Re: [GIT PULL 1/4] ARM: SoC platform updates
On Thu, May 16, 2019 at 7:10 PM Olof Johansson wrote: > On Thu, May 16, 2019 at 8:53 AM Arnd Bergmann wrote: > > > I'm going to remove that #ifdef in my merge, because I do *not* want > > > to see new warnings, and it doesn't seem to make any sense. > > > > > > Maybe that's the wrong resolution, please holler and let me know if > > > you want something else. > > > > As far as I can tell, that is the best fix, thanks for the cleanup! > > Yeah, this was entirely on me -- it was found and fixed on linux-next, > and Linus Walleij sent patches. However, as I was staging these pull > requests, I applied them to a branch of fixes that I'm collecting for > later this week instead of on top of the one I was sending. > > Thanks for fixing it up. Oh well Linus wrote the bug and then Linus fixed it and then Linus fixed it. What is good to know is that no matter which Linus you use, you will always get the right fix. Yours, Linus Walleij
[PATCH v3 2/2] tests: add pidfd_open() tests
This adds testing for the new pidfd_open() syscalls. Specifically, we test:
- that no invalid flags can be passed to pidfd_open()
- that no invalid pid can be passed to pidfd_open()
- that a pidfd can be retrieved with pidfd_open()
- that the retrieved pidfd references the correct pid
Signed-off-by: Christian Brauner
Cc: Arnd Bergmann
Cc: "Eric W. Biederman"
Cc: Kees Cook
Cc: Joel Fernandes (Google)
Cc: Thomas Gleixner
Cc: Jann Horn
Cc: David Howells
Cc: "Michael Kerrisk (man-pages)"
Cc: Andy Lutomirsky
Cc: Andrew Morton
Cc: Oleg Nesterov
Cc: Aleksa Sarai
Cc: Linus Torvalds
Cc: Al Viro
Cc: linux-...@vger.kernel.org
---
v1: unchanged
v2:
- Christian Brauner :
- set number of planned tests via ksft_set_plan()
v3: unchanged
---
tools/testing/selftests/pidfd/.gitignore | 1 +
tools/testing/selftests/pidfd/Makefile| 2 +-
tools/testing/selftests/pidfd/pidfd.h | 57 ++
.../testing/selftests/pidfd/pidfd_open_test.c | 169 ++
tools/testing/selftests/pidfd/pidfd_test.c| 41 +
5 files changed, 229 insertions(+), 41 deletions(-)
create mode 100644 tools/testing/selftests/pidfd/pidfd.h
create mode 100644 tools/testing/selftests/pidfd/pidfd_open_test.c
diff --git a/tools/testing/selftests/pidfd/.gitignore
b/tools/testing/selftests/pidfd/.gitignore
index 822a1e63d045..16d84d117bc0 100644
--- a/tools/testing/selftests/pidfd/.gitignore
+++ b/tools/testing/selftests/pidfd/.gitignore
@@ -1 +1,2 @@
+pidfd_open_test
pidfd_test
diff --git a/tools/testing/selftests/pidfd/Makefile
b/tools/testing/selftests/pidfd/Makefile
index deaf8073bc06..b36c0be70848 100644
--- a/tools/testing/selftests/pidfd/Makefile
+++ b/tools/testing/selftests/pidfd/Makefile
@@ -1,6 +1,6 @@
CFLAGS += -g -I../../../../usr/include/
-TEST_GEN_PROGS := pidfd_test
+TEST_GEN_PROGS := pidfd_test pidfd_open_test
include ../lib.mk
diff --git a/tools/testing/selftests/pidfd/pidfd.h
b/tools/testing/selftests/pidfd/pidfd.h
new file mode 100644
index ..8452e910463f
--- /dev/null
+++ b/tools/testing/selftests/pidfd/pidfd.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __PIDFD_H
+#define __PIDFD_H
+
+#define _GNU_SOURCE
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include "../kselftest.h"
+
+/*
+ * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
+ * That means, when it wraps around any pid < 300 will be skipped.
+ * So we need to use a pid > 300 in order to test recycling.
