On Fri, Dec 21, 2007 at 03:33:19PM +0800, Huang, Ying wrote: [..] > The following user-space tools can be used with kexec jump. > > 1. kexec-tools needs to be patched to support kexec jump. The patches > and the precompiled kexec can be download from the following URL: > source: http://khibernation.sourceforge.net/download/release_v8/kexec-tools/kexec-tools-src_git_kh8.tar.bz2 > patches: http://khibernation.sourceforge.net/download/release_v8/kexec-tools/kexec-tools-patches_git_kh8.tar.bz2 > binary: http://khibernation.sourceforge.net/download/release_v8/kexec-tools/kexec_git_kh8 > > 2. makedumpfile with patches are used as memory image saving tool, it > can exclude free pages from original kernel memory image file. The > patches and the precompiled makedumpfile can be download from the > following URL: > source: http://khibernation.sourceforge.net/download/release_v8/makedumpfile/makedumpfile-src_cvs_kh8.tar.bz2 > patches: http://khibernation.sourceforge.net/download/release_v8/makedumpfile/makedumpfile-patches_cvs_kh8.tar.bz2 > binary: http://khibernation.sourceforge.net/download/release_v8/makedumpfile/makedumpfile_cvs_kh8 > > 3. A simplest memory image restoring tool named "krestore" is > implemented. It can be downloaded from the following URL: > source: http://khibernation.sourceforge.net/download/release_v8/krestore/krestore-src_cvs_kh8.tar.bz2 > binary: http://khibernation.sourceforge.net/download/release_v8/krestore/krestore_cvs_kh8 > > An initramfs image can be used as the root file system of kexeced > kernel. An initramfs image built with "BuildRoot" can be downloaded > from the following URL: > initramfs image: http://khibernation.sourceforge.net/download/release_v8/initramfs/rootfs_cvs_kh8.gz > All user space tools above are included in the initramfs image. > > > Usage example of jumping between original and kexeced kernel: > > 1. Compile and install patched kernel with following options selected: > > CONFIG_X86_32=y > CONFIG_RELOCATABLE=y > CONFIG_KEXEC=y > CONFIG_CRASH_DUMP=y > CONFIG_PM=y > > 2. Build an initramfs image contains kexec-tool, or download the > pre-built initramfs image, called rootfs.gz in following text. > > 3. Boot kernel compiled in step 1. > > 4. Load kernel compiled in step 1 with /sbin/kexec. If You want to use > "krestore" tool, the --elf64-core-headers should be specified in > command line of /sbin/kexec. The shell command line can be as > follow: > > /sbin/kexec --load-jump-back /boot/bzImage --mem-min=0x100000 > --mem-max=0xffffff --elf64-core-headers --initrd=rootfs.gz > > 5. Boot the kexeced kernel with following shell command line: > > /sbin/kexec -e > > 6. The kexeced kernel will boot as normal kexec. In kexeced kernel the > memory image of original kernel can read via /proc/vmcore or > /dev/oldmem, and can be written via /dev/oldmem. You can > save/restore/modify it as you want to. > > 7. Prepare jumping back from kexeced kernel with following shell > command lines: > > jump_back_entry=`cat /proc/cmdline | tr ' ' '\n' | grep kexec_jump_back_entry | cut -d '='` > /sbin/kexec --load-jump-back-helper=$jump_back_entry > > 8. Jump back to the original kernel with following shell command line: > > /sbin/kexec -e > > 9. Now, you are in the original kernel again. You can read/write the > memory image of kexeced kernel via /proc/kimgcore. > Why do we need two interfaces, /proc/vmcore and /proc/kimgcore? Can't we have just one say /proc/vmcore. Irrespective of what kernel you are in /proc/vmcore gives you the access to the memory of kernel which was previously booted. Thanks Vivek _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
