* [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
@ 2026-02-19 22:50 Ricardo Branco
2026-02-20 10:41 ` Cyril Hrubis
2026-02-20 15:32 ` Andrea Cervesato via ltp
0 siblings, 2 replies; 8+ messages in thread
From: Ricardo Branco @ 2026-02-19 22:50 UTC (permalink / raw)
To: ltp
Signed-off-by: Ricardo Branco <rbranco@suse.de>
---
configure.ac | 1 +
include/lapi/userfaultfd.h | 13 ++
.../kernel/syscalls/userfaultfd/.gitignore | 1 +
.../kernel/syscalls/userfaultfd/Makefile | 1 +
.../syscalls/userfaultfd/userfaultfd06.c | 137 ++++++++++++++++++
5 files changed, 153 insertions(+)
create mode 100644 testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
diff --git a/configure.ac b/configure.ac
index 7fa614dcb..94bcbcc98 100644
--- a/configure.ac
+++ b/configure.ac
@@ -278,6 +278,7 @@ AC_CHECK_TYPES([struct sockaddr_vm],,,[
])
AC_CHECK_TYPES([struct uffdio_move],,,[#include <linux/userfaultfd.h>])
+AC_CHECK_TYPES([struct uffdio_poison],,,[#include <linux/userfaultfd.h>])
AC_CHECK_TYPES([struct uffdio_writeprotect],,,[#include <linux/userfaultfd.h>])
# Tools knobs
diff --git a/include/lapi/userfaultfd.h b/include/lapi/userfaultfd.h
index 0c9e34c84..aab3890b7 100644
--- a/include/lapi/userfaultfd.h
+++ b/include/lapi/userfaultfd.h
@@ -233,6 +233,19 @@ struct uffdio_writeprotect {
};
#endif /* HAVE_STRUCT_UFFDIO_WRITEPROTECT */
+#ifndef HAVE_STRUCT_UFFDIO_POISON
+#define UFFD_FEATURE_POISON (1<<14)
+#define _UFFDIO_POISON (0x08)
+#define UFFDIO_POISON _IOWR(UFFDIO, _UFFDIO_POISON, \
+ struct uffdio_poison)
+struct uffdio_poison {
+ struct uffdio_range range;
+#define UFFDIO_POISON_MODE_DONTWAKE ((__u64)1<<0)
+ __u64 mode;
+ __s64 updated;
+};
+#endif /* HAVE_STRUCT_UFFDIO_POISON */
+
#define SAFE_USERFAULTFD(flags, retry) \
safe_userfaultfd(__FILE__, __LINE__, (flags), (retry))
diff --git a/testcases/kernel/syscalls/userfaultfd/.gitignore b/testcases/kernel/syscalls/userfaultfd/.gitignore
index fb2ae243b..bc32fdf3b 100644
--- a/testcases/kernel/syscalls/userfaultfd/.gitignore
+++ b/testcases/kernel/syscalls/userfaultfd/.gitignore
@@ -3,3 +3,4 @@
/userfaultfd03
/userfaultfd04
/userfaultfd05
+/userfaultfd06
diff --git a/testcases/kernel/syscalls/userfaultfd/Makefile b/testcases/kernel/syscalls/userfaultfd/Makefile
index 96650a65a..3252e47df 100644
--- a/testcases/kernel/syscalls/userfaultfd/Makefile
+++ b/testcases/kernel/syscalls/userfaultfd/Makefile
@@ -16,3 +16,4 @@ userfaultfd02: CFLAGS += -pthread
userfaultfd03: CFLAGS += -pthread
userfaultfd04: CFLAGS += -pthread
userfaultfd05: CFLAGS += -pthread
+userfaultfd06: CFLAGS += -pthread
diff --git a/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c b/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
new file mode 100644
index 000000000..1f132d4d5
--- /dev/null
+++ b/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2026 SUSE LLC
+ * Author: Ricardo Branco <rbranco@suse.com>
+ */
+
+/*\
+ * Force a pagefault event and handle it using :manpage:`userfaultfd(2)`
+ * from a different thread testing UFFDIO_POISON.
