Re: [PATCH 1/7] arm64: Move __ARCH_WANT_SYS_CLONE3 definition to uapi headers

Arnd Bergmann
2020-01-02T19:59:32Z

On Thu, Jan 2, 2020 at 8:33 PM Amanieu d'Antras <amanieu@gmail.com> wrote:
>
> On Thu, Jan 2, 2020 at 8:25 PM Arnd Bergmann <arnd@arndb.de> wrote:
> > On Thu, Jan 2, 2020 at 6:50 PM Christian Brauner
> > <christian.brauner@ubuntu.com> wrote:
> > > On Thu, Jan 02, 2020 at 06:24:07PM +0100, Amanieu d'Antras wrote:
> > > > Previously this was only defined in the internal headers which
> > > > resulted in __NR_clone3 not being defined in the user headers.
> > > >
> > > > Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
> > > > Cc: linux-arm-kernel@lists.infradead.org
> > > > Cc: <stable@vger.kernel.org> # 5.3.x
> > > > ---
> > > > arch/arm64/include/asm/unistd.h | 1 -
> > > > arch/arm64/include/uapi/asm/unistd.h | 1 +
> > > > 2 files changed, 1 insertion(+), 1 deletion(-)
> >
> > Good catch, this is clearly needed, but please make the patch change
> > every copy of asm/unistd.h that defines this, not just the arm64 one.
>
> Actually __ARCH_WANT_SYS_CLONE3 only needs to be in the uapi headers
> for architectures that use the asm-generic/unistd.h header, which uses
> it to guard the definition of __NR_clone3. Architectures not using the
> asm-generic header don't need this define to export __NR_clone3. The
> only other architecture with clone3 that uses the asm-generic header
> is riscv, which already defines __ARCH_WANT_SYS_CLONE3 in the uapi
> headers.

Ah, of course. The patch looks fine to me then.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>