diff options
| author | Will Deacon <will@kernel.org> | 2022-12-06 11:16:20 +0000 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-12-06 11:16:20 +0000 |
| commit | 926939c734fdac89cae27c9c93a28c30cde59fff (patch) | |
| tree | 2f959ec2f17d69e548e79b2a8983460ad20bf0a7 /Documentation | |
| parent | d864e90585f21e4e66bcf570bd743ca61dc6b7d1 (diff) | |
| parent | a9ae89df737756d92f0e14873339cf393f7f7eb0 (diff) | |
Merge branch 'for-next/kdump' into for-next/core
* for-next/kdump:
arm64: kdump: Support crashkernel=X fall back to reserve region above DMA zones
arm64: kdump: Provide default size when crashkernel=Y,low is not specified
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a465d5242774..9d458dfbec5f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -831,7 +831,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, X86-64] Select a region under 4G first, and + [KNL, X86-64, ARM64] Select a region under 4G first, and fall back to reserve region above 4G when '@offset' hasn't been specified. See Documentation/admin-guide/kdump/kdump.rst for further details. @@ -851,26 +851,23 @@ available. It will be ignored if crashkernel=X is specified. crashkernel=size[KMG],low - [KNL, X86-64] range under 4G. When crashkernel=X,high + [KNL, X86-64, ARM64] range under 4G. When crashkernel=X,high is passed, kernel could allocate physical memory region above 4G, that cause second kernel crash on system 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 least 256M below 4G automatically. + default size of memory below 4G automatically. The default + size is platform dependent. + --> x86: max(swiotlb_size_or_default() + 8MiB, 256MiB) + --> arm64: 128MiB This one lets the user 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. - 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 - or memory reserved is located in the DMA zones. - cryptomgr.notests [KNL] Disable crypto self-tests |