+ */
+
+#include "config.h"
+#include <poll.h>
+#include <setjmp.h>
+#include <signal.h>
+#include <unistd.h>
+#include "tst_test.h"
+#include "tst_safe_macros.h"
+#include "tst_safe_pthread.h"
+#include "lapi/userfaultfd.h"
+
+static int page_size;
+static char *page;
+static int uffd;
+static int poison_fault_seen;
+static volatile int sigbus_seen;
+static sigjmp_buf jmpbuf;
+
+static void sigbus_handler(int sig)
+{
+ if (sig == SIGBUS) {
+ sigbus_seen = 1;
+ siglongjmp(jmpbuf, 1);
+ }
+}
+
+static void set_pages(void)
+{
+ page_size = sysconf(_SC_PAGE_SIZE);
+ page = SAFE_MMAP(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+}
+
+static void cleanup(void)
+{
+ if (page) {
+ SAFE_MUNMAP(page, page_size);
+ page = NULL;
+ }
+}
+
+static void *handle_thread(void)
+{
+ static struct uffd_msg msg;
+ struct uffdio_poison uffdio_poison = {};
+ struct pollfd pollfd;
+ int nready;
+
+ pollfd.fd = uffd;
+ pollfd.events = POLLIN;
+ nready = poll(&pollfd, 1, -1);
+ if (nready == -1)
+ tst_brk(TBROK | TERRNO, "Error on poll");
+
+ SAFE_READ(1, uffd, &msg, sizeof(msg));
+
+ if (msg.event != UFFD_EVENT_PAGEFAULT)
+ tst_brk(TFAIL, "Received unexpected UFFD_EVENT %d", msg.event);
+
+ tst_atomic_store(1, &poison_fault_seen);
+
+ /* Poison the page that triggered the fault */
+ uffdio_poison.range.start = msg.arg.pagefault.address & ~(page_size - 1);
+ uffdio_poison.range.len = page_size;
+
+ SAFE_IOCTL(uffd, UFFDIO_POISON, &uffdio_poison);
+
+ close(uffd);
+ return NULL;
+}
+
+static void run(void)
+{
+ pthread_t thr;
+ struct uffdio_api uffdio_api = {};
+ struct uffdio_register uffdio_register;
+ struct sigaction sa = {};
+ volatile char dummy;
+
+ sa.sa_handler = sigbus_handler;
+ sigemptyset(&sa.sa_mask);
+ SAFE_SIGACTION(SIGBUS, &sa, NULL);
+
+ set_pages();
+
+ uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
+
+ uffdio_api.api = UFFD_API;
+ uffdio_api.features = UFFD_FEATURE_POISON;
+
+ SAFE_IOCTL(uffd, UFFDIO_API, &uffdio_api);
+
+ if (!(uffdio_api.features & UFFD_FEATURE_POISON))
+ tst_brk(TCONF, "UFFD_FEATURE_POISON not supported");
+
+ uffdio_register.range.start = (unsigned long) page;
+ uffdio_register.range.len = page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+
+ SAFE_IOCTL(uffd, UFFDIO_REGISTER, &uffdio_register);
+
+ SAFE_PTHREAD_CREATE(&thr, NULL, (void *) handle_thread, NULL);
+
+ /* Try to read from the page: should trigger fault, get poisoned, then SIGBUS */
+ if (sigsetjmp(jmpbuf, 1) == 0) {
+ dummy = page[0];
+ (void)dummy;
+ }
+
+ SAFE_PTHREAD_JOIN(thr, NULL);
+
+ int poisoned = tst_atomic_load(&poison_fault_seen);
+
+ if (poisoned && sigbus_seen)
+ tst_res(TPASS, "POISON successfully triggered SIGBUS");
+ else if (poison_fault_seen && !sigbus_seen)
+ tst_res(TFAIL, "POISON fault seen but no SIGBUS received");
+ else if (!poison_fault_seen && sigbus_seen)
+ tst_res(TFAIL, "SIGBUS received but no poison fault seen");
+ else
+ tst_res(TFAIL, "No poison fault or SIGBUS observed");
+}
+
+static struct tst_test test = {
+ .test_all = run,
+ .cleanup = cleanup,
+};
--
2.53.0
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-19 22:50 [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON Ricardo Branco
@ 2026-02-20 10:41 ` Cyril Hrubis
2026-02-20 15:32 ` Andrea Cervesato via ltp
1 sibling, 0 replies; 8+ messages in thread
From: Cyril Hrubis @ 2026-02-20 10:41 UTC (permalink / raw)
To: Ricardo Branco; +Cc: ltp
Hi!
