From 8cbe0accc4a6ba7ed34812a1c7e1ba67e7f7b2a4 Mon Sep 17 00:00:00 2001
From: Emil Renner Berthing <kernel@esmil.dk>
Date: Wed, 1 Nov 2023 11:32:59 -0700
Subject: [PATCH 1/3] riscv: Avoid unaligned access when relocating modules
With the C-extension regular 32bit instructions are not
necessarily aligned on 4-byte boundaries. RISC-V instructions
are in fact an ordered list of 16bit little-endian
"parcels", so access the instruction as such.
This should also make the code work in case someone builds
a big-endian RISC-V machine.
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231101-module_relocations-v9-1-8dfa3483c400@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
arch/riscv/kernel/module.c | 157 +++++++++++++++++++------------------
1 file changed, 81 insertions(+), 76 deletions(-)
diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 7c651d55fcbd..8286d3bb04f4 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -27,68 +27,90 @@ static bool riscv_insn_valid_32bit_offset(ptrdiff_t val)
#endif
}
-static int apply_r_riscv_32_rela(struct module *me, u32 *location, Elf_Addr v)
+static int riscv_insn_rmw(void *location, u32 keep, u32 set)
+{
+ u16 *parcel = location;
+ u32 insn = (u32)le16_to_cpu(parcel[0]) | (u32)le16_to_cpu(parcel[1]) << 16;
+
+ insn &= keep;
+ insn |= set;
+
+ parcel[0] = cpu_to_le16(insn);
+ parcel[1] = cpu_to_le16(insn >> 16);
+ return 0;
+}
+
+static int riscv_insn_rvc_rmw(void *location, u16 keep, u16 set)
+{
+ u16 *parcel = location;
+ u16 insn = le16_to_cpu(*parcel);
+
+ insn &= keep;
+ insn |= set;
+
+ *parcel = cpu_to_le16(insn);
+ return 0;
+}
+
+static int apply_r_riscv_32_rela(struct module *me, void *location, Elf_Addr v)
{
if (v != (u32)v) {
pr_err("%s: value %016llx out of range for 32-bit field\n",
me->name, (long long)v);
return -EINVAL;
}
- *location = v;
+ *(u32 *)location = v;
return 0;
}
-static int apply_r_riscv_64_rela(struct module *me, u32 *location, Elf_Addr v)
+static int apply_r_riscv_64_rela(struct module *me, void *location, Elf_Addr v)
{
*(u64 *)location = v;
return 0;
}
-static int apply_r_riscv_branch_rela(struct module *me, u32 *location,
+static int apply_r_riscv_branch_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
+ ptrdiff_t offset = (void *)v - location;
u32 imm12 = (offset & 0x1000) << (31 - 12);
u32 imm11 = (offset & 0x800) >> (11 - 7);
u32 imm10_5 = (offset & 0x7e0) << (30 - 10);
u32 imm4_1 = (offset & 0x1e) << (11 - 4);
- *location = (*location & 0x1fff07f) | imm12 | imm11 | imm10_5 | imm4_1;
- return 0;
+ return riscv_insn_rmw(location, 0x1fff07f, imm12 | imm11 | imm10_5 | imm4_1);
}
-static int apply_r_riscv_jal_rela(struct module *me, u32 *location,
+static int apply_r_riscv_jal_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
+ ptrdiff_t offset = (void *)v - location;
u32 imm20 = (offset & 0x100000) << (31 - 20);
u32 imm19_12 = (offset & 0xff000);
u32 imm11 = (offset & 0x800) << (20 - 11);
u32 imm10_1 = (offset & 0x7fe) << (30 - 10);
- *location = (*location & 0xfff) | imm20 | imm19_12 | imm11 | imm10_1;
- return 0;
+ return riscv_insn_rmw(location, 0xfff, imm20 | imm19_12 | imm11 | imm10_1);
}
-static int apply_r_riscv_rvc_branch_rela(struct module *me, u32 *location,
+static int apply_r_riscv_rvc_branch_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
+ ptrdiff_t offset = (void *)v - location;
u16 imm8 = (offset & 0x100) << (12 - 8);
u16 imm7_6 = (offset & 0xc0) >> (6 - 5);
u16 imm5 = (offset & 0x20) >> (5 - 2);
u16 imm4_3 = (offset & 0x18) << (12 - 5);
u16 imm2_1 = (offset & 0x6) << (12 - 10);
- *(u16 *)location = (*(u16 *)location & 0xe383) |
- imm8 | imm7_6 | imm5 | imm4_3 | imm2_1;
- return 0;
+ return riscv_insn_rvc_rmw(location, 0xe383,
+ imm8 | imm7_6 | imm5 | imm4_3 | imm2_1);
}
-static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location,
+static int apply_r_riscv_rvc_jump_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
+ ptrdiff_t offset = (void *)v - location;
u16 imm11 = (offset & 0x800) << (12 - 11);
