From: Quan Zhou zhouquan@iscas.ac.cn
Expose orig_a0 to userspace to ensure that users can modify the actual value of `a0` in the traced process through the ptrace(PTRACE_SETREGSET, ...) path. Since user_regs_struct is a subset of pt_regs, we also need to adjust the position of the orig_a0 field in pt_regs to achieve the correct copy.
Signed-off-by: Quan Zhou zhouquan@iscas.ac.cn --- arch/riscv/include/asm/ptrace.h | 4 ++-- arch/riscv/include/uapi/asm/ptrace.h | 2 ++ 2 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h index b5b0adcc85c1..37f48d40ae46 100644 --- a/arch/riscv/include/asm/ptrace.h +++ b/arch/riscv/include/asm/ptrace.h @@ -45,12 +45,12 @@ struct pt_regs { unsigned long t4; unsigned long t5; unsigned long t6; + /* a0 value before the syscall */ + unsigned long orig_a0; /* Supervisor/Machine CSRs */ unsigned long status; unsigned long badaddr; unsigned long cause; - /* a0 value before the syscall */ - unsigned long orig_a0; };
#define PTRACE_SYSEMU 0x1f diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h index a38268b19c3d..3e37f80cb3e8 100644 --- a/arch/riscv/include/uapi/asm/ptrace.h +++ b/arch/riscv/include/uapi/asm/ptrace.h @@ -54,6 +54,8 @@ struct user_regs_struct { unsigned long t4; unsigned long t5; unsigned long t6; + /* a0 value before the syscall */ + unsigned long orig_a0; };
struct __riscv_f_ext_state {