A handful of module relocations were missing, this patch includes the
remaining ones. I also wrote some test cases to ensure that module
loading works properly. Some relocations cannot be supported in the
kernel, these include the ones that rely on thread local storage and
dynamic linking.
ULEB128 handling is a bit special because SET and SUB relocations must
happen together, and SET must happen before SUB. A psABI proposal [1]
mandates that the first SET_ULEB128 that appears before a SUB_ULEB128
is the associated SET_ULEB128.
This can be tested by enabling KUNIT, RUNTIME_KERNEL_TESTING_MENU, and
RISCV_MODULE_LINKING_KUNIT.
[1] https://github.com/riscv-non-isa/riscv-elf-psabi-doc/pull/403
Signed-off-by: Charlie Jenkins <[email protected]>
---
Changes in v3:
- Add prototypes to test_module_linking_main as recommended by intel
zero day bot
- Improve efficiency of ULEB128 pair matching
- Link to v2: https://lore.kernel.org/r/[email protected]
Changes in v2:
- Added ULEB128 relocations
- Link to v1: https://lore.kernel.org/r/[email protected]
---
Charlie Jenkins (2):
riscv: Add remaining module relocations
riscv: Add tests for riscv module loading
arch/riscv/Kconfig.debug | 1 +
arch/riscv/include/uapi/asm/elf.h | 6 +-
arch/riscv/kernel/Makefile | 1 +
arch/riscv/kernel/module.c | 207 ++++++++++++++++++---
arch/riscv/kernel/tests/Kconfig.debug | 32 ++++
arch/riscv/kernel/tests/Makefile | 1 +
arch/riscv/kernel/tests/module_test/Makefile | 15 ++
.../tests/module_test/test_module_linking_main.c | 78 ++++++++
arch/riscv/kernel/tests/module_test/test_set16.S | 23 +++
arch/riscv/kernel/tests/module_test/test_set32.S | 20 ++
arch/riscv/kernel/tests/module_test/test_set6.S | 23 +++
arch/riscv/kernel/tests/module_test/test_set8.S | 23 +++
arch/riscv/kernel/tests/module_test/test_sub16.S | 22 +++
arch/riscv/kernel/tests/module_test/test_sub32.S | 22 +++
arch/riscv/kernel/tests/module_test/test_sub6.S | 22 +++
arch/riscv/kernel/tests/module_test/test_sub64.S | 27 +++
arch/riscv/kernel/tests/module_test/test_sub8.S | 22 +++
arch/riscv/kernel/tests/module_test/test_uleb128.S | 20 ++
18 files changed, 539 insertions(+), 26 deletions(-)
---
base-commit: 4d320c2d9a2b22f53523a1b012cda17a50220965
change-id: 20230908-module_relocations-f63ced651bd7
--
- Charlie
Add test cases for the two main groups of relocations added: SUB and
SET, along with uleb128 which is a bit different because SUB and SET are
required to happen together.
Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/Kconfig.debug | 1 +
arch/riscv/kernel/Makefile | 1 +
arch/riscv/kernel/tests/Kconfig.debug | 32 +++++++++
arch/riscv/kernel/tests/Makefile | 1 +
arch/riscv/kernel/tests/module_test/Makefile | 15 +++++
.../tests/module_test/test_module_linking_main.c | 78 ++++++++++++++++++++++
arch/riscv/kernel/tests/module_test/test_set16.S | 23 +++++++
arch/riscv/kernel/tests/module_test/test_set32.S | 20 ++++++
arch/riscv/kernel/tests/module_test/test_set6.S | 23 +++++++
arch/riscv/kernel/tests/module_test/test_set8.S | 23 +++++++
arch/riscv/kernel/tests/module_test/test_sub16.S | 22 ++++++
arch/riscv/kernel/tests/module_test/test_sub32.S | 22 ++++++
arch/riscv/kernel/tests/module_test/test_sub6.S | 22 ++++++
arch/riscv/kernel/tests/module_test/test_sub64.S | 27 ++++++++
arch/riscv/kernel/tests/module_test/test_sub8.S | 22 ++++++
arch/riscv/kernel/tests/module_test/test_uleb128.S | 20 ++++++
16 files changed, 352 insertions(+)
diff --git a/arch/riscv/Kconfig.debug b/arch/riscv/Kconfig.debug
index e69de29bb2d1..eafe17ebf710 100644
--- a/arch/riscv/Kconfig.debug
+++ b/arch/riscv/Kconfig.debug
@@ -0,0 +1 @@
+source "arch/riscv/kernel/tests/Kconfig.debug"
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index 95cf25d48405..bb99657252f4 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -57,6 +57,7 @@ obj-y += stacktrace.o
obj-y += cacheinfo.o
obj-y += patch.o
obj-y += probes/
+obj-y += tests/
obj-$(CONFIG_MMU) += vdso.o vdso/
obj-$(CONFIG_RISCV_M_MODE) += traps_misaligned.o
diff --git a/arch/riscv/kernel/tests/Kconfig.debug b/arch/riscv/kernel/tests/Kconfig.debug
new file mode 100644
index 000000000000..05ca55fb4645
--- /dev/null
+++ b/arch/riscv/kernel/tests/Kconfig.debug
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menu "arch/riscv/kernel Testing and Coverage"
+
+menuconfig RUNTIME_KERNEL_TESTING_MENU
+ bool "arch/riscv/kernel runtime Testing"
+ def_bool y
+ help
+ Enable riscv kernel runtime testing.
+
+if RUNTIME_KERNEL_TESTING_MENU
+
+config RISCV_MODULE_LINKING_KUNIT
+ bool "KUnit test riscv module linking at runtime" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ Enable this option to test riscv module linking at boot. This will
+ enable a module called "test_module_linking".
+
+ KUnit tests run during boot and output the results to the debug log
+ in TAP format (http://testanything.org/). Only useful for kernel devs
+ running the KUnit test harness, and not intended for inclusion into a
+ production build.
+
+ For more information on KUnit and unit tests in general please refer
+ to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+ If unsure, say N.
+
+endif # RUNTIME_TESTING_MENU
+
+endmenu # "arch/riscv/kernel runtime Testing"
diff --git a/arch/riscv/kernel/tests/Makefile b/arch/riscv/kernel/tests/Makefile
new file mode 100644
index 000000000000..7d6c76cffe20
--- /dev/null
+++ b/arch/riscv/kernel/tests/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_RISCV_MODULE_LINKING_KUNIT) += module_test/
diff --git a/arch/riscv/kernel/tests/module_test/Makefile b/arch/riscv/kernel/tests/module_test/Makefile
new file mode 100644
index 000000000000..cacd50cd1127
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/Makefile
@@ -0,0 +1,15 @@
+obj-m += test_module_linking.o
+
+test_sub := test_sub6.o test_sub8.o test_sub16.o test_sub32.o test_sub64.o
+
+test_set := test_set6.o test_set8.o test_set16.o test_set32.o
+
+test_uleb := test_uleb128.o
+
+test_module_linking-objs += $(test_sub)
+