u16 imm10 = (offset & 0x400) >> (10 - 8);
u16 imm9_8 = (offset & 0x300) << (12 - 11);
@@ -98,16 +120,14 @@ static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location,
u16 imm4 = (offset & 0x10) << (12 - 5);
u16 imm3_1 = (offset & 0xe) << (12 - 10);
- *(u16 *)location = (*(u16 *)location & 0xe003) |
- imm11 | imm10 | imm9_8 | imm7 | imm6 | imm5 | imm4 | imm3_1;
- return 0;
+ return riscv_insn_rvc_rmw(location, 0xe003,
+ imm11 | imm10 | imm9_8 | imm7 | imm6 | imm5 | imm4 | imm3_1);
}
-static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location,
+static int apply_r_riscv_pcrel_hi20_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
- s32 hi20;
+ ptrdiff_t offset = (void *)v - location;
if (!riscv_insn_valid_32bit_offset(offset)) {
pr_err(
@@ -116,23 +136,20 @@ static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location,
return -EINVAL;
}
- hi20 = (offset + 0x800) & 0xfffff000;
- *location = (*location & 0xfff) | hi20;
- return 0;
+ return riscv_insn_rmw(location, 0xfff, (offset + 0x800) & 0xfffff000);
}
-static int apply_r_riscv_pcrel_lo12_i_rela(struct module *me, u32 *location,
+static int apply_r_riscv_pcrel_lo12_i_rela(struct module *me, void *location,
Elf_Addr v)
{
/*
* v is the lo12 value to fill. It is calculated before calling this
* handler.
*/
- *location = (*location & 0xfffff) | ((v & 0xfff) << 20);
- return 0;
+ return riscv_insn_rmw(location, 0xfffff, (v & 0xfff) << 20);
}
-static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, u32 *location,
+static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, void *location,
Elf_Addr v)
{
/*
@@ -142,15 +159,12 @@ static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, u32 *location,
u32 imm11_5 = (v & 0xfe0) << (31 - 11);
u32 imm4_0 = (v & 0x1f) << (11 - 4);
- *location = (*location & 0x1fff07f) | imm11_5 | imm4_0;
- return 0;
+ return riscv_insn_rmw(location, 0x1fff07f, imm11_5 | imm4_0);
}
-static int apply_r_riscv_hi20_rela(struct module *me, u32 *location,
+static int apply_r_riscv_hi20_rela(struct module *me, void *location,
Elf_Addr v)
{
- s32 hi20;
-
if (IS_ENABLED(CONFIG_CMODEL_MEDLOW)) {
pr_err(
"%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
@@ -158,22 +172,20 @@ static int apply_r_riscv_hi20_rela(struct module *me, u32 *location,
return -EINVAL;
}
- hi20 = ((s32)v + 0x800) & 0xfffff000;
- *location = (*location & 0xfff) | hi20;
- return 0;
+ return riscv_insn_rmw(location, 0xfff, ((s32)v + 0x800) & 0xfffff000);
}
-static int apply_r_riscv_lo12_i_rela(struct module *me, u32 *location,
+static int apply_r_riscv_lo12_i_rela(struct module *me, void *location,
Elf_Addr v)
{
/* Skip medlow checking because of filtering by HI20 already */
s32 hi20 = ((s32)v + 0x800) & 0xfffff000;
s32 lo12 = ((s32)v - hi20);
- *location = (*location & 0xfffff) | ((lo12 & 0xfff) << 20);
- return 0;
+
+ return riscv_insn_rmw(location, 0xfffff, (lo12 & 0xfff) << 20);
}
-static int apply_r_riscv_lo12_s_rela(struct module *me, u32 *location,
+static int apply_r_riscv_lo12_s_rela(struct module *me, void *location,
Elf_Addr v)
{
/* Skip medlow checking because of filtering by HI20 already */
@@ -181,20 +193,18 @@ static int apply_r_riscv_lo12_s_rela(struct module *me, u32 *location,
s32 lo12 = ((s32)v - hi20);
u32 imm11_5 = (lo12 & 0xfe0) << (31 - 11);
u32 imm4_0 = (lo12 & 0x1f) << (11 - 4);
- *location = (*location & 0x1fff07f) | imm11_5 | imm4_0;
- return 0;
+
+ return riscv_insn_rmw(location, 0x1fff07f, imm11_5 | imm4_0);
}
-static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location,
+static int apply_r_riscv_got_hi20_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
- s32 hi20;
+ ptrdiff_t offset = (void *)v - location;
/* Always emit the got entry */
if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) {
- offset = module_emit_got_entry(me, v);
- offset = (void *)offset - (void *)location;
+ offset = (void *)module_emit_got_entry(me, v) - location;
} else {
pr_err(
"%s: can not generate the GOT entry for symbol = %016llx from PC = %p\n",
