[ Added Mohan Kumar to CC list ] On Wed, Oct 22, 2008 at 03:39:18PM -0500, Milton Miller wrote: > The relocatable kernel kdump patch (54622f10a6aabb8bb2bdacf3dd070046f03dc246) > added a magic flag value in a register to tell purgatory that it should > be a panic kernel. This part is wrong and is reverted by this patch. > > The kernel gets a list of memory blocks and a entry point from user space. > Its job is to copy the blocks into place and then branch to the designated > entry point (after turning "off" the mmu). > > The user space tool inserts a trampoline, called purgatory, that runs > before the user supplied code. Its job is to establish the entry > environment for the new kernel or other application based on the contents > of memory. The purgatory code is compiled and embedded in the tool, > where it is later patched using the elf symbol table using elf symbols. > > Since the tool knows it is creating a purgatory that will run after a > kernel crash, it should just patch purgatory (or the kernel directly) > if something needs to happen. Hi Milton, All of these patches look fine to me. On the kernel side: Acked-by: Simon Horman <horms at verge.net.au> On the kexec-tools side: I'd rather wait until the kernel changes get merged before merging the kexec-tools portion. Please ping me at that point. I'd like to note that these changes really ought to go into the same kernel (and kexec-tools) release that the relocateable kdump patches as they will introduce incompatibility. For example, crash-dump kernels with only the relocatable kdump changes will not be usable if the first-kernel includes these changes. I think that means that this needs to go into 2.6.28 - assuming that Linus accepts the pull request than Ben Herrenschmidt sent recently. -- Simon Horman VA Linux Systems Japan K.K., Sydney, Australia Satellite Office H: www.vergenet.net/~horms/ W: www.valinux.co.jp/en
