Re: Grub saved my Laptop, and made it usable. so i wanted to say thanks to everybody that worked on it.

[Project Development]

On Mon, Nov 7, 2022 at 9:50 AM James Wabi <imitomx1978@gmail.com> wrote:
>
> Thanks vladimir, sadly it did not work. What i did was to include the memmap 
> line like this on boot/grub/grub.cfg
>
>
> # This Menu entry brought to you courtesy of 
> https://www.pendrivelinux.com/install-grub2-on-usb-from-ubuntu-linux/
> set timeout=10
> set default=0
>
> menuentry "Run Ubuntu Live ISO" {
>  loopback loop /ubuntu.iso
>  linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/ubuntu.iso splash 
> -- 
> memmap=16K\\\$0x0000000B4018000,16K\\\$0x0000000B2018000,4K\\\$0x0000000B401C000,4K\\\$0x0000000B201C000

I bet your problem here is one too many levels of escaping being done. Try:

  linux (loop)/casper/vmlinuz boot=casper
iso-scan/filename=/ubuntu.iso splash --
memmap=16K\$0x0000000B4018000,16K\$0x0000000B2018000,4K\$0x0000000B401C000,4K\$0x0000000B201C000

A little more generic, and not linux specific way would be to use
GRUB's cutmem command[1]. Based on the documentation, I think you
could have the following lines at the top of the grub config:

 cutmem 2949216K 2949232K
 cutmem 2916448K 2916464K
 cutmem 2949232K 2949236K
 cutmem 2916464K 2916468K

Glenn

[1] https://www.gnu.org/software/grub/manual/grub/html_node/cutmem.html

>
>  initrd (loop)/casper/initrd
> }
>
> Then i booted ubuntu from live usb, and i wanted to double check if those 
> areas in the memory were reserved. So i opened terminal, and executed :  dmesg
> A long list of reserved things were displayed but nothing related to those 
> specific memory addresses.
>
> regards!