> Signed-off-by: Ricardo Branco <rbranco@suse.de>
> ---
> configure.ac | 1 +
> include/lapi/userfaultfd.h | 13 ++
> .../kernel/syscalls/userfaultfd/.gitignore | 1 +
> .../kernel/syscalls/userfaultfd/Makefile | 1 +
> .../syscalls/userfaultfd/userfaultfd06.c | 137 ++++++++++++++++++
> 5 files changed, 153 insertions(+)
> create mode 100644 testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
>
> diff --git a/configure.ac b/configure.ac
> index 7fa614dcb..94bcbcc98 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -278,6 +278,7 @@ AC_CHECK_TYPES([struct sockaddr_vm],,,[
> ])
>
> AC_CHECK_TYPES([struct uffdio_move],,,[#include <linux/userfaultfd.h>])
> +AC_CHECK_TYPES([struct uffdio_poison],,,[#include <linux/userfaultfd.h>])
> AC_CHECK_TYPES([struct uffdio_writeprotect],,,[#include <linux/userfaultfd.h>])
>
> # Tools knobs
> diff --git a/include/lapi/userfaultfd.h b/include/lapi/userfaultfd.h
> index 0c9e34c84..aab3890b7 100644
> --- a/include/lapi/userfaultfd.h
> +++ b/include/lapi/userfaultfd.h
> @@ -233,6 +233,19 @@ struct uffdio_writeprotect {
> };
> #endif /* HAVE_STRUCT_UFFDIO_WRITEPROTECT */
>
> +#ifndef HAVE_STRUCT_UFFDIO_POISON
> +#define UFFD_FEATURE_POISON (1<<14)
> +#define _UFFDIO_POISON (0x08)
> +#define UFFDIO_POISON _IOWR(UFFDIO, _UFFDIO_POISON, \
> + struct uffdio_poison)
> +struct uffdio_poison {
> + struct uffdio_range range;
> +#define UFFDIO_POISON_MODE_DONTWAKE ((__u64)1<<0)
> + __u64 mode;
> + __s64 updated;
> +};
> +#endif /* HAVE_STRUCT_UFFDIO_POISON */
> +
> #define SAFE_USERFAULTFD(flags, retry) \
> safe_userfaultfd(__FILE__, __LINE__, (flags), (retry))
>
> diff --git a/testcases/kernel/syscalls/userfaultfd/.gitignore b/testcases/kernel/syscalls/userfaultfd/.gitignore
> index fb2ae243b..bc32fdf3b 100644
> --- a/testcases/kernel/syscalls/userfaultfd/.gitignore
> +++ b/testcases/kernel/syscalls/userfaultfd/.gitignore
> @@ -3,3 +3,4 @@
> /userfaultfd03
> /userfaultfd04
> /userfaultfd05
> +/userfaultfd06
> diff --git a/testcases/kernel/syscalls/userfaultfd/Makefile b/testcases/kernel/syscalls/userfaultfd/Makefile
> index 96650a65a..3252e47df 100644
> --- a/testcases/kernel/syscalls/userfaultfd/Makefile
> +++ b/testcases/kernel/syscalls/userfaultfd/Makefile
> @@ -16,3 +16,4 @@ userfaultfd02: CFLAGS += -pthread
> userfaultfd03: CFLAGS += -pthread
> userfaultfd04: CFLAGS += -pthread
> userfaultfd05: CFLAGS += -pthread
> +userfaultfd06: CFLAGS += -pthread
> diff --git a/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c b/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
> new file mode 100644
> index 000000000..1f132d4d5
> --- /dev/null
> +++ b/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
> @@ -0,0 +1,137 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2026 SUSE LLC
> + * Author: Ricardo Branco <rbranco@suse.com>
> + */
> +
> +/*\
> + * Force a pagefault event and handle it using :manpage:`userfaultfd(2)`
> + * from a different thread testing UFFDIO_POISON.
