| From f05e79a0143beb2d9a482a3ebf4fe0ce76778122 Mon Sep 17 00:00:00 2001 |
| From: Javier Martinez Canillas <javierm@redhat.com> |
| Date: Sat, 7 Nov 2020 01:03:18 +0100 |
| Subject: [PATCH] docs: Document the cutmem command |
| |
| The command is not present in the docs/grub.texi user documentation. |
| |
| Reported-by: Daniel Kiper <daniel.kiper@oracle.com> |
| Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> |
| Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com> |
| Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> |
| Signed-off-by: Stefan SΓΈrensen <stefan.sorensen@spectralink.com> |
| --- |
| docs/grub.texi | 21 +++++++++++++++++++++ |
| 1 file changed, 21 insertions(+) |
| |
| diff --git a/docs/grub.texi b/docs/grub.texi |
| index 79f58c5..8518cc0 100644 |
| --- a/docs/grub.texi |
| +++ b/docs/grub.texi |
| @@ -3892,6 +3892,7 @@ you forget a command, you can run the command @command{help} |
| * cpuid:: Check for CPU features |
| * crc:: Compute or check CRC32 checksums |
| * cryptomount:: Mount a crypto device |
| +* cutmem:: Remove memory regions |
| * date:: Display or set current date and time |
| * devicetree:: Load a device tree blob |
| * distrust:: Remove a pubkey from trusted keys |
| @@ -4051,6 +4052,8 @@ this page is to be filtered. This syntax makes it easy to represent patterns |
| that are often result of memory damage, due to physical distribution of memory |
| cells. |
| |
| +The command is similar to @command{cutmem} command. |
| + |
| Note: The command is not allowed when lockdown is enforced (@pxref{Lockdown}). |
| This prevents removing EFI memory regions to potentially subvert the |
| security mechanisms provided by the UEFI secure boot. |
| @@ -4214,6 +4217,24 @@ GRUB suports devices encrypted using LUKS and geli. Note that necessary modules |
| be used. |
| @end deffn |
| |
| +@node cutmem |
| +@subsection cutmem |
| + |
| +@deffn Command cutmem from[K|M|G] to[K|M|G] |
| +Remove any memory regions in specified range. |
| +@end deffn |
| + |
| +This command notifies the memory manager that specified regions of RAM ought to |
| +be filtered out. This remains in effect after a payload kernel has been loaded |
| +by GRUB, as long as the loaded kernel obtains its memory map from GRUB. Kernels |
| +that support this include Linux, GNU Mach, the kernel of FreeBSD and Multiboot |
| +kernels in general. |
| + |
| +The command is similar to @command{badram} command. |
| + |
| +Note: The command is not allowed when lockdown is enforced (@pxref{Lockdown}). |
| + This prevents removing EFI memory regions to potentially subvert the |
| + security mechanisms provided by the UEFI secure boot. |
| |
| @node date |
| @subsection date |
| -- |
| 2.14.2 |
| |