Re: [PATCH] uprobes/x86: fix detection of 32-bit user mode

From: Thomas Gleixner
Date: Fri Aug 23 2019 - 20:00:45 EST


On Fri, 23 Aug 2019, Andy Lutomirski wrote:
> > On Aug 23, 2019, at 4:44 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> >
> >> On Sat, 24 Aug 2019, Thomas Gleixner wrote:
> >>> On Sun, 28 Jul 2019, Sebastian Mayr wrote:
> >>>
> >>> -static inline int sizeof_long(void)
> >>> +static inline int sizeof_long(struct pt_regs *regs)
> >>> {
> >>> - return in_ia32_syscall() ? 4 : 8;
> >>
> >> This wants a comment.
> >>
> >>> + return user_64bit_mode(regs) ? 8 : 4;
> >
> > The more simpler one liner is to check
> >
> > test_thread_flag(TIF_IA32)
>
> I still want to finish killing TIF_IA32 some day. Letâs please not add new users.

Well, yes and no. This needs to be backported ....