I have been able to get kexec working on ia64. I am attaching the kernel patch and kexec-tools patch. For the kernel patch, start with 2.6.8 kernel from kernel.org, apply ia64 patch , apply Eric' 2.6.8.1-kexec3 patch and apply attached 2.6.8.1-kexec3-ia64.diff patch. For kexec-tools, apply attached kexec-tools-1.98-ia64.diff patch to Eric's kexec-tools 1.98 sources . At this point, I have done minimal testing. Here is what I know does not work currently: 1. No support for initrd for kexec'd kernel 2. No support for new kernel parameters for kexec'd kernel. 3. If a kernel is booted up with "mem=" or "max_addr=" to restrict the amount of memory, a kernel kexec'd from this kernel will only see the same amount of memory as this one. This is not only due to the new kernel being kexec'd with the same parameter, but also becuase the EFI memory map as passed to the kernel by ELILO gets trimmed very early on by the kernel. I have tried adding code to save the memory map early on and then pass this saved memory map to kexec'd kernel, but apparently I still am not saving it early enough. I wait until bootmem allocator has been initailized so I can allocate memory to save unmolested EFI memory map in. In the process of initializing bootmem allocator, kernel calls efi-Memory_map_walk() which in turn trims the memory map. I am looking into allocating memory out of the EFI memory map before the first efi_mem_map_walk() happens, so I can save pristine EFI memmap for use later by kexec. Here is what I have not tested yet: 1. I am not sure if ACPI subsystem is happy in kexec'd kernel. I have not seen any problems, but I have not tested it enough either. 2. Stability of kexec'd kernel over long term. It ran fine for an hour not doing much :) Here is what I am working on next: 1. Save EFI memory map before it is trimmed. 2. Fix up /proc/iomem on ia64 so we can enable validating memory range in kexec tools. 3. Add a /proc interface to enable reboots on panic and INIT (and possibly MCA) to be kexec reboots. 4. Add initrd support. Any feedback on these patches is welcome. Any patch to fix problems in these patches is very much appreciated :) -- Khalid ==================================================================== Khalid Aziz Linux and Open Source Lab (970)898-9214 Hewlett-Packard khalid_aziz@hp.com Fort Collins, CO "The Linux kernel is subject to relentless development" - Alessandro Rubini