[PATCH v4 0/4] selftests/mm: refactor pkey helpers and fix mmap error handling

[PATCH v4 0/4] selftests/mm: refactor pkey helpers and fix mmap error handling

[Hongfu Li]

The main changes in this series are to refactor shared tracing and assertion
helpers into a common file, unify both pkey selftests on pkey_assert() and 
per-test tracing for consistent diagnostics, and add missing mmap() return 
checks with MAP_FAILED used throughout for readability and consistency.

Hongfu Li (4):
  selftests/mm: move pkey selftest helpers to pkey_util.c
  selftests/mm: unify pkey sighandler selftest assertions and tracing
  selftests/mm: use pkey_assert on clone_raw failure in pkey test
  selftests/mm: add missing mmap() return checks in pkey tests

 tools/testing/selftests/mm/pkey-helpers.h     |   5 +-
 tools/testing/selftests/mm/pkey-powerpc.h     |   2 +-
 .../selftests/mm/pkey_sighandler_tests.c      | 110 +++++++++---------
 tools/testing/selftests/mm/pkey_util.c        |  86 ++++++++++++++
 tools/testing/selftests/mm/protection_keys.c  |  95 ++-------------
 5 files changed, 152 insertions(+), 146 deletions(-)

---
v4:
- Base changes on top of the latest mm-unstable branch.
- Split the first patch into three:
  patch 1: move pkey selftest helpers to shared code;
  patch 2: unify sighandler selftest assertions and per-test tracing;
  patch 3: use pkey_assert() on clone_raw() failure.
- Use ksft_exit_fail_perror() in main() for mmap() failure.
v3:
- Use pkey_assert() for remaining sigaction() and clone_raw() error
  checks for consistency.
v2:
- Update commit message
- Move shared tracing and assertion helpers to a common file,
  replace assert() with pkey_assert() in sighandler tests
- Drop assert() from main() in protection_keys.c and add a proper error
  message instead.
- Link to v1: https://lore.kernel.org/all/20260518082120.3890552-1-lihongfu@kylinos.cn/
-- 
2.50.1

[PATCH v4 1/4] selftests/mm: move pkey selftest helpers to pkey_util.c

[Hongfu Li]

Move pkey selftest debugging helpers into shared code so both pkey
selftests can use the same tracing and abort-hook logic.

Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
---
 tools/testing/selftests/mm/pkey-helpers.h    |  5 +-
 tools/testing/selftests/mm/pkey_util.c       | 86 ++++++++++++++++++++
 tools/testing/selftests/mm/protection_keys.c | 83 -------------------
 3 files changed, 90 insertions(+), 84 deletions(-)

diff --git a/tools/testing/selftests/mm/pkey-helpers.h b/tools/testing/selftests/mm/pkey-helpers.h
index 2c377f4e9df1..cfbb8fa2af3c 100644
--- a/tools/testing/selftests/mm/pkey-helpers.h
+++ b/tools/testing/selftests/mm/pkey-helpers.h
@@ -68,7 +68,10 @@ static inline void sigsafe_printf(const char *format, ...)
 #define dprintf3(args...) dprintf_level(3, args)
 #define dprintf4(args...) dprintf_level(4, args)
 
-extern void abort_hooks(void);
+void cat_into_file(char *str, char *file);
+void tracing_on(void);
+void tracing_off(void);
+void abort_hooks(void);
 #define pkey_assert(condition) do {		\
 	if (!(condition)) {			\
 		dprintf0("# assert() at %s::%d test_nr: %d iteration: %d\n", \
diff --git a/tools/testing/selftests/mm/pkey_util.c b/tools/testing/selftests/mm/pkey_util.c
index 255b332f7a08..81723db43223 100644
--- a/tools/testing/selftests/mm/pkey_util.c
+++ b/tools/testing/selftests/mm/pkey_util.c
@@ -2,9 +2,95 @@
 #define __SANE_USERSPACE_TYPES__
 #include <sys/syscall.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <string.h>
 
 #include "pkey-helpers.h"
 
