Commit-ID: 2d580c160ada91049fc24b244ed74d8775bd1c96 Gitweb: https://git.kernel.org/tip/2d580c160ada91049fc24b244ed74d8775bd1c96 Author: Masayoshi Mizuma <[email protected]> AuthorDate: Mon, 1 Oct 2018 10:08:43 -0400 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 2 Oct 2018 11:47:22 +0200
Documentation/kernel-parameters.txt: Document rand_mem_physical_padding= This kernel parameter allows the modification of the padding used for the physical memory mapping section when KASLR memory is enabled. For memory hotplug capable systems, the default padding size, CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING, may not be enough. The option is useful to adjust the padding size. Signed-off-by: Masayoshi Mizuma <[email protected]> Cc: Baoquan He <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Masayoshi Mizuma <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- Documentation/admin-guide/kernel-parameters.txt | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 64a3bf54b974..45f614cd2a61 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3529,6 +3529,24 @@ fully seed the kernel's CRNG. Default is controlled by CONFIG_RANDOM_TRUST_CPU. + rand_mem_physical_padding= + [KNL] Define the padding size in terabytes + used for the physical memory mapping section + when KASLR is enabled. + If the padding size is not enough, you can see + 'Set rand_mem_physical_padding=XX ...' in system + boot message, so set the parameter as the message suggests. + + This parameter is useful for memory hot-add capable + systems. Such systems may have more space than + actual memory size to hot-add memory. If the + padding size is not enough and memory is hot-added, + the hot-adding will fail because it destroys the + system memory map. So, the padding size needs to be + adjusted in such a system. + The default value is the value of + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING. + ras=option[,option,...] [KNL] RAS-specific options cec_disable [X86]
