Re: [PATCH] Add +~800M crashkernel explaination

From: Xunlei Pang
Date: Wed Jan 11 2017 - 22:23:29 EST


On 01/12/2017 at 03:35 AM, Robert LeBlanc wrote:
> On Wed, Dec 14, 2016 at 4:17 PM, Xunlei Pang <xpang@xxxxxxxxxx> wrote:
>> As I replied in another post, if you really want to detail the behaviour, should mention
>> "crashkernel=size[KMG][@offset[KMG]]" with @offset[KMG] specified explicitly, after
>> all, it's handled differently with no upper bound limitation, but doing this may put
>> the first kernel at the risk of lacking low memory(some devices require 32bit DMA),
>> must use it with care because the kernel will assume users are aware of what they
>> are doing and make a successful reservation as long as the given range is available.
> crashkernel=1024M@0x10000000
>
> I can't get the offset to work. It seems that it allocates the space
> and loads the crash kernel, but I couldn't get it to actually boot
> into the crash kernel. Does it work for you? I'm using the 4.9 kernel.

Not sure what is the problem you met, but kdump kernel boots well using 4.9 on my x86_64 machine.

Regards,
Xunlei