On 08/18/15 at 11:36pm, Toshi Kani wrote: > On 8/18/2015 8:53 PM, Baoquan He wrote: > >On 08/18/15 at 09:01am, Toshi Kani wrote: > >>On Tue, 2015-08-18 at 16:53 +0800, Baoquan He wrote: > >>>Rethink it again, maybe it's better to pass PMEM as PRAM to kdump > >>>kernel if user really want to use memmap way by specifying > >>>--pass-memmap-cmdline. Then I need add the PMEM and PRAM checking here > >>>you pointed out. Will repost with them. > >>No, you should not report PMEM as PRAM. They are different things. The > >>kdump kernel does not need to support memmap cmdline for PMEM, as the > >>regular kernel does not -- memmap cmdline cannot emulate PMEM. > >OK. Then it will be wrong if people intend to specify > >--pass-memmap-cmdline. There might be 3 ways to fix this: > > > >1) add PMEM support in kernel. memmap cmdline is not only used for > >emulating, but for kexec/kdump using. > > > >2) Delete --pass-memmap-cmdline option in kexec-tools since people > >rarely use it. > > > >3) Add a note in kexec-tools that option --pass-memmap-cmdline can't > >work together with PMEM, people should not use it. > > 3) is fine, and I do not think we need a note either. It does not > make sense to add an memmap cmdline for PMEM since PMEM ranges > require ACPI NFIT table. OK, got it. Let me repost without PMEM memmap adding. In fact I am a little confused that E820_PMEM is got by EFI in linux, seems in do_add_efi_memmap() though later ACPI NFIT need be read and more information about nvdimm will be got for nvdimm device. e820 memory map need be got from uefi/bios/kexec, this doesn't conflict with ACPI NFIT processing. Thanks Baoquan