+#if CONTROL_TRACING > 0
+static void cat_into_file(char *str, char *file)
+{
+	int fd = open(file, O_RDWR);
+	int ret;
+
+	dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
+	/*
+	 * these need to be raw because they are called under
+	 * pkey_assert()
+	 */
+	if (fd < 0) {
+		fprintf(stderr, "error opening '%s'\n", str);
+		perror("error: ");
+		exit(__LINE__);
+	}
+
+	ret = write(fd, str, strlen(str));
+	if (ret != strlen(str)) {
+		perror("write to file failed");
+		fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
+		exit(__LINE__);
+	}
+	close(fd);
+}
+
+static int warned_tracing;
+static int tracing_root_ok(void)
+{
+	if (geteuid() != 0) {
+		if (!warned_tracing)
+			fprintf(stderr, "WARNING: not run as root, "
+					"can not do tracing control\n");
+		warned_tracing = 1;
+		return 0;
+	}
+	return 1;
+}
+#endif
+
+static void tracing_on(void)
+{
+#if CONTROL_TRACING > 0
+#define TRACEDIR "/sys/kernel/tracing"
+	char pidstr[32];
+
+	if (!tracing_root_ok())
+		return;
+
+	sprintf(pidstr, "%d", getpid());
+	cat_into_file("0", TRACEDIR "/tracing_on");
+	cat_into_file("\n", TRACEDIR "/trace");
+	if (1) {
+		cat_into_file("function_graph", TRACEDIR "/current_tracer");
+		cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
+	} else {
+		cat_into_file("nop", TRACEDIR "/current_tracer");
+	}
+	cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
+	cat_into_file("1", TRACEDIR "/tracing_on");
+	dprintf1("enabled tracing\n");
+#endif
+}
+
+static void tracing_off(void)
+{
+#if CONTROL_TRACING > 0
+	if (!tracing_root_ok())
+		return;
+	cat_into_file("0", "/sys/kernel/tracing/tracing_on");
+#endif
+}
+
+void abort_hooks(void)
+{
+	fflush(stdout);
+	fprintf(stderr, "running %s()...\n", __func__);
+	tracing_off();
+#ifdef SLEEP_ON_ABORT
+	sleep(SLEEP_ON_ABORT);
+#endif
+}
+
 int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
 {
 	int ret = syscall(SYS_pkey_alloc, flags, init_val);
diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c
index 9a6d954ee371..e504544e2197 100644
--- a/tools/testing/selftests/mm/protection_keys.c
+++ b/tools/testing/selftests/mm/protection_keys.c
@@ -62,89 +62,6 @@ noinline int read_ptr(int *ptr)
 	return *ptr;
 }
 
-#if CONTROL_TRACING > 0
-static void cat_into_file(char *str, char *file)
-{
-	int fd = open(file, O_RDWR);
-	int ret;
-
-	dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
-	/*
-	 * these need to be raw because they are called under
-	 * pkey_assert()
-	 */
-	if (fd < 0) {
-		fprintf(stderr, "error opening '%s'\n", str);
-		perror("error: ");
-		exit(__LINE__);
-	}
-
-	ret = write(fd, str, strlen(str));
-	if (ret != strlen(str)) {
-		perror("write to file failed");
-		fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
-		exit(__LINE__);
-	}
-	close(fd);
-}
-
-static int warned_tracing;
-static int tracing_root_ok(void)
-{
-	if (geteuid() != 0) {
-		if (!warned_tracing)
-			fprintf(stderr, "WARNING: not run as root, "
-					"can not do tracing control\n");
-		warned_tracing = 1;
-		return 0;
-	}
-	return 1;
-}
-#endif
-
-static void tracing_on(void)
-{
-#if CONTROL_TRACING > 0
-#define TRACEDIR "/sys/kernel/tracing"
-	char pidstr[32];
-
-	if (!tracing_root_ok())
-		return;
-
-	sprintf(pidstr, "%d", getpid());
-	cat_into_file("0", TRACEDIR "/tracing_on");
-	cat_into_file("\n", TRACEDIR "/trace");
-	if (1) {
-		cat_into_file("function_graph", TRACEDIR "/current_tracer");
-		cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
-	} else {
-		cat_into_file("nop", TRACEDIR "/current_tracer");
-	}
-	cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
-	cat_into_file("1", TRACEDIR "/tracing_on");
-	dprintf1("enabled tracing\n");
-#endif
-}
-
-static void tracing_off(void)
-{
-#if CONTROL_TRACING > 0
-	if (!tracing_root_ok())
-		return;
-	cat_into_file("0", "/sys/kernel/tracing/tracing_on");
-#endif
-}
-
-void abort_hooks(void)
-{
-	fflush(stdout);
-	fprintf(stderr, "running %s()...\n", __func__);
-	tracing_off();
-#ifdef SLEEP_ON_ABORT
-	sleep(SLEEP_ON_ABORT);
-#endif
-}
-
 /*
  * This attempts to have roughly a page of instructions followed by a few
  * instructions that do a write, and another page of instructions.  That
-- 
2.50.1

