1*4882a593SmuzhiyunFrom f05e79a0143beb2d9a482a3ebf4fe0ce76778122 Mon Sep 17 00:00:00 2001 2*4882a593SmuzhiyunFrom: Javier Martinez Canillas <javierm@redhat.com> 3*4882a593SmuzhiyunDate: Sat, 7 Nov 2020 01:03:18 +0100 4*4882a593SmuzhiyunSubject: [PATCH] docs: Document the cutmem command 5*4882a593Smuzhiyun 6*4882a593SmuzhiyunThe command is not present in the docs/grub.texi user documentation. 7*4882a593Smuzhiyun 8*4882a593SmuzhiyunReported-by: Daniel Kiper <daniel.kiper@oracle.com> 9*4882a593SmuzhiyunSigned-off-by: Javier Martinez Canillas <javierm@redhat.com> 10*4882a593SmuzhiyunSigned-off-by: Daniel Kiper <daniel.kiper@oracle.com> 11*4882a593SmuzhiyunReviewed-by: Javier Martinez Canillas <javierm@redhat.com> 12*4882a593SmuzhiyunSigned-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com> 13*4882a593Smuzhiyun--- 14*4882a593Smuzhiyun docs/grub.texi | 21 +++++++++++++++++++++ 15*4882a593Smuzhiyun 1 file changed, 21 insertions(+) 16*4882a593Smuzhiyun 17*4882a593Smuzhiyundiff --git a/docs/grub.texi b/docs/grub.texi 18*4882a593Smuzhiyunindex 79f58c5..8518cc0 100644 19*4882a593Smuzhiyun--- a/docs/grub.texi 20*4882a593Smuzhiyun+++ b/docs/grub.texi 21*4882a593Smuzhiyun@@ -3892,6 +3892,7 @@ you forget a command, you can run the command @command{help} 22*4882a593Smuzhiyun * cpuid:: Check for CPU features 23*4882a593Smuzhiyun * crc:: Compute or check CRC32 checksums 24*4882a593Smuzhiyun * cryptomount:: Mount a crypto device 25*4882a593Smuzhiyun+* cutmem:: Remove memory regions 26*4882a593Smuzhiyun * date:: Display or set current date and time 27*4882a593Smuzhiyun * devicetree:: Load a device tree blob 28*4882a593Smuzhiyun * distrust:: Remove a pubkey from trusted keys 29*4882a593Smuzhiyun@@ -4051,6 +4052,8 @@ this page is to be filtered. This syntax makes it easy to represent patterns 30*4882a593Smuzhiyun that are often result of memory damage, due to physical distribution of memory 31*4882a593Smuzhiyun cells. 32*4882a593Smuzhiyun 33*4882a593Smuzhiyun+The command is similar to @command{cutmem} command. 34*4882a593Smuzhiyun+ 35*4882a593Smuzhiyun Note: The command is not allowed when lockdown is enforced (@pxref{Lockdown}). 36*4882a593Smuzhiyun This prevents removing EFI memory regions to potentially subvert the 37*4882a593Smuzhiyun security mechanisms provided by the UEFI secure boot. 38*4882a593Smuzhiyun@@ -4214,6 +4217,24 @@ GRUB suports devices encrypted using LUKS and geli. Note that necessary modules 39*4882a593Smuzhiyun be used. 40*4882a593Smuzhiyun @end deffn 41*4882a593Smuzhiyun 42*4882a593Smuzhiyun+@node cutmem 43*4882a593Smuzhiyun+@subsection cutmem 44*4882a593Smuzhiyun+ 45*4882a593Smuzhiyun+@deffn Command cutmem from[K|M|G] to[K|M|G] 46*4882a593Smuzhiyun+Remove any memory regions in specified range. 47*4882a593Smuzhiyun+@end deffn 48*4882a593Smuzhiyun+ 49*4882a593Smuzhiyun+This command notifies the memory manager that specified regions of RAM ought to 50*4882a593Smuzhiyun+be filtered out. This remains in effect after a payload kernel has been loaded 51*4882a593Smuzhiyun+by GRUB, as long as the loaded kernel obtains its memory map from GRUB. Kernels 52*4882a593Smuzhiyun+that support this include Linux, GNU Mach, the kernel of FreeBSD and Multiboot 53*4882a593Smuzhiyun+kernels in general. 54*4882a593Smuzhiyun+ 55*4882a593Smuzhiyun+The command is similar to @command{badram} command. 56*4882a593Smuzhiyun+ 57*4882a593Smuzhiyun+Note: The command is not allowed when lockdown is enforced (@pxref{Lockdown}). 58*4882a593Smuzhiyun+ This prevents removing EFI memory regions to potentially subvert the 59*4882a593Smuzhiyun+ security mechanisms provided by the UEFI secure boot. 60*4882a593Smuzhiyun 61*4882a593Smuzhiyun @node date 62*4882a593Smuzhiyun @subsection date 63*4882a593Smuzhiyun-- 64*4882a593Smuzhiyun2.14.2 65*4882a593Smuzhiyun 66