+ */
+#define PID_RECYCLE 1000
+
+/*
+ * Define a few custom error codes for the child process to clearly indicate
+ * what is happening. This way we can tell the difference between a system
+ * error, a test error, etc.
+ */
+#define PIDFD_PASS 0
+#define PIDFD_FAIL 1
+#define PIDFD_ERROR 2
+#define PIDFD_SKIP 3
+#define PIDFD_XFAIL 4
+
+int wait_for_pid(pid_t pid)
+{
+ int status, ret;
+
+again:
+ ret = waitpid(pid, , 0);
+ if (ret == -1) {
+ if (errno == EINTR)
+ goto again;
+
+ return -1;
+ }
+
+ if (!WIFEXITED(status))
+ return -1;
+
+ return WEXITSTATUS(status);
+}
+
+
+#endif /* __PIDFD_H */
diff --git a/tools/testing/selftests/pidfd/pidfd_open_test.c
b/tools/testing/selftests/pidfd/pidfd_open_test.c
new file mode 100644
index ..0377133dd6dc
--- /dev/null
+++ b/tools/testing/selftests/pidfd/pidfd_open_test.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include "pidfd.h"
+#include "../kselftest.h"
+
+static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
+{
+ return syscall(__NR_pidfd_open, pid, flags);
+}
+
+static int safe_int(const char *numstr, int *converted)
+{
+ char *err = NULL;
+ long sli;
+
+ errno = 0;
+ sli = strtol(numstr, , 0);
+ if (errno == ERANGE && (sli == LONG_MAX || sli == LONG_MIN))
+ return -ERANGE;
+
+ if (errno != 0 && sli == 0)
+ return -EINVAL;
+
+ if (err == numstr || *err != '\0')
+ return -EINVAL;
+
+ if (sli > INT_MAX || sli < INT_MIN)
+ return -ERANGE;
+
+ *converted = (int)sli;
+ return 0;
+}
+
+static int char_left_gc(const char *buffer, size_t len)
+{
+ size_t i;
+
+ for (i = 0; i < len; i++) {
+ if (buffer[i] == ' ' ||
+ buffer[i] == '\t')
+ continue;
+
+ return i;
+ }
+
+ return 0;
+}
+
+static int char_right_gc(const char *buffer, size_t len)
+{
+ int i;
+
+ for (i = len - 1; i >= 0; i--) {
+ if (buffer[i] == ' ' ||
+ buffer[i] == '\t' ||
+ buffer[i] ==
Re: [PATCH v2 1/2] pid: add pidfd_open()
On Mon, May 20, 2019 at 4:48 PM Christian Brauner wrote: > > On Mon, May 20, 2019 at 04:37:03PM +0200, Arnd Bergmann wrote: > > On Mon, May 20, 2019 at 3:46 PM Christian Brauner > > wrote: > > > > > > In line with Arnd's recent changes to consolidate syscall numbers across > > > architectures, I have added the pidfd_open() syscall to all architectures > > > at the same time. > > > > Thanks! I've checked that the ones you have added are all > > done correctly. However, double-checking that you got all of them, > > I noticed that you missed mips-o32 and mips-n64. With those added: > > > > Acked-by: Arnd Bergmann > > Perfect, will plumb mips-o32 and mips-n64 and resend once more with your > ack added. > Sidenote: You plan on merging the common syscall tables or will there be > a script to do this work per-arch in the future? David Howells also asked about this. I think having a common table will be best in the long run, patches welcome. As you noticed, there are still a few minor differences between the files on mips, arm, x86, alpha and s390, and we are missing the .tbl files for arm-compat and asm-generic, as well as an architecture independent script. Once that is all taken care of, we can move the entries for syscall 403 and higher into a common file, and change the script to pick up the contents from there in addition to the architecture specific file. Arnd
Re: [PATCH v2 1/2] pid: add pidfd_open()
On Mon, May 20, 2019 at 04:37:03PM +0200, Arnd Bergmann wrote: > On Mon, May 20, 2019 at 3:46 PM Christian Brauner > wrote: > > > > In line with Arnd's recent changes to consolidate syscall numbers across > > architectures, I have added the pidfd_open() syscall to all architectures > > at the same time. > > Thanks! I've checked that the ones you have added are all > done correctly. However, double-checking that you got all of them, > I noticed that you missed mips-o32 and mips-n64. With those added: > > Acked-by: Arnd Bergmann Perfect, will plumb mips-o32 and mips-n64 and resend once more with your ack added. Sidenote: You plan on merging the common syscall tables or will there be a script to do this work per-arch in the future?