Re: [PATCH v4 1/4] selftests/mm: move pkey selftest helpers to pkey_util.c

[Hongfu Li]

>  #include <sys/syscall.h>
>  #include <unistd.h>
> +#include <fcntl.h>
> +#include <stdio.h>
> +#include <string.h>
>  
>  #include "pkey-helpers.h"
>  
> +#if CONTROL_TRACING > 0
> +static void cat_into_file(char *str, char *file)

Sorry, I sent the wrong patch file by mistake.

There are three issues in the current patch: the three new functions
in pkey_util.c (cat_into_file, tracing_on and tracing_off) should be
 defined as non-static. I will fix all of them in a later version.

Please ignore these three issues during review.

[PATCH v4 2/4] selftests/mm: unify pkey sighandler selftest assertions and tracing

[Hongfu Li]

Add per-test tracing to the pkey signal-handler selftest and use
pkey_assert() for error handling. Each test enables tracing at start
and disables it at end; on failure, pkey_assert() calls abort_hooks()
to turn tracing off so ftrace is not left enabled.

Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
---
 .../selftests/mm/pkey_sighandler_tests.c      | 104 +++++++++---------
 1 file changed, 50 insertions(+), 54 deletions(-)

diff --git a/tools/testing/selftests/mm/pkey_sighandler_tests.c b/tools/testing/selftests/mm/pkey_sighandler_tests.c
index 302fef54049c..80b5b3dad86f 100644
--- a/tools/testing/selftests/mm/pkey_sighandler_tests.c
+++ b/tools/testing/selftests/mm/pkey_sighandler_tests.c
@@ -19,7 +19,6 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <signal.h>
-#include <assert.h>
 #include <stdlib.h>
 #include <sys/mman.h>
 #include <sys/types.h>
@@ -36,6 +35,10 @@ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
 static siginfo_t siginfo = {0};
 
+int iteration_nr = 1;
+int test_nr;
+int dprint_in_signal;
+
 /*
  * We need to use inline assembly instead of glibc's syscall because glibc's
  * syscall will attempt to access the PLT in order to call a library function
@@ -207,15 +210,14 @@ static void test_sigsegv_handler_with_pkey0_disabled(void)
 	struct sigaction sa;
 	pthread_attr_t attr;
 	pthread_t thr;
+	int ret;
 
 	sa.sa_flags = SA_SIGINFO;
 
 	sa.sa_sigaction = sigsegv_handler;
 	sigemptyset(&sa.sa_mask);
-	if (sigaction(SIGSEGV, &sa, NULL) == -1) {
-		perror("sigaction");
-		exit(EXIT_FAILURE);
-	}
+	ret = sigaction(SIGSEGV, &sa, NULL);
+	pkey_assert(ret == 0);
 
 	memset(&siginfo, 0, sizeof(siginfo));
 
@@ -247,15 +249,14 @@ static void test_sigsegv_handler_cannot_access_stack(void)
 	struct sigaction sa;
 	pthread_attr_t attr;
 	pthread_t thr;
+	int ret;
 
 	sa.sa_flags = SA_SIGINFO;
 
 	sa.sa_sigaction = sigsegv_handler;
 	sigemptyset(&sa.sa_mask);
-	if (sigaction(SIGSEGV, &sa, NULL) == -1) {
-		perror("sigaction");
-		exit(EXIT_FAILURE);
-	}
+	ret = sigaction(SIGSEGV, &sa, NULL);
+	pkey_assert(ret == 0);
 
 	memset(&siginfo, 0, sizeof(siginfo));
 
@@ -288,21 +289,20 @@ static void test_sigsegv_handler_with_different_pkey_for_stack(void)
 	int parent_pid = 0;
 	int child_pid = 0;
 	u64 pkey_reg;
+	int ret;
 
 	sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
 
 	sa.sa_sigaction = sigsegv_handler;
 
 	sigemptyset(&sa.sa_mask);
-	if (sigaction(SIGSEGV, &sa, NULL) == -1) {
-		perror("sigaction");
-		exit(EXIT_FAILURE);
-	}
+	ret = sigaction(SIGSEGV, &sa, NULL);
+	pkey_assert(ret == 0);
 
 	stack = mmap(0, STACK_SIZE, PROT_READ | PROT_WRITE,
 		     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 
-	assert(stack != MAP_FAILED);
+	pkey_assert(stack != MAP_FAILED);
 
