Yu-cheng, Am 20.06.2017 um 20:04 schrieb Yu-cheng Yu: >>> So to summarize: >>> >>> - PTRACE_GETREGSET with NT_X86_XSTATE gets 832 and return 832, with no >>> error. >>> >>> - PTRACE_SETREGSET get 832 (sizeof struct _xstate) but wants at least >>> 1088, otherwise it will fail with -EFAULT (why not -EINVAL?) >>> >>> Ideas? > > We considered allowing a partial XSAVE buffer for PTRACE_SETREGSET, but > it was that the XSAVE instruction requires a full-size buffer led to > this choice. Using a smaller buffer for XSAVE causes a fault. So, this code is not supposed to work? iov.iov_base = fp_regs; iov.iov_len = sizeof(struct _xstate); ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov); ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov); This is what UML does and on Thomas's new Laptop PTRACE_SETREGSET is failing. Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-x86_64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
