Hi Catalin, Sorry to ping you. What's your suggestion about this patch series? I am looking forward to your replay. Thanks, Chen Zhou On 2019/5/16 11:19, Chen Zhou wrote: > Hi Bhupesh, > > On 2019/5/15 13:06, Bhupesh Sharma wrote: >> +Cc kexec-list. >> >> Hi Chen, >> >> I think we are still in the quiet period of the merge cycle, but this is a change which will be useful for systems like HPE Apollo where we are looking at reserving crashkernel across a larger range. >> >> Some comments inline and in respective patch threads.. >> >> On 05/07/2019 09:20 AM, Chen Zhou wrote: >>> This patch series enable reserving crashkernel on high memory in arm64. >> >> Please fix the patch subject, it should be v5. >> Also please Cc the kexec-list (kexec@xxxxxxxxxxxxxxxxxxx) for future versions to allow wider review of the patchset. >> >>> 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. >> >> ... ^^ required >> >> s/capture kernel will boot failure because of no low memory./capture kernel boot will fail because there is no low memory available for allocation. >> >>> 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]>. >> >> Please use consistent naming for the second kernel, better to use crash dump kernel. >> >> I have tested this on my HPE Apollo machine and with crashkernel=886M,high syntax, I can get the board to reserve a larger memory range for the crashkernel (i.e. 886M): >> >> # dmesg | grep -i crash >> [ 0.000000] kexec_core: Reserving 256MB of low memory at 3560MB for crashkernel (System low RAM: 2029MB) >> [ 0.000000] crashkernel reserved: 0x0000000bc5a00000 - 0x0000000bfd000000 (886 MB) >> >> kexec/kdump can also work also work fine on the board. >> >> So, with the changes suggested in this cover letter and individual patches, please feel free to add: >> >> Reviewed-and-Tested-by: Bhupesh Sharma <bhsharma@xxxxxxxxxx> >> >> Thanks, >> Bhupesh >> > > Thanks for you review and test. I will fix these later. > > Thanks, > Chen Zhou > >>> 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(-) >>> >> >> >> . >> > > > . >
