On 11/03/14 at 07:46pm, Mark Rutland wrote: > On Fri, Oct 31, 2014 at 07:52:09AM +0000, Dave Young wrote: > > Hi Geoff > > > > I tested your patches. The macihne is using spin-table cpu enable method > > so I tried maxcpus=1 as you suggested. > > > > There's below issues for me, thoughts? > > > > 1. For acpi booting there's no /proc/device-tree so kexec can not find dtb > > to use. > > Are you absolutely certain of this? > > To use ACPI, you must have booted via EFI, as the only mechanism for > finding the ACPI tables is via EFI. If booted via EFI, the stub will > have created a stub DTB if there is no provided DTB, to pass the command > line and pointers to EFI data structures. This stub DTB should be > present in the usual place. Mark, I used kexec-tools from Geoff's git tree, it will create dtb from procfs maybe I can pass external dtb to kexec-tools. What you mentioned should be true though but I have not get idea how to get the dtb which kernel is using for boot since it is not unflattened. Thanks Dave