> + */
> +
> +#include "config.h"
> +#include <poll.h>
> +#include <setjmp.h>
> +#include <signal.h>
> +#include <unistd.h>
> +#include "tst_test.h"
> +#include "tst_safe_macros.h"
> +#include "tst_safe_pthread.h"
> +#include "lapi/userfaultfd.h"
> +
> +static int page_size;
> +static char *page;
> +static int uffd;
> +static int poison_fault_seen;
> +static volatile int sigbus_seen;
> +static sigjmp_buf jmpbuf;
> +
> +static void sigbus_handler(int sig)
> +{
> + if (sig == SIGBUS) {
> + sigbus_seen = 1;
> + siglongjmp(jmpbuf, 1);
> + }
> +}
> +
> +static void set_pages(void)
> +{
> + page_size = sysconf(_SC_PAGE_SIZE);
> + page = SAFE_MMAP(NULL, page_size, PROT_READ | PROT_WRITE,
> + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
> +}
> +
> +static void cleanup(void)
> +{
> + if (page) {
> + SAFE_MUNMAP(page, page_size);
> + page = NULL;
> + }
> +}
> +
> +static void *handle_thread(void)
> +{
> + static struct uffd_msg msg;
> + struct uffdio_poison uffdio_poison = {};
> + struct pollfd pollfd;
> + int nready;
> +
> + pollfd.fd = uffd;
> + pollfd.events = POLLIN;
> + nready = poll(&pollfd, 1, -1);
> + if (nready == -1)
> + tst_brk(TBROK | TERRNO, "Error on poll");
> +
> + SAFE_READ(1, uffd, &msg, sizeof(msg));
> +
> + if (msg.event != UFFD_EVENT_PAGEFAULT)
> + tst_brk(TFAIL, "Received unexpected UFFD_EVENT %d", msg.event);
> +
> + tst_atomic_store(1, &poison_fault_seen);
> +
> + /* Poison the page that triggered the fault */
> + uffdio_poison.range.start = msg.arg.pagefault.address & ~(page_size - 1);
> + uffdio_poison.range.len = page_size;
> +
> + SAFE_IOCTL(uffd, UFFDIO_POISON, &uffdio_poison);
> +
> + close(uffd);
> + return NULL;
> +}
> +
> +static void run(void)
> +{
> + pthread_t thr;
> + struct uffdio_api uffdio_api = {};
> + struct uffdio_register uffdio_register;
> + struct sigaction sa = {};
> + volatile char dummy;
> +
> + sa.sa_handler = sigbus_handler;
> + sigemptyset(&sa.sa_mask);
> + SAFE_SIGACTION(SIGBUS, &sa, NULL);
The signal handle can be set once from the test setup().
And we have to reset the poison_fault_seen and sigbus_seen flags here so
that we actually test something with -i 2
> + set_pages();
> +
> + uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
> +
> + uffdio_api.api = UFFD_API;
> + uffdio_api.features = UFFD_FEATURE_POISON;
> +
> + SAFE_IOCTL(uffd, UFFDIO_API, &uffdio_api);
> +
> + if (!(uffdio_api.features & UFFD_FEATURE_POISON))
> + tst_brk(TCONF, "UFFD_FEATURE_POISON not supported");
> +
> + uffdio_register.range.start = (unsigned long) page;
> + uffdio_register.range.len = page_size;
> + uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
> +
> + SAFE_IOCTL(uffd, UFFDIO_REGISTER, &uffdio_register);
> +
> + SAFE_PTHREAD_CREATE(&thr, NULL, (void *) handle_thread, NULL);
> +
> + /* Try to read from the page: should trigger fault, get poisoned, then SIGBUS */
> + if (sigsetjmp(jmpbuf, 1) == 0) {
> + dummy = page[0];
> + (void)dummy;
Does LTP_VAR_USED(dummy) = page[0] work here instead of the volatile and
cast to the (void) ?
