http://lkml.org/lkml/2008/9/13/19(Sorry, I mangled the first patch series. Please disregard those messages.) These RFC patches add support for Ksplice [1], a rebootless update system, to the kernel. I previously mentioned Ksplice to the LKML a few months ago [2]. The basic idea is that Ksplice can apply an update to a running Linux kernel based only on a source code patch and the original kernel source. The Ksplice technical overview document [3] describes the design of Ksplice and one of the ways that Ksplice has been evaluated. [1] http://web.mit.edu/ksplice [2] http://lkml.org/lkml/2008/4/23/330 [3] http://web.mit.edu/ksplice/doc/ksplice.pdf The interface between the Ksplice kernel component and the userspace utilities is documented in patch 6/9 of this series. The current implementation of the userspace utilities is available from the Ksplice website and the Ksplice git repository [4]. The Ksplice userspace utilities transparently support both "integrated" operation (updating a kernel patched with this patch series) and "standalone" operation (updating a completely unmodified kernel). [4] http://web.mit.edu/ksplice/ksplice.git This series of patches depends upon the -ffunction-sections and -fdata-sections patches proposed by Denys Vlasenko (for reasons unrelated to Ksplice) a few weeks ago [5]. Ksplice's 'run-pre matching' process is much simpler if the original kernel was compiled with -ffunction-sections and -fdata-sections, and so we require these compiler options for this patch series. We think that requiring these options in order to build a kernel with integrated Ksplice support is reasonable, but we welcome feedback. [5] http://lkml.org/lkml/2008/8/24/159 Denys Vlasenko has already submitted patches to the LKML for allowing all architectures to compile with -ffunction-sections and -fdata-sections [5]; he has said that he will later submit patches making it possible to run a kernel with these options [6]. In the meantime, we have a patch that creates a CONFIG_FUNCTION_DATA_SECTIONS option for x86 and ARM [7], but we have not polished this patch since Denys Vlasenko is already preparing a similar change. [6] http://lkml.org/lkml/2008/8/26/288 [7] http://web.mit.edu/ksplice/tmp/function-data-sections.patch We're open to suggestions and are available to make whatever changes people would like to see. (Also, I'll be at the Plumbers Conference next week and would be happy to chat with anyone about Ksplice in person). Jeff Arnold jbarn...@mit.edu -- Documentation/ksplice.txt | 247 +++++ MAINTAINERS | 10 + arch/Kconfig | 14 + arch/arm/Kconfig | 1 + arch/arm/kernel/ksplice-arch.c | 79 ++ arch/x86/Kconfig | 1 + arch/x86/kernel/ksplice-arch.c | 91 ++ arch/x86/mm/init_32.c | 7 +- arch/x86/mm/init_64.c | 5 +- include/linux/kallsyms.h | 13 + include/linux/ksplice.h | 202 ++++ include/linux/module.h | 27 + kernel/Makefile | 2 + kernel/kallsyms.c | 19 + kernel/ksplice.c | 1997 ++++++++++++++++++++++++++++++++++++++++ kernel/module.c | 144 ++- kernel/sched.c | 1 + 17 files changed, 2810 insertions(+), 50 deletions(-) |
