Commit 5832f1ae authored by Zhen Lei's avatar Zhen Lei Committed by Catalin Marinas
Browse files

docs: kdump: Update the crashkernel description for arm64 



Now arm64 has added support for "crashkernel=X,high" and
"crashkernel=Y,low". Unlike x86, crash low memory is not allocated if
"crashkernel=Y,low" is not specified.

Signed-off-by: default avatarZhen Lei <thunder.leizhen@huawei.com>
Acked-by: default avatarBaoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20220506114402.365-7-thunder.leizhen@huawei.com


Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 8af6b91f

Documentation/admin-guide/kernel-parameters.txt

+7 −2
Original line number Diff line number Diff line
@@ -808,7 +808,7 @@ 
			Documentation/admin-guide/kdump/kdump.rst for an example.



	crashkernel=size[KMG],high

			[KNL, X86-64] range could be above 4G. Allow kernel

			[KNL, X86-64, ARM64] range could be above 4G. Allow kernel

			to allocate physical memory region from top, so could

			be above 4G if system have more than 4G ram installed.

			Otherwise memory region will be allocated below 4G, if
@@ -821,7 +821,7 @@ 
			that require some amount of low memory, e.g. swiotlb

			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

			devices won't run out. Kernel would try to allocate

			at least 256M below 4G automatically.

			This one let user to specify own low range under 4G

			for second kernel instead.
@@ -829,6 +829,11 @@ 
			It will be ignored when crashkernel=X,high is not used

			or memory reserved is below 4G.



			[KNL, ARM64] range in low memory.

			This one lets the user specify a low range in the

			DMA zone for the crash dump kernel.

			It will be ignored when crashkernel=X,high is not used.



	cryptomgr.notests

			[KNL] Disable crypto self-tests