 	/* Allow access to MPK 0 and MPK 1 */
 	pkey_reg = pkey_reg_restrictive_default();
@@ -323,18 +323,18 @@ static void test_sigsegv_handler_with_different_pkey_for_stack(void)
 	memset(&siginfo, 0, sizeof(siginfo));
 
 	/* Use clone to avoid newer glibcs using rseq on new threads */
-	long ret = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
-			     CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
-			     CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
-			     CLONE_DETACHED,
-			     stack + STACK_SIZE,
-			     &parent_pid,
-			     &child_pid);
-
-	if (ret < 0) {
-		errno = -ret;
+	child_pid = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
+			      CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
+			      CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
+			      CLONE_DETACHED,
+			      stack + STACK_SIZE,
+			      &parent_pid,
+			      &child_pid);
+
+	if (child_pid < 0) {
+		errno = -child_pid;
 		perror("clone");
-	} else if (ret == 0) {
+	} else if (child_pid == 0) {
 		thread_segv_maperr_ptr(&sigstack);
 		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
 	}
@@ -358,6 +358,7 @@ static void test_pkru_preserved_after_sigusr1(void)
 {
 	struct sigaction sa;
 	u64 pkey_reg;
+	int ret;
 
 	/* Allow access to MPK 0 and an arbitrary set of keys */
 	pkey_reg = pkey_reg_restrictive_default();
@@ -369,10 +370,8 @@ static void test_pkru_preserved_after_sigusr1(void)
 
 	sa.sa_sigaction = sigusr1_handler;
 	sigemptyset(&sa.sa_mask);
-	if (sigaction(SIGUSR1, &sa, NULL) == -1) {
-		perror("sigaction");
-		exit(EXIT_FAILURE);
-	}
+	ret = sigaction(SIGUSR1, &sa, NULL);
+	pkey_assert(ret == 0);
 
 	memset(&siginfo, 0, sizeof(siginfo));
 
@@ -444,6 +443,7 @@ static void test_pkru_sigreturn(void)
 	int parent_pid = 0;
 	int child_pid = 0;
 	u64 pkey_reg;
+	int ret;
 
 	sa.sa_handler = SIG_DFL;
 	sa.sa_flags = 0;
@@ -453,24 +453,20 @@ static void test_pkru_sigreturn(void)
 	 * For this testcase, we do not want to handle SIGSEGV. Reset handler
 	 * to default so that the application can crash if it receives SIGSEGV.
 	 */
-	if (sigaction(SIGSEGV, &sa, NULL) == -1) {
-		perror("sigaction");
-		exit(EXIT_FAILURE);
-	}
+	ret = sigaction(SIGSEGV, &sa, NULL);
+	pkey_assert(ret == 0);
 
 	sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
 	sa.sa_sigaction = sigusr2_handler;
 	sigemptyset(&sa.sa_mask);
 
-	if (sigaction(SIGUSR2, &sa, NULL) == -1) {
-		perror("sigaction");
-		exit(EXIT_FAILURE);
-	}
+	ret = sigaction(SIGUSR2, &sa, NULL);
+	pkey_assert(ret == 0);
 
 	stack = mmap(0, STACK_SIZE, PROT_READ | PROT_WRITE,
 		     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 
-	assert(stack != MAP_FAILED);
+	pkey_assert(stack != MAP_FAILED);
 
 	/*
 	 * Allow access to MPK 0 and MPK 2. The child thread (to be created
@@ -494,23 +490,22 @@ static void test_pkru_sigreturn(void)
 	sigstack.ss_size = STACK_SIZE;
 
 	/* Use clone to avoid newer glibcs using rseq on new threads */
-	long ret = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
-			     CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
-			     CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
-			     CLONE_DETACHED,
-			     stack + STACK_SIZE,
-			     &parent_pid,
-			     &child_pid);
-
-	if (ret < 0) {
-		errno = -ret;
+	child_pid = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
+			      CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
+			      CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
+			      CLONE_DETACHED,
+			      stack + STACK_SIZE,
+			      &parent_pid,
+			      &child_pid);
+
+	if (child_pid < 0) {
+		errno = -child_pid;
 		perror("clone");
-	}  else if (ret == 0) {
+	} else if (child_pid == 0) {
 		thread_sigusr2_self(&sigstack);
 		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
 	}
 
