core — it can access and scan all of the available RAM
without any interference or limitation by the memory page protection.
It essentially uses your entire RAM as a single address space.

But...
re gamo's query; I don't know of any memtest that runs by default when
Ub 20.04 is booted, live, VM, or installed. In order to do a memtest
'at boot' (ie prior to boot) one has to enable that option.

Post by Aragorn
could I boot the computer without the memtest+ program?

... as the 'without' simply meaning 'uninstall a program which is
installed by default, but which does NOT run by default at boot'.

memtest+ is mutually exclusive of the kernel/OS booting.

Nothing else runs while memtest runs.

The memtest executable is small, and is the sole executable
running at the time of the test. There is no tradition Linus Torvalds
kernel or scheduler.

Thus, the only impact of having a memtest+ capability, is
an extra line somewhere in a boot menu choice. That's the
only impact, a trivial cosmetic impact. It's not using
resources.

Paul

[Paul]

Post by Mike Easter

Post by gamo
could I boot the computer without the memtest+ program?

I booted a live Ub 20.04.1 Mate. I see that it has memtest86+ installed

Post by gamo
This tester runs independently of any OS - it is run at computer
boot-up, so that it can test *all* of your memory. You may want to
look at `memtester', which allows to test your memory within Linux,
but this one won't be able to test your whole RAM.

I'm not sure I follow/understand the full meaning of that description.

Running a memory tester in Linux, while the kernel runs.

+-----------+
| Test-able | \
| | \
| | \
| | /
| | /
+-----------+ /
| Kernel |
| |
| |
+-----------+
| BIOS E810 |
+-----------+

Running a memory tester as a bootable binary.

+-----------+
| Test-able | \
| | \
| | \
| | \
| | |--- Mostly testable
| | /
| | /
| | /
| code | /
+-----------+
| BIOS E810 | 1MB not covered
+-----------+

Note: The "code" hunk is moved out of the way,
and the memory tester tests the area the code
used to occupy. Later, the code is moved back.
This means the "code load" area is tested!

The BIOS E810 area is reserved for BIOS usage. If
memtest were to work in there, all hell would break loose.
This is one area that cannot be massaged with "move it out
of the way" code. The machine can take an SMI for
SMM (system management mode) at any time, while the
memory test code is running. On an Asus motherboard,
this could happen 30 times a second while the VCore
phases are adjusted.

*******

How to *really* test memory 100%.

It requires a four slot motherboard and two DIMMs.
The "X" equals no DIMM. You put the two DIMMs on
the same channel (single channel mode).

Channel 0 Channel 1
High X
Low X

If the test passes, you swap the DIMMs

Channel 0 Channel 1
Low X
High X

This solves the 1MB area at the bottom, but may
not cover a few other spots. I would have to find
an E810 description to get an exact inventory.

I've only had one case, where the memory was bad
in a "critical" location. Most other times, random
chance favors the system coming up.

I've had one chip on a DIMM fail and generate random
byte values (likely the bus is floating). This means
there are failure patterns other than a single
stuck-at bit somewhere. Using the above single-channel
test mode, one test case would not boot memtest, while
the other would. The errors were just scrolling off
the screen... :-) That was some Crucial Ballistix.

Paul