Previously Theodore Ts'o brought up an issue about kexec_load syscall bypassing signature verification: https://lkml.org/lkml/2015/6/14/280 Because we have two kexec load syscall, one kexec_load, another kexec_file_load, the latter one was introduced by Vivek Goyal, it is mainly for supporting UEFI secure boot. kexec_file_load verifies kernel signature, but even if with CONFIG_KEXEC_VERIFY_SIG=y and CONFIG_KEXEC_FILE=y, kexec-tools still can use old syscall and bypass signature verification. KEXEC_FILE can also be used without UEFI, so kexec can always verify kernel signature for security purpose. The suggestion in above thread is add a new Kconfig option for kexec common code, here I use KEXEC_CORE, KEXEC and KEXEC_FILE select KEXEC_CORE so one can compile only KEXEC_FILE without old kexec_load syscall. There's checkpatch warnings and errors, I would like to send furthuer cleanup patches after this series. Please let me know if you have other suggestions. checkpatch errors are for cases such as assign a value to static variables. PATCH 3/3 can be sort out from the series if people do not like. It is a cleanup for a macro. Below is the diffstat of the patches: --- arch/arm/Kconfig | 4 arch/ia64/Kconfig | 4 arch/m68k/Kconfig | 4 arch/mips/Kconfig | 4 arch/powerpc/Kconfig | 4 arch/sh/Kconfig | 4 arch/tile/Kconfig | 4 arch/x86/Kconfig | 6 arch/x86/boot/header.S | 2 arch/x86/include/asm/kdebug.h | 5 arch/x86/kernel/Makefile | 4 arch/x86/kernel/kvmclock.c | 4 arch/x86/kernel/reboot.c | 4 arch/x86/kernel/setup.c | 2 arch/x86/kernel/vmlinux.lds.S | 2 arch/x86/kvm/vmx.c | 8 arch/x86/platform/efi/efi.c | 4 arch/x86/platform/uv/uv_nmi.c | 6 drivers/firmware/efi/Kconfig | 2 drivers/pci/pci-driver.c | 2 include/linux/kexec.h | 12 init/initramfs.c | 4 kernel/Makefile | 2 kernel/events/core.c | 2 kernel/kexec.c | 2633 ------------------------------------------ kernel/kexec_core.c | 1594 +++++++++++++++++++++++++ kernel/kexec_file.c | 1044 ++++++++++++++++ kernel/kexec_internal.h | 22 kernel/ksysfs.c | 6 kernel/printk/printk.c | 2 kernel/reboot.c | 2 kernel/sysctl.c | 2 32 files changed, 2745 insertions(+), 2659 deletions(-) Thanks Dave