-	child_pid =  ret;
 	/* Check that thread exited */
 	do {
 		sched_yield();
@@ -530,16 +525,17 @@ static void (*pkey_tests[])(void) = {
 
 int main(int argc, char *argv[])
 {
-	int i;
-
 	ksft_print_header();
 	ksft_set_plan(ARRAY_SIZE(pkey_tests));
 
 	if (!is_pkeys_supported())
 		ksft_exit_skip("pkeys not supported\n");
 
-	for (i = 0; i < ARRAY_SIZE(pkey_tests); i++)
-		(*pkey_tests[i])();
+	for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
+		tracing_on();
+		(*pkey_tests[test_nr])();
+		tracing_off();
+	}
 
 	ksft_finished();
 	return 0;
-- 
2.50.1

Re: [PATCH v4 2/4] selftests/mm: unify pkey sighandler selftest assertions and tracing

[Mike Rapoport]

Hi,

On Fri, May 29, 2026 at 03:16:31PM +0800, Hongfu Li wrote:
> Add per-test tracing to the pkey signal-handler selftest and use
> pkey_assert() for error handling. Each test enables tracing at start
> and disables it at end; on failure, pkey_assert() calls abort_hooks()
> to turn tracing off so ftrace is not left enabled.
> 
> Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
> ---
>  .../selftests/mm/pkey_sighandler_tests.c      | 104 +++++++++---------
>  1 file changed, 50 insertions(+), 54 deletions(-)
>
> @@ -323,18 +323,18 @@ static void test_sigsegv_handler_with_different_pkey_for_stack(void)
>  	memset(&siginfo, 0, sizeof(siginfo));
>  
>  	/* Use clone to avoid newer glibcs using rseq on new threads */
> -	long ret = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
> -			     CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
> -			     CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
> -			     CLONE_DETACHED,
> -			     stack + STACK_SIZE,
> -			     &parent_pid,
> -			     &child_pid);
> -
> -	if (ret < 0) {
> -		errno = -ret;
> +	child_pid = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
> +			      CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
> +			      CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
> +			      CLONE_DETACHED,
> +			      stack + STACK_SIZE,
> +			      &parent_pid,
> +			      &child_pid);
> +
> +	if (child_pid < 0) {
> +		errno = -child_pid;

This change does not seem related at all to the patch.

>  		perror("clone");
> -	} else if (ret == 0) {
> +	} else if (child_pid == 0) {
>  		thread_segv_maperr_ptr(&sigstack);
>  		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
>  	}
>
> @@ -494,23 +490,22 @@ static void test_pkru_sigreturn(void)
>  	sigstack.ss_size = STACK_SIZE;
>  
>  	/* Use clone to avoid newer glibcs using rseq on new threads */
> -	long ret = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
> -			     CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
> -			     CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
> -			     CLONE_DETACHED,
> -			     stack + STACK_SIZE,
> -			     &parent_pid,
> -			     &child_pid);
> -
> -	if (ret < 0) {
> -		errno = -ret;
> +	child_pid = clone_raw(CLONE_VM | CLONE_FS | CLONE_FILES |
> +			      CLONE_SIGHAND | CLONE_THREAD | CLONE_SYSVSEM |
> +			      CLONE_PARENT_SETTID | CLONE_CHILD_CLEARTID |
> +			      CLONE_DETACHED,
> +			      stack + STACK_SIZE,
> +			      &parent_pid,
> +			      &child_pid);
> +
> +	if (child_pid < 0) {
> +		errno = -child_pid;

Ditto.

>  		perror("clone");
> -	}  else if (ret == 0) {
> +	} else if (child_pid == 0) {
>  		thread_sigusr2_self(&sigstack);
>  		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
>  	}
>  
> -	child_pid =  ret;
>  	/* Check that thread exited */
>  	do {
>  		sched_yield();

-- 
Sincerely yours,
Mike.

[PATCH v4 3/4] selftests/mm: use pkey_assert on clone_raw failure in pkey test

[Hongfu Li]

Use pkey_assert(0) instead of perror("clone") when clone_raw() fails.
The old path only printed an error and continued; the test now exits
via pkey_assert() on failure so it does not hang or proceed with an
invalid child.

Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
---
 tools/testing/selftests/mm/pkey_sighandler_tests.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/mm/pkey_sighandler_tests.c b/tools/testing/selftests/mm/pkey_sighandler_tests.c
index 80b5b3dad86f..231dfb079075 100644
--- a/tools/testing/selftests/mm/pkey_sighandler_tests.c
+++ b/tools/testing/selftests/mm/pkey_sighandler_tests.c
@@ -333,7 +333,7 @@ static void test_sigsegv_handler_with_different_pkey_for_stack(void)
 
 	if (child_pid < 0) {
 		errno = -child_pid;
-		perror("clone");
+		pkey_assert(0);
 	} else if (child_pid == 0) {
 		thread_segv_maperr_ptr(&sigstack);
 		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
@@ -500,7 +500,7 @@ static void test_pkru_sigreturn(void)
 
 	if (child_pid < 0) {
 		errno = -child_pid;
-		perror("clone");
+		pkey_assert(0);
 	} else if (child_pid == 0) {
 		thread_sigusr2_self(&sigstack);
 		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
-- 
2.50.1

Re: [PATCH v4 3/4] selftests/mm: use pkey_assert on clone_raw failure in pkey test

[Mike Rapoport]

Hi,

On Fri, May 29, 2026 at 03:16:32PM +0800, Hongfu Li wrote:
> Use pkey_assert(0) instead of perror("clone") when clone_raw() fails.
> The old path only printed an error and continued; the test now exits
> via pkey_assert() on failure so it does not hang or proceed with an
> invalid child.

Looks like clone() invocation changes in patch 2 belong here.
But is there actually a need to change ret = clone_raw() to
child_pid = clone_raw()?
 
> Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
> ---
>  tools/testing/selftests/mm/pkey_sighandler_tests.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/mm/pkey_sighandler_tests.c b/tools/testing/selftests/mm/pkey_sighandler_tests.c
> index 80b5b3dad86f..231dfb079075 100644
> --- a/tools/testing/selftests/mm/pkey_sighandler_tests.c
> +++ b/tools/testing/selftests/mm/pkey_sighandler_tests.c
> @@ -333,7 +333,7 @@ static void test_sigsegv_handler_with_different_pkey_for_stack(void)
>  
>  	if (child_pid < 0) {
>  		errno = -child_pid;
> -		perror("clone");
> +		pkey_assert(0);
>  	} else if (child_pid == 0) {
>  		thread_segv_maperr_ptr(&sigstack);
>  		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
> @@ -500,7 +500,7 @@ static void test_pkru_sigreturn(void)
>  
>  	if (child_pid < 0) {
>  		errno = -child_pid;
> -		perror("clone");
> +		pkey_assert(0);
>  	} else if (child_pid == 0) {
>  		thread_sigusr2_self(&sigstack);
>  		syscall_raw(SYS_exit, 0, 0, 0, 0, 0, 0);
> -- 
> 2.50.1
> 

-- 
Sincerely yours,
Mike.

Re: [PATCH v4 3/4] selftests/mm: use pkey_assert on clone_raw failure in pkey test

[Hongfu Li]

Hi,

> > Use pkey_assert(0) instead of perror("clone") when clone_raw() fails.
> > The old path only printed an error and continued; the test now exits
> > via pkey_assert() on failure so it does not hang or proceed with an
> > invalid child.
> 
> Looks like clone() invocation changes in patch 2 belong here.
> But is there actually a need to change ret = clone_raw() to
> child_pid = clone_raw()?

You're right. This variable change seems pointless, and I'll revert
it in the next patch version.

[PATCH v4 4/4] selftests/mm: add missing mmap() return checks in pkey tests

[Hongfu Li]

Add missing checks against mmap() return value, replace (void *)-1
with MAP_FAILED for better readability and consistency.

