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: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20220506114402.365-7-thunder.leizhen@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Zhen Lei 2022-05-06 19:44:02 +08:00 committed by Catalin Marinas
parent 8af6b91f58
commit 5832f1ae50
1 changed files with 7 additions and 2 deletions

View File

@ -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