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| author | Jan H. Schönherr <jschoenh@amazon.de> | 2018-02-03 00:10:20 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-26 08:44:52 +0100 |
| commit | ef61f8a340fd6d49df6b367785743febc47320c1 (patch) | |
| tree | 010e1943bd46fcc03e8d5ddb638c0e81254a9a5b /Documentation | |
| parent | 672c0ae09b33a11d8f31fc61526632e96301164c (diff) | |
x86/boot/e820: Implement a range manipulation operator
Add a more versatile memmap= operator, which -- in addition to all the
things that were possible before -- allows you to:
- redeclare existing ranges -- before, you were limited to adding ranges;
- drop any range -- like a mem= for any location;
- use any e820 memory type -- not just some predefined ones.
The syntax is:
memmap=<size>%<offset>-<oldtype>+<newtype>
Size and offset work as usual. The "-<oldtype>" and "+<newtype>" are
optional and their existence determine the behavior: The command
works on the specified range of memory limited to type <oldtype>
(if specified). This memory is then configured to show up as <newtype>.
If <newtype> is not specified, the memory is removed from the e820 map.
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180202231020.15608-1-jschoenh@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 1d1d53f85ddd..5529fa82700b 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2237,6 +2237,15 @@ The memory region may be marked as e820 type 12 (0xc) and is NVDIMM or ADR memory. + memmap=<size>%<offset>-<oldtype>+<newtype> + [KNL,ACPI] Convert memory within the specified region + from <oldtype> to <newtype>. If "-<oldtype>" is left + out, the whole region will be marked as <newtype>, + even if previously unavailable. If "+<newtype>" is left + out, matching memory will be removed. Types are + specified as e820 types, e.g., 1 = RAM, 2 = reserved, + 3 = ACPI, 12 = PRAM. + memory_corruption_check=0/1 [X86] Some BIOSes seem to corrupt the first 64k of memory when doing things like suspend/resume. |