From: Masayoshi Mizuma <m.miz...@jp.fujitsu.com> This kernel parameter allows to change 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 <m.miz...@jp.fujitsu.com> --- .../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 92eb1f4..4c4c5e6 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. + + This parameter is useful for the memory hot-add capable + system. Such system may have more space than + actual memory size to hot-add memory. If the + padding size is not enough and a memory is hot-added, + the hot-adding will fail because it destroys the + system memory map. So, the padding size is needed to + adjust in such system. + The default value is + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING. + ras=option[,option,...] [KNL] RAS-specific options cec_disable [X86] -- 2.18.0