From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Kerrisk (man-pages)" Subject: Re: [PATCH 3/3] clone.2: Use pid_t for clone3() {child,parent}_tid Date: Sun, 17 Nov 2019 19:02:04 +0100 Message-ID: References: <20191116114114.7066-1-christian@brauner.io> <20191116114114.7066-3-christian@brauner.io> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20191116114114.7066-3-christian@brauner.io> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Christian Brauner Cc: mtk.manpages@gmail.com, adrian@lisas.de, akpm@linux-foundation.org, arnd@arndb.de, avagin@gmail.com, christian.brauner@ubuntu.com, dhowells@redhat.com, fweimer@redhat.com, jannh@google.com, keescook@chromium.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-man@vger.kernel.org, mingo@elte.hu, oleg@redhat.com, xemul@virtuozzo.com List-Id: linux-api@vger.kernel.org On 11/16/19 12:41 PM, Christian Brauner wrote: > From: Christian Brauner > > Advertise to userspace that they should use proper pid_t types for > arguments returning a pid. > The kernel-internal struct kernel_clone_args currently uses int as type > and since POSIX mandates that pid_t is a signed integer type and glibc > and friends use int this is not an issue. After the merge window for > v5.5 closes we can switch struct kernel_clone_args over to using pid_t > as well without any danger in regressing current userspace. > Also note, that the new set tid feature which will be merged for v5.5 > uses pid_t types as well. Thanks taking a further pass throuh this page, Christian, Patch applied. Cheers, Michael > Signed-off-by: Christian Brauner > --- > man2/clone.2 | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/man2/clone.2 b/man2/clone.2 > index faff2ada6..bf2d7c731 100644 > --- a/man2/clone.2 > +++ b/man2/clone.2 > @@ -183,9 +183,9 @@ is a structure of the following form: > struct clone_args { > u64 flags; /* Flags bit mask */ > u64 pidfd; /* Where to store PID file descriptor > - (\fIint *\fP) */ > + (\fIpid_t *\fP) */ > u64 child_tid; /* Where to store child TID, > - in child's memory (\fIint *\fP) */ > + in child's memory (\fIpid_t *\fP) */ > u64 parent_tid; /* Where to store child TID, > in parent's memory (\fIint *\fP) */ > u64 exit_signal; /* Signal to deliver to parent on > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/