This patch series enable reserving crashkernel on high memory in arm64. We use crashkernel=X to reserve crashkernel below 4G, which will fail when there is no enough memory. Currently, crashkernel=Y@X can be used to reserve crashkernel above 4G, in this case, if swiotlb or DMA buffers are requierd, capture kernel will boot failure because of no low memory. When crashkernel is reserved above 4G in memory, kernel should reserve some amount of low memory for swiotlb and some DMA buffers. So there may be two crash kernel regions, one is below 4G, the other is above 4G. Then Crash dump kernel reads more than one crash kernel regions via a dtb property under node /chosen, linux,usable-memory-range = <BASE1 SIZE1 [BASE2 SIZE2]>. Besides, we need to modify kexec-tools: arm64: support more than one crash kernel regions(see [1]) I post this patch series about one month ago. The previous changes and discussions can be retrived from: Changes since [v4] - reimplement memblock_cap_memory_ranges for multiple ranges by Mike. Changes since [v3] - Add memblock_cap_memory_ranges back for multiple ranges. - Fix some compiling warnings. Changes since [v2] - Split patch "arm64: kdump: support reserving crashkernel above 4G" as two. Put "move reserve_crashkernel_low() into kexec_core.c" in a separate patch. Changes since [v1]: - Move common reserve_crashkernel_low() code into kernel/kexec_core.c. - Remove memblock_cap_memory_ranges() i added in v1 and implement that in fdt_enforce_memory_region(). There are at most two crash kernel regions, for two crash kernel regions case, we cap the memory range [min(regs[*].start), max(regs[*].end)] and then remove the memory range in the middle. [1]: http://lists.infradead.org/pipermail/kexec/2019-April/022792.html [v1]: https://lkml.org/lkml/2019/4/2/1174 [v2]: https://lkml.org/lkml/2019/4/9/86 [v3]: https://lkml.org/lkml/2019/4/9/306 [v4]: https://lkml.org/lkml/2019/4/15/273 Chen Zhou (3): x86: kdump: move reserve_crashkernel_low() into kexec_core.c arm64: kdump: support reserving crashkernel above 4G kdump: update Documentation about crashkernel on arm64 Mike Rapoport (1): memblock: extend memblock_cap_memory_range to multiple ranges Documentation/admin-guide/kernel-parameters.txt | 6 +-- arch/arm64/include/asm/kexec.h | 3 ++ arch/arm64/kernel/setup.c | 3 ++ arch/arm64/mm/init.c | 72 +++++++++++++++++++------ arch/x86/include/asm/kexec.h | 3 ++ arch/x86/kernel/setup.c | 66 +++-------------------- include/linux/kexec.h | 5 ++ include/linux/memblock.h | 2 +- kernel/kexec_core.c | 56 +++++++++++++++++++ mm/memblock.c | 44 +++++++-------- 10 files changed, 157 insertions(+), 103 deletions(-) -- 2.7.4
