On Tue, Feb 15, 2022 at 8:46 AM Helge Deller <deller@xxxxxx> wrote:
>
> On 2/15/22 04:03, Al Viro wrote:
> > On Mon, Feb 14, 2022 at 05:34:52PM +0100, Arnd Bergmann wrote:
> >> diff --git a/arch/parisc/include/asm/futex.h b/arch/parisc/include/asm/futex.h
> >> index b5835325d44b..2f4a1b1ef387 100644
> >> --- a/arch/parisc/include/asm/futex.h
> >> +++ b/arch/parisc/include/asm/futex.h
> >> @@ -99,7 +99,7 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
> >> /* futex.c wants to do a cmpxchg_inatomic on kernel NULL, which is
> >> * our gateway page, and causes no end of trouble...
> >> */
> >> - if (uaccess_kernel() && !uaddr)
> >> + if (!uaddr)
> >> return -EFAULT;
> >
> > Huh? uaccess_kernel() is removed since it becomes always false now,
> > so this looks odd.
> >
> > AFAICS, the comment above that check refers to futex_detect_cmpxchg()
> > -> cmpxchg_futex_value_locked() -> futex_atomic_cmpxchg_inatomic() call chain.
> > Which had been gone since commit 3297481d688a (futex: Remove futex_cmpxchg
> > detection). The comment *and* the check should've been killed off back
> > then.
> > Let's make sure to get both now...
>
> Right. Arnd, can you drop this if() and the comment above it?
Done.
Arnd