+test_module_linking-objs += $(test_set)
+
+test_module_linking-objs += $(test_uleb)
+
+test_module_linking-objs += test_module_linking_main.o
diff --git a/arch/riscv/kernel/tests/module_test/test_module_linking_main.c b/arch/riscv/kernel/tests/module_test/test_module_linking_main.c
new file mode 100644
index 000000000000..dd1cfc03040e
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_module_linking_main.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <kunit/test.h>
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Test module linking");
+
+extern int test_set32(void);
+extern int test_set16(void);
+extern int test_set8(void);
+extern int test_set6(void);
+extern long test_sub64(void);
+extern int test_sub32(void);
+extern int test_sub16(void);
+extern int test_sub8(void);
+extern int test_sub6(void);
+extern int test_uleb(void);
+
+#define CHECK_EQ(lhs, rhs) KUNIT_ASSERT_EQ(test, lhs, rhs)
+
+void run_test_set(struct kunit *test);
+void run_test_sub(struct kunit *test);
+void run_test_uleb(struct kunit *test);
+
+void run_test_set(struct kunit *test)
+{
+ int val32 = test_set32();
+ int val16 = test_set16();
+ int val8 = test_set8();
+ int val6 = test_set6();
+
+ CHECK_EQ(val32, 0);
+ CHECK_EQ(val16, 0);
+ CHECK_EQ(val8, 0);
+ CHECK_EQ(val6, 0);
+}
+
+void run_test_sub(struct kunit *test)
+{
+ int val64 = test_sub64();
+ int val32 = test_sub32();
+ int val16 = test_sub16();
+ int val8 = test_sub8();
+ int val6 = test_sub6();
+
+ CHECK_EQ(val64, 0);
+ CHECK_EQ(val32, 0);
+ CHECK_EQ(val16, 0);
+ CHECK_EQ(val8, 0);
+ CHECK_EQ(val6, 0);
+}
+
+void run_test_uleb(struct kunit *test)
+{
+ int valuleb = test_uleb();
+
+ CHECK_EQ(valuleb, 0);
+}
+
+static struct kunit_case __refdata riscv_module_linking_test_cases[] = {
+ KUNIT_CASE(run_test_set),
+ KUNIT_CASE(run_test_sub),
+ KUNIT_CASE(run_test_uleb),
+ {}
+};
+
+static struct kunit_suite riscv_module_linking_test_suite = {
+ .name = "riscv_checksum",
+ .test_cases = riscv_module_linking_test_cases,
+};
+
+kunit_test_suites(&riscv_module_linking_test_suite);
diff --git a/arch/riscv/kernel/tests/module_test/test_set16.S b/arch/riscv/kernel/tests/module_test/test_set16.S
new file mode 100644
index 000000000000..2be0e441a12e
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_set16.S
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_set16
+test_set16:
+ lw a0, set16
+ la t0, set16
+#ifdef CONFIG_32BIT
+ slli t0, t0, 16
+ srli t0, t0, 16
+#else
+ slli t0, t0, 48
+ srli t0, t0, 48
+#endif
+ sub a0, a0, t0
+ ret
+.data
+set16:
+ .reloc set16, R_RISCV_SET16, set16
+ .word 0
diff --git a/arch/riscv/kernel/tests/module_test/test_set32.S b/arch/riscv/kernel/tests/module_test/test_set32.S
new file mode 100644
index 000000000000..de0444537e67
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_set32.S
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_set32
+test_set32:
+ lw a0, set32
+ la t0, set32
+#ifndef CONFIG_32BIT
+ slli t0, t0, 32
+ srli t0, t0, 32
+#endif
+ sub a0, a0, t0
+ ret
+.data
+set32:
+ .reloc set32, R_RISCV_SET32, set32
+ .word 0
diff --git a/arch/riscv/kernel/tests/module_test/test_set6.S b/arch/riscv/kernel/tests/module_test/test_set6.S
new file mode 100644
index 000000000000..c39ce4c219eb
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_set6.S
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_set6
+test_set6:
+ lw a0, set6
+ la t0, set6
+#ifdef CONFIG_32BIT
+ slli t0, t0, 26
+ srli t0, t0, 26
+#else
+ slli t0, t0, 58
+ srli t0, t0, 58
+#endif
+ sub a0, a0, t0
+ ret
+.data
+set6:
