[PATCH v9 05/10] kselftest/arm64/mte: register mte signal handler with SA_EXPOSE_TAGBITS

Yeoreum Yun yeoreum.yun at arm.com
Wed Jun 18 01:45:08 PDT 2025


To test address tag[63:60] and memory tag[59:56] is preserved
when memory tag fault happen, Let mte_register_signal() to register
signal handler with SA_EXPOSE_TAGBITS.

Signed-off-by: Yeoreum Yun <yeoreum.yun at arm.com>
Reviewed-by: Mark Brown <broonie at kernel.org>
---
 tools/testing/selftests/arm64/mte/check_buffer_fill.c |  2 +-
 .../testing/selftests/arm64/mte/check_child_memory.c  |  4 ++--
 .../selftests/arm64/mte/check_hugetlb_options.c       |  4 ++--
 tools/testing/selftests/arm64/mte/check_ksm_options.c |  4 ++--
 .../testing/selftests/arm64/mte/check_mmap_options.c  |  4 ++--
 .../selftests/arm64/mte/check_tags_inclusion.c        |  2 +-
 tools/testing/selftests/arm64/mte/check_user_mem.c    |  2 +-
 tools/testing/selftests/arm64/mte/mte_common_util.c   | 11 ++++++++++-
 tools/testing/selftests/arm64/mte/mte_common_util.h   |  3 ++-
 9 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/tools/testing/selftests/arm64/mte/check_buffer_fill.c b/tools/testing/selftests/arm64/mte/check_buffer_fill.c
index 2ee7f114d7fa..5248b5265aa4 100644
--- a/tools/testing/selftests/arm64/mte/check_buffer_fill.c
+++ b/tools/testing/selftests/arm64/mte/check_buffer_fill.c
@@ -415,7 +415,7 @@ int main(int argc, char *argv[])
 		return err;
 
 	/* Register SIGSEGV handler */
-	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
 
 	/* Set test plan */
 	ksft_set_plan(20);
diff --git a/tools/testing/selftests/arm64/mte/check_child_memory.c b/tools/testing/selftests/arm64/mte/check_child_memory.c
index 7597fc632cad..b97ea3981c21 100644
--- a/tools/testing/selftests/arm64/mte/check_child_memory.c
+++ b/tools/testing/selftests/arm64/mte/check_child_memory.c
@@ -160,8 +160,8 @@ int main(int argc, char *argv[])
 		return err;
 
 	/* Register SIGSEGV handler */
-	mte_register_signal(SIGSEGV, mte_default_handler);
-	mte_register_signal(SIGBUS, mte_default_handler);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
+	mte_register_signal(SIGBUS, mte_default_handler, false);
 
 	/* Set test plan */
 	ksft_set_plan(12);
diff --git a/tools/testing/selftests/arm64/mte/check_hugetlb_options.c b/tools/testing/selftests/arm64/mte/check_hugetlb_options.c
index 3bfcd3848432..4e644a606394 100644
--- a/tools/testing/selftests/arm64/mte/check_hugetlb_options.c
+++ b/tools/testing/selftests/arm64/mte/check_hugetlb_options.c
@@ -235,8 +235,8 @@ int main(int argc, char *argv[])
 		return err;
 
 	/* Register signal handlers */
-	mte_register_signal(SIGBUS, mte_default_handler);
-	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGBUS, mte_default_handler, false);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
 
 	allocate_hugetlb();
 
diff --git a/tools/testing/selftests/arm64/mte/check_ksm_options.c b/tools/testing/selftests/arm64/mte/check_ksm_options.c
index 88c74bc46d4f..afea4e381862 100644
--- a/tools/testing/selftests/arm64/mte/check_ksm_options.c
+++ b/tools/testing/selftests/arm64/mte/check_ksm_options.c
@@ -141,8 +141,8 @@ int main(int argc, char *argv[])
 		return KSFT_FAIL;
 	}
 	/* Register signal handlers */
-	mte_register_signal(SIGBUS, mte_default_handler);
-	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGBUS, mte_default_handler, false);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
 
