[PATCH bpf-next v11 0/3] Support kCFI + BPF on arm64

[Sami Tolvanen]

Hi folks,

These patches add KCFI types to arm64 BPF JIT output. Puranjay and
Maxwell have been working on this for some time now, but I haven't
seen any progress since June 2024, so I decided to pick up the latest
version[1] posted by Maxwell and fix the few remaining issues I
noticed. I confirmed that with these patches applied, I no longer see
CFI failures in jitted code when running BPF self-tests on arm64.

[1] https://lore.kernel.org/linux-arm-kernel/ptrugmna4xb5o5lo4xislf4rlz7avdmd4pfho5fjwtjj7v422u@iqrwfrbwuxrq/

Sami

---
v11:
- Moved cfi_get_func_hash to a static inline with an ifdef guard.
- Picked by Will's Acked-by tags.

v10: https://lore.kernel.org/bpf/20250715225733.3921432-5-samitolvanen@google.com/
- Rebased to bpf-next/master again.
- Added a patch to moved duplicate type hash variables and helper
  functions to common CFI code.

v9: https://lore.kernel.org/bpf/20250505223437.3722164-4-samitolvanen@google.com/
- Rebased to bpf-next/master to fix merge x86 merge conflicts.
- Fixed checkpatch warnings about Co-developed-by tags and including
  <asm/cfi.h>.
- Picked up Tested-by tags.

v8: https://lore.kernel.org/bpf/20250310222942.1988975-4-samitolvanen@google.com/
- Changed DEFINE_CFI_TYPE to use .4byte to match __CFI_TYPE.
- Changed cfi_get_func_hash() to again use get_kernel_nofault().
- Fixed a panic in bpf_jit_free() by resetting prog->bpf_func before
  calling bpf_jit_binary_pack_hdr().

---
Mark Rutland (1):
  cfi: add C CFI type macro

Puranjay Mohan (1):
  arm64/cfi,bpf: Support kCFI + BPF on arm64

Sami Tolvanen (1):
  cfi: Move BPF CFI types and helpers to generic code

 arch/arm64/include/asm/cfi.h  |  7 +++++
 arch/arm64/net/bpf_jit_comp.c | 22 +++++++++++++--
 arch/riscv/include/asm/cfi.h  | 16 -----------
 arch/riscv/kernel/cfi.c       | 53 -----------------------------------
 arch/x86/include/asm/cfi.h    | 10 ++-----
 arch/x86/kernel/alternative.c | 37 ------------------------
 include/linux/cfi.h           | 47 +++++++++++++++++++++++++------
 include/linux/cfi_types.h     | 23 +++++++++++++++
 kernel/cfi.c                  | 15 ++++++++++
 9 files changed, 105 insertions(+), 125 deletions(-)
 create mode 100644 arch/arm64/include/asm/cfi.h


base-commit: 0ee30d937c147fc14c4b49535181d437cd2fde7a
-- 
2.50.0.727.gbf7dc18ff4-goog