+ .reloc set6, R_RISCV_SET6, set6
+ .word 0
diff --git a/arch/riscv/kernel/tests/module_test/test_set8.S b/arch/riscv/kernel/tests/module_test/test_set8.S
new file mode 100644
index 000000000000..a656173f6f99
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_set8.S
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_set8
+test_set8:
+ lw a0, set8
+ la t0, set8
+#ifdef CONFIG_32BIT
+ slli t0, t0, 24
+ srli t0, t0, 24
+#else
+ slli t0, t0, 56
+ srli t0, t0, 56
+#endif
+ sub a0, a0, t0
+ ret
+.data
+set8:
+ .reloc set8, R_RISCV_SET8, set8
+ .word 0
diff --git a/arch/riscv/kernel/tests/module_test/test_sub16.S b/arch/riscv/kernel/tests/module_test/test_sub16.S
new file mode 100644
index 000000000000..c561e155d1db
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub16.S
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_sub16
+test_sub16:
+ lh a0, sub16
+ addi a0, a0, -32
+ ret
+first:
+ .rept 8
+ .word 0
+ .endr
+second:
+
+.data
+sub16:
+ .reloc sub16, R_RISCV_ADD16, second
+ .reloc sub16, R_RISCV_SUB16, first
+ .half 0
diff --git a/arch/riscv/kernel/tests/module_test/test_sub32.S b/arch/riscv/kernel/tests/module_test/test_sub32.S
new file mode 100644
index 000000000000..93232c70cae6
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub32.S
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_sub32
+test_sub32:
+ lw a0, sub32
+ addi a0, a0, -32
+ ret
+first:
+ .rept 8
+ .word 0
+ .endr
+second:
+
+.data
+sub32:
+ .reloc sub32, R_RISCV_ADD32, second
+ .reloc sub32, R_RISCV_SUB32, first
+ .word 0
diff --git a/arch/riscv/kernel/tests/module_test/test_sub6.S b/arch/riscv/kernel/tests/module_test/test_sub6.S
new file mode 100644
index 000000000000..d9c9526ceb62
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub6.S
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_sub6
+test_sub6:
+ lb a0, sub6
+ addi a0, a0, -32
+ ret
+first:
+ .rept 8
+ .word 0
+ .endr
+second:
+
+.data
+sub6:
+ .reloc sub6, R_RISCV_SET6, second
+ .reloc sub6, R_RISCV_SUB6, first
+ .byte 0
diff --git a/arch/riscv/kernel/tests/module_test/test_sub64.S b/arch/riscv/kernel/tests/module_test/test_sub64.S
new file mode 100644
index 000000000000..6d260e2a5d98
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub64.S
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_sub64
+test_sub64:
+#ifdef CONFIG_32BIT
+ lw a0, sub64
+#else
+ ld a0, sub64
+#endif
+ addi a0, a0, -32
+ ret
+first:
+ .rept 8
+ .word 0
+ .endr
+second:
+
+.data
+sub64:
+ .reloc sub64, R_RISCV_ADD64, second
+ .reloc sub64, R_RISCV_SUB64, first
+ .word 0
+ .word 0
diff --git a/arch/riscv/kernel/tests/module_test/test_sub8.S b/arch/riscv/kernel/tests/module_test/test_sub8.S
new file mode 100644
index 000000000000..af7849115d4d
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub8.S
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_sub8
+test_sub8:
+ lb a0, sub8
+ addi a0, a0, -32
+ ret
+first:
+ .rept 8
+ .word 0
+ .endr
+second:
+
+.data
+sub8:
+ .reloc sub8, R_RISCV_ADD8, second
+ .reloc sub8, R_RISCV_SUB8, first
+ .byte 0
diff --git a/arch/riscv/kernel/tests/module_test/test_uleb128.S b/arch/riscv/kernel/tests/module_test/test_uleb128.S
new file mode 100644
index 000000000000..db9f301092d0
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_uleb128.S
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_uleb
+test_uleb:
+ ld a0, second
+ addi a0, a0, -127
+ ret
+.data
+first:
+ .rept 127
+ .byte 0
+ .endr
+second:
+ .reloc second, R_RISCV_SET_ULEB128, second
+ .reloc second, R_RISCV_SUB_ULEB128, first
+ .dword 0
--
2.42.0