 	/* Set test plan */
 	ksft_set_plan(4);
diff --git a/tools/testing/selftests/arm64/mte/check_mmap_options.c b/tools/testing/selftests/arm64/mte/check_mmap_options.c
index 17694caaff53..b37bf481c9f9 100644
--- a/tools/testing/selftests/arm64/mte/check_mmap_options.c
+++ b/tools/testing/selftests/arm64/mte/check_mmap_options.c
@@ -201,8 +201,8 @@ int main(int argc, char *argv[])
 	sizes[item - 1] = page_size + 1;
 
 	/* Register signal handlers */
-	mte_register_signal(SIGBUS, mte_default_handler);
-	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGBUS, mte_default_handler, false);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
 
 	/* Set test plan */
 	ksft_set_plan(22);
diff --git a/tools/testing/selftests/arm64/mte/check_tags_inclusion.c b/tools/testing/selftests/arm64/mte/check_tags_inclusion.c
index a3d1e23fe02a..b96296ab9870 100644
--- a/tools/testing/selftests/arm64/mte/check_tags_inclusion.c
+++ b/tools/testing/selftests/arm64/mte/check_tags_inclusion.c
@@ -180,7 +180,7 @@ int main(int argc, char *argv[])
 		return err;
 
 	/* Register SIGSEGV handler */
-	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
 
 	/* Set test plan */
 	ksft_set_plan(4);
diff --git a/tools/testing/selftests/arm64/mte/check_user_mem.c b/tools/testing/selftests/arm64/mte/check_user_mem.c
index f4ae5f87a3b7..d1d14aaaba16 100644
--- a/tools/testing/selftests/arm64/mte/check_user_mem.c
+++ b/tools/testing/selftests/arm64/mte/check_user_mem.c
@@ -211,7 +211,7 @@ int main(int argc, char *argv[])
 		return err;
 
 	/* Register signal handlers */
-	mte_register_signal(SIGSEGV, mte_default_handler);
+	mte_register_signal(SIGSEGV, mte_default_handler, false);
 
 	/* Set test plan */
 	ksft_set_plan(64);
diff --git a/tools/testing/selftests/arm64/mte/mte_common_util.c b/tools/testing/selftests/arm64/mte/mte_common_util.c
index a1dc2fe5285b..83240b980f9c 100644
--- a/tools/testing/selftests/arm64/mte/mte_common_util.c
+++ b/tools/testing/selftests/arm64/mte/mte_common_util.c
@@ -19,6 +19,10 @@
 #include "mte_common_util.h"
 #include "mte_def.h"
 
+#ifndef SA_EXPOSE_TAGBITS
+#define SA_EXPOSE_TAGBITS 0x00000800
+#endif
+
 #define INIT_BUFFER_SIZE       256
 
 struct mte_fault_cxt cur_mte_cxt;
@@ -79,12 +83,17 @@ void mte_default_handler(int signum, siginfo_t *si, void *uc)
 	}
 }
 
-void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *))
+void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *),
+			 bool export_tags)
 {
 	struct sigaction sa;
 
 	sa.sa_sigaction = handler;
 	sa.sa_flags = SA_SIGINFO;
+
+	if (export_tags && signal == SIGSEGV)
+		sa.sa_flags |= SA_EXPOSE_TAGBITS;
+
 	sigemptyset(&sa.sa_mask);
 	sigaction(signal, &sa, NULL);
 }
diff --git a/tools/testing/selftests/arm64/mte/mte_common_util.h b/tools/testing/selftests/arm64/mte/mte_common_util.h
index a0017a303beb..6b109e84fa39 100644
--- a/tools/testing/selftests/arm64/mte/mte_common_util.h
+++ b/tools/testing/selftests/arm64/mte/mte_common_util.h
@@ -40,7 +40,8 @@ extern struct mte_fault_cxt cur_mte_cxt;
 
 /* MTE utility functions */
 void mte_default_handler(int signum, siginfo_t *si, void *uc);
-void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *));
+void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *),
+			 bool export_tags);
 void mte_wait_after_trig(void);
 void *mte_allocate_memory(size_t size, int mem_type, int mapping, bool tags);
 void *mte_allocate_memory_tag_range(size_t size, int mem_type, int mapping,
-- 
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}




More information about the linux-arm-kernel mailing list