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

Randy Dunlap rdunlap at infradead.org
Sat Jan 30 12:53:31 EST 2021


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".

> @@ -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.

-- 
~Randy




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