Re: [PATCH v2 1/2] pid: add pidfd_open()
On Mon, May 20, 2019 at 3:46 PM Christian Brauner wrote: > > In line with Arnd's recent changes to consolidate syscall numbers across > architectures, I have added the pidfd_open() syscall to all architectures > at the same time. Thanks! I've checked that the ones you have added are all done correctly. However, double-checking that you got all of them, I noticed that you missed mips-o32 and mips-n64. With those added: Acked-by: Arnd Bergmann
Re: [PATCH v2 1/2] pid: add pidfd_open()
On Mon, May 20, 2019 at 3:46 PM Christian Brauner wrote:
> This adds the pidfd_open() syscall. It allows a caller to retrieve pollable
> pidfds for a process which did not get created via CLONE_PIDFD, i.e. for a
> process that is created via traditional fork()/clone() calls that is only
> referenced by a PID:
>
> int pidfd = pidfd_open(1234, 0);
> ret = pidfd_send_signal(pidfd, SIGSTOP, NULL, 0);
>
> With the introduction of pidfds through CLONE_PIDFD it is possible to
> created pidfds at process creation time.
> However, a lot of processes get created with traditional PID-based calls
> such as fork() or clone() (without CLONE_PIDFD). For these processes a
> caller can currently not create a pollable pidfd. This is a problem for
> Android's low memory killer (LMK) and service managers such as systemd.
> Both are examples of tools that want to make use of pidfds to get reliable
> notification of process exit for non-parents (pidfd polling) and race-free
> signal sending (pidfd_send_signal()). They intend to switch to this API for
> process supervision/management as soon as possible. Having no way to get
> pollable pidfds from PID-only processes is one of the biggest blockers for
> them in adopting this api. With pidfd_open() making it possible to retrieve
> pidfds for PID-based processes we enable them to adopt this api.
>
> In line with Arnd's recent changes to consolidate syscall numbers across
> architectures, I have added the pidfd_open() syscall to all architectures
> at the same time.
>
> Signed-off-by: Christian Brauner
> Reviewed-by: Oleg Nesterov
> arch/m68k/kernel/syscalls/syscall.tbl | 1 +
Acked-by: Geert Uytterhoeven
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
[PATCH v2 2/2] tests: add pidfd_open() tests
This adds testing for the new pidfd_open() syscalls. Specifically, we test:
- that no invalid flags can be passed to pidfd_open()
- that no invalid pid can be passed to pidfd_open()
- that a pidfd can be retrieved with pidfd_open()
- that the retrieved pidfd references the correct pid
Signed-off-by: Christian Brauner
Cc: Arnd Bergmann
Cc: "Eric W. Biederman"
Cc: Kees Cook
Cc: Joel Fernandes (Google)
Cc: Thomas Gleixner
Cc: Jann Horn
Cc: David Howells
Cc: "Michael Kerrisk (man-pages)"
Cc: Andy Lutomirsky
Cc: Andrew Morton
Cc: Oleg Nesterov
Cc: Aleksa Sarai
Cc: Linus Torvalds
Cc: Al Viro
Cc: linux-...@vger.kernel.org
---
v1: unchanged
v2:
- Christian Brauner :
- set number of planned tests via ksft_set_plan()
---
tools/testing/selftests/pidfd/Makefile| 2 +-
tools/testing/selftests/pidfd/pidfd.h | 57 ++
.../testing/selftests/pidfd/pidfd_open_test.c | 169 ++
tools/testing/selftests/pidfd/pidfd_test.c| 41 +
4 files changed, 228 insertions(+), 41 deletions(-)
create mode 100644 tools/testing/selftests/pidfd/pidfd.h
create mode 100644 tools/testing/selftests/pidfd/pidfd_open_test.c
diff --git a/tools/testing/selftests/pidfd/Makefile
b/tools/testing/selftests/pidfd/Makefile
index deaf8073bc06..b36c0be70848 100644
--- a/tools/testing/selftests/pidfd/Makefile
+++ b/tools/testing/selftests/pidfd/Makefile
@@ -1,6 +1,6 @@
CFLAGS += -g -I../../../../usr/include/
-TEST_GEN_PROGS := pidfd_test
+TEST_GEN_PROGS := pidfd_test pidfd_open_test
include ../lib.mk
diff --git a/tools/testing/selftests/pidfd/pidfd.h
b/tools/testing/selftests/pidfd/pidfd.h
new file mode 100644
index ..8452e910463f
--- /dev/null
+++ b/tools/testing/selftests/pidfd/pidfd.h
@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __PIDFD_H
+#define __PIDFD_H
+
+#define _GNU_SOURCE
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include "../kselftest.h"
+
+/*
+ * The kernel reserves 300 pids via RESERVED_PIDS in kernel/pid.c
+ * That means, when it wraps around any pid < 300 will be skipped.
