Subject: Re: [PATCH v6 1/5] kaslr: add kaslr_mem=nn[KMG]@ss[KMG] to specify
 extracting memory
To: Chao Fan <fanc.fnst@cn.fujitsu.com>, linux-kernel@vger.kernel.org,
        x86@kernel.org, hpa@zytor.com, tglx@linutronix.de,
        mingo@redhat.com, bhe@redhat.com, keescook@chromium.org,
        yasu.isimatu@gmail.com
Cc: indou.takao@jp.fujitsu.com, lcapitulino@redhat.com
References: <20180115124016.17683-1-fanc.fnst@cn.fujitsu.com>
 <20180115124016.17683-2-fanc.fnst@cn.fujitsu.com>
From: Randy Dunlap <rdunlap@infradead.org>
Message-ID: <5caa647b-22cb-6b77-eb4c-bd0ef1f70b7f@infradead.org>
Date: Mon, 15 Jan 2018 14:40:35 -0800
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On 01/15/2018 04:40 AM, Chao Fan wrote:
> In current code, kaslr only has a method to avoid some memory regions,
> but no method to specify the regions for kaslr to extract. So kaslr
> may choose the wrong position sometimes, which will cause some other
> features fail.
> 
> Here is a problem that kaslr may choose the memory region in movable
> nodes to extract kernel, which will make the nodes can't be hot-removed.
> To solve it, we can specify the memory region in immovable node.
> Create "kaslr_mem=" to store the regions in immovable nodes, where should
> be chosen by kaslr.
> 
> Also change the "handle_mem_memmap" to "handle_mem_filter", since
> it will not only handle memmap parameter now.

Hi,

Are any of the kernel command-line parameters documented anywhere?

Thanks.

> Multiple regions can be specified, comma delimited.
> Considering the usage of memory, only support for 4 regions.
> 4 regions contains 2 nodes at least, enough for kernel to extract.
> 
> Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
> ---
>  arch/x86/boot/compressed/kaslr.c | 73 ++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 70 insertions(+), 3 deletions(-)


-- 
~Randy