On Thu, Sep 27, 2018 at 11:17:47PM +0200, Borislav Petkov wrote: > On Thu, Sep 27, 2018 at 04:31:46PM -0400, Masayoshi Mizuma wrote: > > 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> > > --- > > Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ > > 1 file changed, 7 insertions(+) > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt > > b/Documentation/admin-guide/kernel-parameters.txt > > index 92eb1f4..de43cdf 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -3529,6 +3529,13 @@ > > 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 memory is enabled. > > + The default value is > > + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING. > > Yet another kernel parameter which forces me to go look at what the > code does because this help text doesn't really help. And I see that in > previous iterations ok lkml it was *actually* properly explained why > this parameter is needed. > > So please summarize that explanation here so that the user can make an > informed decision when reading this help text. Always think of explaning > this to a colleague of yours who doesn't know about the memory padding > and memory hotadd problematic and try to write it in such a way so that > your colleague understands it. > > :-)
You are right, I didn't make it clear enough... Thank you for your comments, I'll fix the description. Thanks! Masa
