From: Al Viro <viro@xxxxxxxxxxxxxxxxxx> Date: Tue, 19 Jan 2016 21:55:36 +0000 > On Tue, Jan 19, 2016 at 01:47:24PM -0800, Andy Lutomirski wrote: >> Essentially all users of is_compat_task in the kernel are trying to >> determine whether they are executing in the context of a compat >> syscall. On at least x86_64 and sparc, these are not at all the >> same question. >> >> On x86_64 and sparc, therefore, is_compat_task doesn't return the >> overall compat state of the task; it returns true if the task is >> currently in a compat syscall. > > The hell it does. Andy, TIF_32BIT is *NOT* set on syscall entry; it is > set by execve(). And 64bit task (with that bit clear) can bloody well > issue 32bit syscalls. Really. Correct. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html