> + }
> +
> + SAFE_PTHREAD_JOIN(thr, NULL);
> +
> + int poisoned = tst_atomic_load(&poison_fault_seen);
> +
> + if (poisoned && sigbus_seen)
> + tst_res(TPASS, "POISON successfully triggered SIGBUS");
> + else if (poison_fault_seen && !sigbus_seen)
> + tst_res(TFAIL, "POISON fault seen but no SIGBUS received");
> + else if (!poison_fault_seen && sigbus_seen)
> + tst_res(TFAIL, "SIGBUS received but no poison fault seen");
> + else
> + tst_res(TFAIL, "No poison fault or SIGBUS observed");
> +}
> +
> +static struct tst_test test = {
> + .test_all = run,
> + .cleanup = cleanup,
> +};
> --
> 2.53.0
>
>
> --
> Mailing list info: https://lists.linux.it/listinfo/ltp
--
Cyril Hrubis
chrubis@suse.cz
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-19 22:50 [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON Ricardo Branco
2026-02-20 10:41 ` Cyril Hrubis
@ 2026-02-20 15:32 ` Andrea Cervesato via ltp
2026-02-20 15:43 ` Ricardo Branco
1 sibling, 1 reply; 8+ messages in thread
From: Andrea Cervesato via ltp @ 2026-02-20 15:32 UTC (permalink / raw)
To: Ricardo Branco, ltp
Hi!
On Thu Feb 19, 2026 at 11:50 PM CET, Ricardo Branco wrote:
> Signed-off-by: Ricardo Branco <rbranco@suse.de>
> ---
> configure.ac | 1 +
> include/lapi/userfaultfd.h | 13 ++
> .../kernel/syscalls/userfaultfd/.gitignore | 1 +
> .../kernel/syscalls/userfaultfd/Makefile | 1 +
> .../syscalls/userfaultfd/userfaultfd06.c | 137 ++++++++++++++++++
> 5 files changed, 153 insertions(+)
> create mode 100644 testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
>
> diff --git a/configure.ac b/configure.ac
> index 7fa614dcb..94bcbcc98 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -278,6 +278,7 @@ AC_CHECK_TYPES([struct sockaddr_vm],,,[
> ])
>
> AC_CHECK_TYPES([struct uffdio_move],,,[#include <linux/userfaultfd.h>])
> +AC_CHECK_TYPES([struct uffdio_poison],,,[#include <linux/userfaultfd.h>])
> AC_CHECK_TYPES([struct uffdio_writeprotect],,,[#include <linux/userfaultfd.h>])
>
> # Tools knobs
> diff --git a/include/lapi/userfaultfd.h b/include/lapi/userfaultfd.h
> index 0c9e34c84..aab3890b7 100644
> --- a/include/lapi/userfaultfd.h
> +++ b/include/lapi/userfaultfd.h
> @@ -233,6 +233,19 @@ struct uffdio_writeprotect {
> };
> #endif /* HAVE_STRUCT_UFFDIO_WRITEPROTECT */
>
> +#ifndef HAVE_STRUCT_UFFDIO_POISON
> +#define UFFD_FEATURE_POISON (1<<14)
> +#define _UFFDIO_POISON (0x08)
> +#define UFFDIO_POISON _IOWR(UFFDIO, _UFFDIO_POISON, \
> + struct uffdio_poison)
> +struct uffdio_poison {
> + struct uffdio_range range;
> +#define UFFDIO_POISON_MODE_DONTWAKE ((__u64)1<<0)
> + __u64 mode;
> + __s64 updated;
> +};
> +#endif /* HAVE_STRUCT_UFFDIO_POISON */
> +
> #define SAFE_USERFAULTFD(flags, retry) \
> safe_userfaultfd(__FILE__, __LINE__, (flags), (retry))
>
> diff --git a/testcases/kernel/syscalls/userfaultfd/.gitignore b/testcases/kernel/syscalls/userfaultfd/.gitignore
> index fb2ae243b..bc32fdf3b 100644
> --- a/testcases/kernel/syscalls/userfaultfd/.gitignore
> +++ b/testcases/kernel/syscalls/userfaultfd/.gitignore
> @@ -3,3 +3,4 @@
> /userfaultfd03
> /userfaultfd04
> /userfaultfd05
> +/userfaultfd06
> diff --git a/testcases/kernel/syscalls/userfaultfd/Makefile b/testcases/kernel/syscalls/userfaultfd/Makefile
> index 96650a65a..3252e47df 100644
> --- a/testcases/kernel/syscalls/userfaultfd/Makefile
> +++ b/testcases/kernel/syscalls/userfaultfd/Makefile
> @@ -16,3 +16,4 @@ userfaultfd02: CFLAGS += -pthread
> userfaultfd03: CFLAGS += -pthread
> userfaultfd04: CFLAGS += -pthread
> userfaultfd05: CFLAGS += -pthread
> +userfaultfd06: CFLAGS += -pthread
> diff --git a/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c b/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
> new file mode 100644
> index 000000000..1f132d4d5
> --- /dev/null
> +++ b/testcases/kernel/syscalls/userfaultfd/userfaultfd06.c
> @@ -0,0 +1,137 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2026 SUSE LLC
> + * Author: Ricardo Branco <rbranco@suse.com>
> + */
> +
> +/*\
> + * Force a pagefault event and handle it using :manpage:`userfaultfd(2)`
> + * from a different thread testing UFFDIO_POISON.