+ * So we need to use a pid > 300 in order to test recycling.
+ */
+#define PID_RECYCLE 1000
+
+/*
+ * Define a few custom error codes for the child process to clearly indicate
+ * what is happening. This way we can tell the difference between a system
+ * error, a test error, etc.
+ */
+#define PIDFD_PASS 0
+#define PIDFD_FAIL 1
+#define PIDFD_ERROR 2
+#define PIDFD_SKIP 3
+#define PIDFD_XFAIL 4
+
+int wait_for_pid(pid_t pid)
+{
+ int status, ret;
+
+again:
+ ret = waitpid(pid, , 0);
+ if (ret == -1) {
+ if (errno == EINTR)
+ goto again;
+
+ return -1;
+ }
+
+ if (!WIFEXITED(status))
+ return -1;
+
+ return WEXITSTATUS(status);
+}
+
+
+#endif /* __PIDFD_H */
diff --git a/tools/testing/selftests/pidfd/pidfd_open_test.c
b/tools/testing/selftests/pidfd/pidfd_open_test.c
new file mode 100644
index ..0377133dd6dc
--- /dev/null
+++ b/tools/testing/selftests/pidfd/pidfd_open_test.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define _GNU_SOURCE
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#include "pidfd.h"
+#include "../kselftest.h"
+
+static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
+{
+ return syscall(__NR_pidfd_open, pid, flags);
+}
+
+static int safe_int(const char *numstr, int *converted)
+{
+ char *err = NULL;
+ long sli;
+
+ errno = 0;
+ sli = strtol(numstr, , 0);
+ if (errno == ERANGE && (sli == LONG_MAX || sli == LONG_MIN))
+ return -ERANGE;
+
+ if (errno != 0 && sli == 0)
+ return -EINVAL;
+
+ if (err == numstr || *err != '\0')
+ return -EINVAL;
+
+ if (sli > INT_MAX || sli < INT_MIN)
+ return -ERANGE;
+
+ *converted = (int)sli;
+ return 0;
+}
+
+static int char_left_gc(const char *buffer, size_t len)
+{
+ size_t i;
+
+ for (i = 0; i < len; i++) {
+ if (buffer[i] == ' ' ||
+ buffer[i] == '\t')
+ continue;
+
+ return i;
+ }
+
+ return 0;
+}
+
+static int char_right_gc(const char *buffer, size_t len)
+{
+ int i;
+
+ for (i = len - 1; i >= 0; i--) {
+ if (buffer[i] == ' ' ||
+ buffer[i] == '\t' ||
+ buffer[i] == '\n' ||
+ buffer[i] == '\0')
+ continue;
+
+ return i + 1;
+ }
+
+ return 0;
+}
+
+static char *trim_whitespace_in_place(char *buffer)
+{
+ buffer += char_left_gc(buffer, strlen(buffer));
+ buffer[char_right_gc(buffer, strlen(buffer))] = '\0';
+ return buffer;
[PATCH v2 1/2] pid: add pidfd_open()
This adds the pidfd_open() syscall. It allows a caller to retrieve pollable pidfds for a process which did not get created via CLONE_PIDFD, i.e. for a process that is created via traditional fork()/clone() calls that is only referenced by a PID: int pidfd = pidfd_open(1234, 0); ret = pidfd_send_signal(pidfd, SIGSTOP, NULL, 0); With the introduction of pidfds through CLONE_PIDFD it is possible to created pidfds at process creation time. However, a lot of processes get created with traditional PID-based calls such as fork() or clone() (without CLONE_PIDFD). For these processes a caller can currently not create a pollable pidfd. This is a problem for Android's low memory killer (LMK) and service managers such as systemd. Both are examples of tools that want to make use of pidfds to get reliable notification of process exit for non-parents (pidfd polling) and race-free signal sending (pidfd_send_signal()). They intend to