Support KASLR for RISC-V

This patch series implement KASLR for RISC-V. It copies kernel image to
a proper and random place, and make all harts go to the new destination.

This patch depends on the patch 'riscv: Introduce CONFIG_RELOCATABLE',
but given a small change by making PAGE_OFFSET be constant, so all the
memory could be available after moving kernel physical address. This
patch also depends on 'Support strict kernel memory permissions for security'.

Zong Li (8):
  riscv/kaslr: add interface to get kaslr offset
  riscv/kaslr: introduce functions to clear page table
  riscv/kaslr: support KASLR infrastructure
  riscv/kaslr: randomize the kernel image offset
  riscv/kaslr: support sparse memory model
  riscv/kaslr: clear the original kernel image
  riscv/kaslr: add cmdline support to disable KASLR
  riscv/kaslr: dump out kernel offset information on panic

 arch/riscv/Kconfig             |  15 ++
 arch/riscv/include/asm/kaslr.h |  12 +
 arch/riscv/include/asm/page.h  |   5 +
 arch/riscv/kernel/Makefile     |   2 +
 arch/riscv/kernel/head.S       |  39 +++
 arch/riscv/kernel/kaslr.c      | 442 +++++++++++++++++++++++++++++++++
 arch/riscv/kernel/setup.c      |  23 ++
 arch/riscv/mm/init.c           | 115 ++++++++-
 8 files changed, 651 insertions(+), 2 deletions(-)
 create mode 100644 arch/riscv/include/asm/kaslr.h
 create mode 100644 arch/riscv/kernel/kaslr.c

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2.25.1