UPT_DX             16 arch/x86/um/asm/ptrace.h #define PT_REGS_DX(r) UPT_DX(&(r)->regs)
UPT_DX             17 arch/x86/um/shared/sysdep/ptrace_32.h #define UPT_SYSCALL_ARG3(r) UPT_DX(r)
UPT_DX             55 arch/x86/um/shared/sysdep/ptrace_64.h #define UPT_SYSCALL_ARG3(r) UPT_DX(r)