[PATCH v7 00/17] riscv support for control flow integrity extensions

[Deepak Gupta <debug@rivosinc.com>]

v7 for riscv zicfilp and zicfiss extensions support in qemu.

Links for previous versions
[1] - v1 https://lists.nongnu.org/archive/html/qemu-devel/2024-07/msg06017.html
[2] - v2 https://lore.kernel.org/all/ed23bcbc-fdc4-4492-803c-daa95880375a@linaro.org/T/
[3] - v3 https://lists.nongnu.org/archive/html/qemu-devel/2024-08/msg01005.html
[4] - v4 https://lore.kernel.org/all/20240816010711.3055425-6-debug@rivosinc.com/T/
[5] - v5 https://lore.kernel.org/all/20240820000129.3522346-1-debug@rivosinc.com/T/#m7b9cc847e739ec86f9569a3ca9f3d9377b01e21
[6] - v6 https://mail.gnu.org/archive/html/qemu-riscv/2024-08/msg00418.html

---
v7:
   - Updated decode_save_opc to take extra argument of excp_uw2 and
     updated callsites
   - added a helper for promoting load faults to store faults
   - Removed stale comments and edited existed comments
v6:
   - Added support extra store word 2 for tcg compile and extraction during unwind
   - Using extra word, AMO instructions and shadow stack instructions can raise store fault
   - some alignment and cosmetic changes
   - added vmstate migration support for elp and ssp cpu state
v5:
   - Simplified elp tracking and lpad implementation as per suggestion by richard
   - Simplified shadow stack mmu checks as per suggestion by richard
   - Converged zicfiss compressed and non-comressed instructions to same translation
   - Removed trace hooks. Don't need for upstream.

v4:
   - elp state in cpu is true/false instead of enum and elp cleared
     unconditionally on trap entry. elp in *status cleared unconditionally on
     trap return.
   - Moved logic for branch tracking in instruction translation from tb_start.
   - fixed zicfiss dependency on 'A'
   - `cpu_get_fcfien/bcfien` helpers checks fixed to check for extension first.
   - removed trace hook enums. Instead added dedicated trace helpers wherever needed.
   - fixed/simplified instruction format in decoder for lpad, sspush, sspopchk
   - simplified tlb index logic for shadow stack instructions. Removed SUM TB_FLAG
   - access to ssp CSR is gated on `cpu_get_bcfien` instead of duplicated logic
   - removed vDSO related changes for now.
v3:
   - Removed prctl specific patches because they need to be upstream
     in kernel first.
   - As suggested by Richard, added TB flag if fcfi enabled
   - Re-worked translation for landing pad and shadow stack instructions
     to not require helper.
   - tcg helpers only for cfi violation cases so that trace hooks can be
     placed.
   - Style changes.
   - fixes assert condition in accel/tcg

v2:
   - added missed file (in v1) for shadow stack instructions implementation.

Deepak Gupta (17):
  target/riscv: Add zicfilp extension
  target/riscv: Introduce elp state and enabling controls for zicfilp
  target/riscv: save and restore elp state on priv transitions
  target/riscv: additional code information for sw check
  target/riscv: tracking indirect branches (fcfi) for zicfilp
  target/riscv: zicfilp `lpad` impl and branch tracking
  disas/riscv: enable `lpad` disassembly
  target/riscv: Add zicfiss extension
  target/riscv: introduce ssp and enabling controls for zicfiss
  target/riscv: tb flag for shadow stack  instructions
  target/riscv: mmu changes for zicfiss shadow stack protection
  target/riscv: AMO operations always raise store/AMO fault
  target/riscv: update `decode_save_opc` to store extra word2
  target/riscv: implement zicfiss instructions
  target/riscv: compressed encodings for sspush and sspopchk
  disas/riscv: enable disassembly for zicfiss instructions
  disas/riscv: enable disassembly for compressed sspush/sspopchk

 disas/riscv.c                                 |  77 ++++++++-
 disas/riscv.h                                 |   4 +
 target/riscv/cpu.c                            |  17 ++
 target/riscv/cpu.h                            |  24 ++-
 target/riscv/cpu_bits.h                       |  17 ++
 target/riscv/cpu_cfg.h                        |   2 +
 target/riscv/cpu_helper.c                     | 153 +++++++++++++++++-
 target/riscv/cpu_user.h                       |   1 +
 target/riscv/csr.c                            |  84 ++++++++++
 target/riscv/insn16.decode                    |   4 +
 target/riscv/insn32.decode                    |  26 ++-
 .../riscv/insn_trans/trans_privileged.c.inc   |   8 +-
 target/riscv/insn_trans/trans_rva.c.inc       |  43 ++++-
 target/riscv/insn_trans/trans_rvd.c.inc       |   4 +-
 target/riscv/insn_trans/trans_rvf.c.inc       |   4 +-
 target/riscv/insn_trans/trans_rvh.c.inc       |   8 +-
 target/riscv/insn_trans/trans_rvi.c.inc       |  61 ++++++-
 target/riscv/insn_trans/trans_rvvk.c.inc      |  10 +-
 target/riscv/insn_trans/trans_rvzacas.c.inc   |   4 +-
 target/riscv/insn_trans/trans_rvzfh.c.inc     |   4 +-
 target/riscv/insn_trans/trans_rvzicfiss.c.inc |  75 +++++++++
 target/riscv/insn_trans/trans_svinval.c.inc   |   6 +-
 target/riscv/internals.h                      |   3 +
 target/riscv/machine.c                        |  38 +++++
 target/riscv/op_helper.c                      |  18 +++
 target/riscv/pmp.c                            |   5 +
 target/riscv/pmp.h                            |   3 +-
 target/riscv/tcg/tcg-cpu.c                    |  25 +++
 target/riscv/translate.c                      |  45 +++++-
 29 files changed, 724 insertions(+), 49 deletions(-)
 create mode 100644 target/riscv/insn_trans/trans_rvzicfiss.c.inc

-- 
2.44.0