> + */
> +
> +#include "config.h"
> +#include <poll.h>
> +#include <setjmp.h>
> +#include <signal.h>
> +#include <unistd.h>
> +#include "tst_test.h"
> +#include "tst_safe_macros.h"
> +#include "tst_safe_pthread.h"
> +#include "lapi/userfaultfd.h"
> +
> +static int page_size;
> +static char *page;
> +static int uffd;
> +static int poison_fault_seen;
> +static volatile int sigbus_seen;
> +static sigjmp_buf jmpbuf;
> +
> +static void sigbus_handler(int sig)
> +{
> + if (sig == SIGBUS) {
> + sigbus_seen = 1;
> + siglongjmp(jmpbuf, 1);
> + }
> +}
> +
> +static void set_pages(void)
> +{
> + page_size = sysconf(_SC_PAGE_SIZE);
> + page = SAFE_MMAP(NULL, page_size, PROT_READ | PROT_WRITE,
> + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
> +}
> +
> +static void cleanup(void)
> +{
> + if (page) {
> + SAFE_MUNMAP(page, page_size);
> + page = NULL;
> + }
> +}
> +
> +static void *handle_thread(void)
> +{
> + static struct uffd_msg msg;
> + struct uffdio_poison uffdio_poison = {};
> + struct pollfd pollfd;
> + int nready;
> +
> + pollfd.fd = uffd;
> + pollfd.events = POLLIN;
> + nready = poll(&pollfd, 1, -1);
> + if (nready == -1)
> + tst_brk(TBROK | TERRNO, "Error on poll");
> +
> + SAFE_READ(1, uffd, &msg, sizeof(msg));
> +
> + if (msg.event != UFFD_EVENT_PAGEFAULT)
> + tst_brk(TFAIL, "Received unexpected UFFD_EVENT %d", msg.event);
> +
> + tst_atomic_store(1, &poison_fault_seen);
> +
> + /* Poison the page that triggered the fault */
> + uffdio_poison.range.start = msg.arg.pagefault.address & ~(page_size - 1);
> + uffdio_poison.range.len = page_size;
> +
> + SAFE_IOCTL(uffd, UFFDIO_POISON, &uffdio_poison);
> +
> + close(uffd);
> + return NULL;
> +}
> +
> +static void run(void)
> +{
> + pthread_t thr;
> + struct uffdio_api uffdio_api = {};
> + struct uffdio_register uffdio_register;
> + struct sigaction sa = {};
> + volatile char dummy;
Here you need to reset the variables for -i > 1
> +
> + sa.sa_handler = sigbus_handler;
> + sigemptyset(&sa.sa_mask);
> + SAFE_SIGACTION(SIGBUS, &sa, NULL);
> +
> + set_pages();
This is done every cycle of -i > 1, but memory is never released and
done once in cleanup().
> +
> + uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
Maybe this one should be closed inside run(), or even remove it from
static variables and passed to the thread, so we keep it inside run().
