[PATCH v4 0/6] RISC-V kasan rework

[Alexandre Ghiti <alexghiti@rivosinc.com>]

As described in patch 2, our current kasan implementation is intricate,
so I tried to simplify the implementation and mimic what arm64/x86 are
doing.

In addition it fixes UEFI bootflow with a kasan kernel and kasan inline
instrumentation: all kasan configurations were tested on a large ubuntu
kernel with success with KASAN_KUNIT_TEST and KASAN_MODULE_TEST.

inline ubuntu config + uefi:
 sv39: OK
 sv48: OK
 sv57: OK

outline ubuntu config + uefi:
 sv39: OK
 sv48: OK
 sv57: OK

Actually 1 test always fails with KASAN_KUNIT_TEST that I have to check:
# kasan_bitops_generic: EXPECTATION FAILED at mm/kasan/kasan__test.c:1020
KASAN failure expected in "set_bit(nr, addr)", but none occurrred

Note that Palmer recently proposed to remove COMMAND_LINE_SIZE from the
userspace abi
https://lore.kernel.org/lkml/20221211061358.28035-1-palmer@rivosinc.com/T/
so that we can finally increase the command line to fit all kasan kernel
parameters.

All of this should hopefully fix the syzkaller riscv build that has been
failing for a few months now, any test is appreciated and if I can help
in any way, please ask.

base-commit-tag: v6.2-rc6

v4:
- Fix build warning by declaring create_tmp_mapping as static, kernel
  test robot

v3:
- Add AB from Ard in patch 4, thanks
- Fix checkpatch issues in patch 1, thanks Conor

v2:
- Rebase on top of v6.2-rc3
- patch 4 is now way simpler than it used to be since Ard already moved
  the string functions into the efistub.

Alexandre Ghiti (6):
  riscv: Split early and final KASAN population functions
  riscv: Rework kasan population functions
  riscv: Move DTB_EARLY_BASE_VA to the kernel address space
  riscv: Fix EFI stub usage of KASAN instrumented strcmp function
  riscv: Fix ptdump when KASAN is enabled
  riscv: Unconditionnally select KASAN_VMALLOC if KASAN

 arch/riscv/Kconfig             |   1 +
 arch/riscv/kernel/image-vars.h |   2 -
 arch/riscv/mm/init.c           |   2 +-
 arch/riscv/mm/kasan_init.c     | 516 ++++++++++++++++++---------------
 arch/riscv/mm/ptdump.c         |  24 +-
 5 files changed, 298 insertions(+), 247 deletions(-)

-- 
2.37.2