From mboxrd@z Thu Jan 1 00:00:00 1970 From: Khalid Aziz Date: Tue, 16 Nov 2004 03:46:49 +0000 Subject: Re: [Fastboot] [PATCH] kexec on ia64 Message-Id: <1100576808.2371.0.camel@minuet.fc.hp.com> List-Id: References: <1100551268.26287.35.camel@lyra.fc.hp.com> In-Reply-To: <1100551268.26287.35.camel@lyra.fc.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Another limitation I forgot to mention. I have not added support for compressed kernel to kexec-tools yet. It is on my list of things to do next. -- Khalid On Mon, 2004-11-15 at 13:32, Khalid Aziz wrote: > 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 Aziz Linux and Open Source Lab (970)898-9214 Hewlett-Packard khalid_aziz@hp.com Fort Collins, CO