> +
> + uffdio_api.api = UFFD_API;
> + uffdio_api.features = UFFD_FEATURE_POISON;
> +
> + SAFE_IOCTL(uffd, UFFDIO_API, &uffdio_api);
> +
> + if (!(uffdio_api.features & UFFD_FEATURE_POISON))
> + tst_brk(TCONF, "UFFD_FEATURE_POISON not supported");
> +
> + uffdio_register.range.start = (unsigned long) page;
> + uffdio_register.range.len = page_size;
> + uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
> +
> + SAFE_IOCTL(uffd, UFFDIO_REGISTER, &uffdio_register);
> +
> + SAFE_PTHREAD_CREATE(&thr, NULL, (void *) handle_thread, NULL);
> +
> + /* Try to read from the page: should trigger fault, get poisoned, then SIGBUS */
> + if (sigsetjmp(jmpbuf, 1) == 0) {
> + dummy = page[0];
> + (void)dummy;
> + }
> +
> + SAFE_PTHREAD_JOIN(thr, NULL);
> +
> + int poisoned = tst_atomic_load(&poison_fault_seen);
> +
> + if (poisoned && sigbus_seen)
> + tst_res(TPASS, "POISON successfully triggered SIGBUS");
> + else if (poison_fault_seen && !sigbus_seen)
> + tst_res(TFAIL, "POISON fault seen but no SIGBUS received");
> + else if (!poison_fault_seen && sigbus_seen)
> + tst_res(TFAIL, "SIGBUS received but no poison fault seen");
> + else
> + tst_res(TFAIL, "No poison fault or SIGBUS observed");
> +}
> +
> +static struct tst_test test = {
> + .test_all = run,
> + .cleanup = cleanup,
> +};
You ar missing the runtest entry.
--
Andrea Cervesato
SUSE QE Automation Engineer Linux
andrea.cervesato@suse.com
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-20 15:32 ` Andrea Cervesato via ltp
@ 2026-02-20 15:43 ` Ricardo Branco
2026-02-20 15:47 ` Andrea Cervesato via ltp
2026-02-23 10:59 ` Cyril Hrubis
0 siblings, 2 replies; 8+ messages in thread
From: Ricardo Branco @ 2026-02-20 15:43 UTC (permalink / raw)
To: Andrea Cervesato, ltp
On 2/20/26 4:32 PM, Andrea Cervesato wrote:
>> +
>> + sa.sa_handler = sigbus_handler;
>> + sigemptyset(&sa.sa_mask);
>> + SAFE_SIGACTION(SIGBUS, &sa, NULL);
>> +
>> + set_pages();
> This is done every cycle of -i > 1, but memory is never released and
> done once in cleanup().
I'm moving sigaction to setup but set_pages() is called in run() on the
rest of the tests.
>> +
>> + uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
> Maybe this one should be closed inside run(), or even remove it from
> static variables and passed to the thread, so we keep it inside run().
But then we'd also have to fix the other tests.
>> +
>> +static struct tst_test test = {
>> + .test_all = run,
>> + .cleanup = cleanup,
>> +};
> You ar missing the runtest entry.
There's no runtest function. For now I'm using the other tests as template.
Best,
R
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-20 15:43 ` Ricardo Branco
@ 2026-02-20 15:47 ` Andrea Cervesato via ltp
2026-02-20 16:45 ` Ricardo Branco
2026-02-23 10:59 ` Cyril Hrubis
1 sibling, 1 reply; 8+ messages in thread
From: Andrea Cervesato via ltp @ 2026-02-20 15:47 UTC (permalink / raw)
To: Ricardo Branco, ltp
On Fri Feb 20, 2026 at 4:43 PM CET, Ricardo Branco wrote:
>
>
> On 2/20/26 4:32 PM, Andrea Cervesato wrote:
> >> +
> >> + sa.sa_handler = sigbus_handler;
> >> + sigemptyset(&sa.sa_mask);
> >> + SAFE_SIGACTION(SIGBUS, &sa, NULL);
> >> +
> >> + set_pages();
> > This is done every cycle of -i > 1, but memory is never released and
> > done once in cleanup().
> I'm moving sigaction to setup but set_pages() is called in run() on the
> rest of the tests.
But all other tests also have a reset_pages() at the end of run()
>
> >> +
> >> + uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
> > Maybe this one should be closed inside run(), or even remove it from
> > static variables and passed to the thread, so we keep it inside run().
>
> But then we'd also have to fix the other tests.
No problem, feel free to leave it then, i didn't see the big picture.
