Re: GRUB_CMDLINE_LINUX="... memmap=8G$8G"

[John Groves]

Thanks Randy. Good info though I didn't find the a solution there.

But through the cxl developer community I have found a solution, and I'll
share it here for posterity.

    sudo grub2-editenv /boot/grub2/grubenv set memmap_val='8G\$8G'

    GRUB_CMDLINE_LINUX=" ... memmap=\$memmap_val"

Cheers,
Joh






On Thu, Dec 21, 2023 at 11:06 PM Randy Goldenberg <
randy.goldenberg@gmail.com> wrote:

> "memmap=nn[KMG]$ss[KMG]
>
>                       [KNL,ACPI] Mark specific memory as reserved.
>                       Region of memory to be reserved is from ss to ss+nn.
>                       Example: Exclude memory from 0x18690000-0x1869ffff
>                                memmap=64K$0x18690000
>                                or
>                                memmap=0x10000$0x18690000
>                       Some bootloaders may need an escape character before 
> '$',
>                       like Grub2, otherwise '$' and the following number
>                       will be eaten."
>
> https://www.kernel.org/doc/Documentation/admin-guide/kernel-parameters.txt
>
> "Changing GRUB menu entries and kernel arguments vary between Linux 
> distributions and versions of the same distro. Instructions for some of the 
> common Linux distros can be found below. Refer to the documentation of the 
> Linux distro and version being used for more information."
>
> https://docs.pmem.io/persistent-memory/getting-started-guide/creating-development-environments/linux-environments/linux-memmap
>
>