Signed-off-by: Hongfu Li <lihongfu@kylinos.cn>
---
 tools/testing/selftests/mm/pkey-powerpc.h          |  2 +-
 tools/testing/selftests/mm/pkey_sighandler_tests.c |  2 ++
 tools/testing/selftests/mm/protection_keys.c       | 12 +++++++-----
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/mm/pkey-powerpc.h b/tools/testing/selftests/mm/pkey-powerpc.h
index 17bf2d1b0192..2ce85580b404 100644
--- a/tools/testing/selftests/mm/pkey-powerpc.h
+++ b/tools/testing/selftests/mm/pkey-powerpc.h
@@ -126,7 +126,7 @@ static inline void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 p
 			size, prot, pkey);
 	pkey_assert(pkey < NR_PKEYS);
 	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-	pkey_assert(ptr != (void *)-1);
+	pkey_assert(ptr != MAP_FAILED);
 
 	ret = syscall(__NR_subpage_prot, ptr, size, NULL);
 	if (ret) {
diff --git a/tools/testing/selftests/mm/pkey_sighandler_tests.c b/tools/testing/selftests/mm/pkey_sighandler_tests.c
index 231dfb079075..475aa3e3208a 100644
--- a/tools/testing/selftests/mm/pkey_sighandler_tests.c
+++ b/tools/testing/selftests/mm/pkey_sighandler_tests.c
@@ -317,6 +317,7 @@ static void test_sigsegv_handler_with_different_pkey_for_stack(void)
 	/* Set up alternate signal stack that will use the default MPK */
 	sigstack.ss_sp = mmap(0, STACK_SIZE, PROT_READ | PROT_WRITE,
 			      MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	pkey_assert(sigstack.ss_sp != MAP_FAILED);
 	sigstack.ss_flags = 0;
 	sigstack.ss_size = STACK_SIZE;
 
@@ -486,6 +487,7 @@ static void test_pkru_sigreturn(void)
 	/* Set up alternate signal stack that will use the default MPK */
 	sigstack.ss_sp = mmap(0, STACK_SIZE, PROT_READ | PROT_WRITE,
 			      MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+	pkey_assert(sigstack.ss_sp != MAP_FAILED);
 	sigstack.ss_flags = 0;
 	sigstack.ss_size = STACK_SIZE;
 
diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c
index e504544e2197..96a4eb26f326 100644
--- a/tools/testing/selftests/mm/protection_keys.c
+++ b/tools/testing/selftests/mm/protection_keys.c
@@ -586,7 +586,7 @@ static void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
 			size, prot, pkey);
 	pkey_assert(pkey < NR_PKEYS);
 	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-	pkey_assert(ptr != (void *)-1);
+	pkey_assert(ptr != MAP_FAILED);
 	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
 	pkey_assert(!ret);
 	record_pkey_malloc(ptr, size, prot);
@@ -609,7 +609,7 @@ static void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
 	 */
 	size = ALIGN_UP(size, HPAGE_SIZE * 2);
 	ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-	pkey_assert(ptr != (void *)-1);
+	pkey_assert(ptr != MAP_FAILED);
 	record_pkey_malloc(ptr, size, prot);
 	mprotect_pkey(ptr, size, prot, pkey);
 
@@ -667,7 +667,7 @@ static void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
 	size = ALIGN_UP(size, HPAGE_SIZE * 2);
 	pkey_assert(pkey < NR_PKEYS);
 	ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
-	pkey_assert(ptr != (void *)-1);
+	pkey_assert(ptr != MAP_FAILED);
 	mprotect_pkey(ptr, size, prot, pkey);
 
 	record_pkey_malloc(ptr, size, prot);
@@ -696,7 +696,7 @@ static void *malloc_pkey(long size, int prot, u16 pkey)
 		pkey_assert(malloc_type < nr_malloc_types);
 
 		ret = pkey_malloc[malloc_type](size, prot, pkey);
-		pkey_assert(ret != (void *)-1);
+		pkey_assert(ret != MAP_FAILED);
 
 		malloc_type++;
 		if (malloc_type >= nr_malloc_types)
@@ -1114,6 +1114,7 @@ static void arch_force_pkey_reg_init(void)
 	 * doing the XSAVE size enumeration dance.
 	 */
 	buf = mmap(NULL, 1*MB, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+	pkey_assert(buf != MAP_FAILED);
 
 	/* These __builtins require compiling with -mxsave */
 
@@ -1680,7 +1681,8 @@ int main(void)
 		ksft_print_msg("running PKEY tests for unsupported CPU/OS\n");
 
 		ptr  = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
-		assert(ptr != (void *)-1);
+		if (ptr == MAP_FAILED)
+			ksft_exit_fail_perror("mmap");
 		test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
 		ksft_test_result_pass("pkey on unsupported CPU/OS\n");
 		ksft_finished();
-- 
2.50.1