> >> +
> >> +static struct tst_test test = {
> >> + .test_all = run,
> >> + .cleanup = cleanup,
> >> +};
> > You ar missing the runtest entry.
>
> There's no runtest function. For now I'm using the other tests as template.
>
> Best,
> R
--
Andrea Cervesato
SUSE QE Automation Engineer Linux
andrea.cervesato@suse.com
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-20 15:47 ` Andrea Cervesato via ltp
@ 2026-02-20 16:45 ` Ricardo Branco
0 siblings, 0 replies; 8+ messages in thread
From: Ricardo Branco @ 2026-02-20 16:45 UTC (permalink / raw)
To: Andrea Cervesato, ltp
On 2/20/26 4:47 PM, Andrea Cervesato wrote:
> On Fri Feb 20, 2026 at 4:43 PM CET, Ricardo Branco wrote:
>>
>> On 2/20/26 4:32 PM, Andrea Cervesato wrote:
>>>> +
>>>> + sa.sa_handler = sigbus_handler;
>>>> + sigemptyset(&sa.sa_mask);
>>>> + SAFE_SIGACTION(SIGBUS, &sa, NULL);
>>>> +
>>>> + set_pages();
>>> This is done every cycle of -i > 1, but memory is never released and
>>> done once in cleanup().
>> I'm moving sigaction to setup but set_pages() is called in run() on the
>> rest of the tests.
> But all other tests also have a reset_pages() at the end of run()
Because I renamed reset_pages() to cleanup().
Will follow the template of the other tests in the next v5.
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-20 15:43 ` Ricardo Branco
2026-02-20 15:47 ` Andrea Cervesato via ltp
@ 2026-02-23 10:59 ` Cyril Hrubis
2026-02-23 13:16 ` Ricardo Branco
1 sibling, 1 reply; 8+ messages in thread
From: Cyril Hrubis @ 2026-02-23 10:59 UTC (permalink / raw)
To: Ricardo Branco; +Cc: ltp
Hi!
> >> + uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
> > Maybe this one should be closed inside run(), or even remove it from
> > static variables and passed to the thread, so we keep it inside run().
>
> But then we'd also have to fix the other tests.
> >> +
> >> +static struct tst_test test = {
> >> + .test_all = run,
> >> + .cleanup = cleanup,
> >> +};
> > You ar missing the runtest entry.
>
> There's no runtest function. For now I'm using the other tests as template.
Runtest entry in runtest/syscalls
--
Cyril Hrubis
chrubis@suse.cz
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON
2026-02-23 10:59 ` Cyril Hrubis
@ 2026-02-23 13:16 ` Ricardo Branco
0 siblings, 0 replies; 8+ messages in thread
From: Ricardo Branco @ 2026-02-23 13:16 UTC (permalink / raw)
To: Cyril Hrubis; +Cc: ltp
On 2/23/26 11:59 AM, Cyril Hrubis wrote:
> Hi!
>>>> + uffd = SAFE_USERFAULTFD(O_CLOEXEC | O_NONBLOCK, false);
>>> Maybe this one should be closed inside run(), or even remove it from
>>> static variables and passed to the thread, so we keep it inside run().
>> But then we'd also have to fix the other tests.
>>>> +
>>>> +static struct tst_test test = {
>>>> + .test_all = run,
>>>> + .cleanup = cleanup,
>>>> +};
>>> You ar missing the runtest entry.
>> There's no runtest function. For now I'm using the other tests as template.
> Runtest entry in runtest/syscalls
>
Arghhh. Sorry. Fixed in v6.
--
Mailing list info: https://lists.linux.it/listinfo/ltp
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2026-02-23 13:16 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-02-19 22:50 [LTP] [PATCH v4] userfaultfd: Add test using UFFDIO_POISON Ricardo Branco
2026-02-20 10:41 ` Cyril Hrubis
2026-02-20 15:32 ` Andrea Cervesato via ltp
2026-02-20 15:43 ` Ricardo Branco
2026-02-20 15:47 ` Andrea Cervesato via ltp
2026-02-20 16:45 ` Ricardo Branco
2026-02-23 10:59 ` Cyril Hrubis
2026-02-23 13:16 ` Ricardo Branco
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