switch to this API for process supervision/management as soon as possible. Having no way to get pollable pidfds from PID-only processes is one of the biggest blockers for them in adopting this api. With pidfd_open() making it possible to retrieve pidfds for PID-based processes we enable them to adopt this api. In line with Arnd's recent changes to consolidate syscall numbers across architectures, I have added the pidfd_open() syscall to all architectures at the same time. Signed-off-by: Christian Brauner Reviewed-by: Oleg Nesterov Cc: Arnd Bergmann Cc: "Eric W. Biederman" Cc: Kees Cook Cc: Joel Fernandes (Google) Cc: Thomas Gleixner Cc: Jann Horn Cc: David Howells Cc: Andy Lutomirsky Cc: Andrew Morton Cc: Aleksa Sarai Cc: Linus Torvalds Cc: Al Viro Cc: linux-...@vger.kernel.org --- v1: - kbuild test robot : - add missing entry for pidfd_open to arch/arm/tools/syscall.tbl - Oleg Nesterov : - use simpler thread-group leader check v2: - Oleg Nesterov : - avoid using additional variable - remove unneeded comment - Arnd Bergmann : - switch from 428 to 434 since the new mount api has taken it - bump syscall numbers in arch/arm64/include/asm/unistd.h - Joel Fernandes (Google) : - switch from ESRCH to EINVAL when the passed-in pid does not refer to a thread-group leader - Christian Brauner : - rebase on v5.2-rc1 - adapt syscall number to account for new mount api syscalls --- arch/alpha/kernel/syscalls/syscall.tbl | 1 + arch/arm/tools/syscall.tbl | 1 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 2 + arch/ia64/kernel/syscalls/syscall.tbl | 1 + arch/m68k/kernel/syscalls/syscall.tbl | 1 + arch/microblaze/kernel/syscalls/syscall.tbl | 1 + arch/mips/kernel/syscalls/syscall_n32.tbl | 1 + arch/parisc/kernel/syscalls/syscall.tbl | 1 + arch/powerpc/kernel/syscalls/syscall.tbl| 1 + arch/s390/kernel/syscalls/syscall.tbl | 1 + arch/sh/kernel/syscalls/syscall.tbl | 1 + arch/sparc/kernel/syscalls/syscall.tbl | 1 + arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + arch/xtensa/kernel/syscalls/syscall.tbl | 1 + include/linux/pid.h | 1 + include/linux/syscalls.h| 1 + include/uapi/asm-generic/unistd.h | 4 +- kernel/fork.c | 2 +- kernel/pid.c| 43 + 21 files changed, 66 insertions(+), 3 deletions(-) diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index 9e7704e44f6d..1db9bbcfb84e 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -473,3 +473,4 @@ 541common fsconfigsys_fsconfig 542common fsmount sys_fsmount 543common fspick sys_fspick +544common pidfd_open sys_pidfd_open diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index aaf479a9e92d..81e6e1817c45 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -447,3 +447,4 @@ 431common fsconfigsys_fsconfig 432common fsmount sys_fsmount 433common fspick sys_fspick +434common pidfd_open sys_pidfd_open diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index 70e6882853c0..e8f7d95a1481 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -44,7 +44,7 @@ #define __ARM_NR_compat_set_tls(__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END(__ARM_NR_COMPAT_BASE + 0x800) -#define __NR_compat_syscalls 434 +#define __NR_compat_syscalls 435 #endif #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h
