Re: [PATCH v14 11/11] kdump: update Documentation about crashkernel

From: chenzhou
Date: Wed Feb 03 2021 - 20:55:08 EST


Hi Randy,


On 2021/1/31 1:53, Randy Dunlap wrote:
> Hi--
>
> On 1/29/21 11:10 PM, Chen Zhou wrote:
>> ---
>> Documentation/admin-guide/kdump/kdump.rst | 22 ++++++++++++++++---
>> .../admin-guide/kernel-parameters.txt | 11 ++++++++--
>> 2 files changed, 28 insertions(+), 5 deletions(-)
>>
>> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
>> index a10b545c2070..908e5c8b61ba 100644
>> --- a/Documentation/admin-guide/kernel-parameters.txt
>> +++ b/Documentation/admin-guide/kernel-parameters.txt
> All of the "arm64" instances in [square brackets] should be "ARM64".
Got it, thanks for your review.

Thanks,
Chen Zhou
>
>> @@ -738,6 +738,9 @@
>> [KNL, X86-64] Select a region under 4G first, and
>> fall back to reserve region above 4G when '@offset'
>> hasn't been specified.
>> + [KNL, arm64] Try low allocation in DMA zone and fall back
> here
>
>> + to high allocation if it fails when '@offset' hasn't been
>> + specified.
>> See Documentation/admin-guide/kdump/kdump.rst for further details.
>>
>> crashkernel=range1:size1[,range2:size2,...][@offset]
>> @@ -754,6 +757,8 @@
>> Otherwise memory region will be allocated below 4G, if
>> available.
>> It will be ignored if crashkernel=X is specified.
>> + [KNL, arm64] range in high memory.
> here
>
>> + Allow kernel to allocate physical memory region from top.
>> crashkernel=size[KMG],low
>> [KNL, X86-64] range under 4G. When crashkernel=X,high
>> is passed, kernel could allocate physical memory region
>> @@ -762,13 +767,15 @@
>> requires at least 64M+32K low memory, also enough extra
>> low memory is needed to make sure DMA buffers for 32-bit
>> devices won't run out. Kernel would try to allocate at
>> - at least 256M below 4G automatically.
>> + least 256M below 4G automatically.
>> This one let user to specify own low range under 4G
>> for second kernel instead.
>> 0: to disable low allocation.
>> It will be ignored when crashkernel=X,high is not used
>> or memory reserved is below 4G.
>> -
>> + [KNL, arm64] range in low memory.
> here
>
>> + This one let user to specify a low range in DMA zone for
>> + crash dump kernel.
>
> Thanks.
>