@@ -202,22 +212,19 @@ static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location,
return -EINVAL;
}
- hi20 = (offset + 0x800) & 0xfffff000;
- *location = (*location & 0xfff) | hi20;
- return 0;
+ return riscv_insn_rmw(location, 0xfff, (offset + 0x800) & 0xfffff000);
}
-static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location,
+static int apply_r_riscv_call_plt_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
+ ptrdiff_t offset = (void *)v - location;
u32 hi20, lo12;
if (!riscv_insn_valid_32bit_offset(offset)) {
/* Only emit the plt entry if offset over 32-bit range */
if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) {
- offset = module_emit_plt_entry(me, v);
- offset = (void *)offset - (void *)location;
+ offset = (void *)module_emit_plt_entry(me, v) - location;
} else {
pr_err(
"%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
@@ -228,15 +235,14 @@ static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location,
hi20 = (offset + 0x800) & 0xfffff000;
lo12 = (offset - hi20) & 0xfff;
- *location = (*location & 0xfff) | hi20;
- *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20);
- return 0;
+ riscv_insn_rmw(location, 0xfff, hi20);
+ return riscv_insn_rmw(location + 4, 0xfffff, lo12 << 20);
}
-static int apply_r_riscv_call_rela(struct module *me, u32 *location,
+static int apply_r_riscv_call_rela(struct module *me, void *location,
Elf_Addr v)
{
- ptrdiff_t offset = (void *)v - (void *)location;
+ ptrdiff_t offset = (void *)v - location;
u32 hi20, lo12;
if (!riscv_insn_valid_32bit_offset(offset)) {
@@ -248,18 +254,17 @@ static int apply_r_riscv_call_rela(struct module *me, u32 *location,
hi20 = (offset + 0x800) & 0xfffff000;
lo12 = (offset - hi20) & 0xfff;
- *location = (*location & 0xfff) | hi20;
- *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20);
- return 0;
+ riscv_insn_rmw(location, 0xfff, hi20);
+ return riscv_insn_rmw(location + 4, 0xfffff, lo12 << 20);
}
-static int apply_r_riscv_relax_rela(struct module *me, u32 *location,
+static int apply_r_riscv_relax_rela(struct module *me, void *location,
Elf_Addr v)
{
return 0;
}
-static int apply_r_riscv_align_rela(struct module *me, u32 *location,
+static int apply_r_riscv_align_rela(struct module *me, void *location,
Elf_Addr v)
{
pr_err(
@@ -268,49 +273,49 @@ static int apply_r_riscv_align_rela(struct module *me, u32 *location,
return -EINVAL;
}
-static int apply_r_riscv_add16_rela(struct module *me, u32 *location,
+static int apply_r_riscv_add16_rela(struct module *me, void *location,
Elf_Addr v)
{
*(u16 *)location += (u16)v;
return 0;
}
-static int apply_r_riscv_add32_rela(struct module *me, u32 *location,
+static int apply_r_riscv_add32_rela(struct module *me, void *location,
Elf_Addr v)
{
*(u32 *)location += (u32)v;
return 0;
}
-static int apply_r_riscv_add64_rela(struct module *me, u32 *location,
+static int apply_r_riscv_add64_rela(struct module *me, void *location,
Elf_Addr v)
{
*(u64 *)location += (u64)v;
return 0;
}
-static int apply_r_riscv_sub16_rela(struct module *me, u32 *location,
+static int apply_r_riscv_sub16_rela(struct module *me, void *location,
Elf_Addr v)
{
*(u16 *)location -= (u16)v;
return 0;
}
-static int apply_r_riscv_sub32_rela(struct module *me, u32 *location,
+static int apply_r_riscv_sub32_rela(struct module *me, void *location,
Elf_Addr v)
{
*(u32 *)location -= (u32)v;
return 0;
}
-static int apply_r_riscv_sub64_rela(struct module *me, u32 *location,
+static int apply_r_riscv_sub64_rela(struct module *me, void *location,
Elf_Addr v)
{
*(u64 *)location -= (u64)v;
return 0;
}
-static int (*reloc_handlers_rela[]) (struct module *me, u32 *location,
+static int (*reloc_handlers_rela[]) (struct module *me, void *location,
Elf_Addr v) = {
[R_RISCV_32] = apply_r_riscv_32_rela,
[R_RISCV_64] = apply_r_riscv_64_rela,
@@ -342,9 +347,9 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
struct module *me)
{
Elf_Rela *rel = (void *) sechdrs[relsec].sh_addr;
- int (*handler)(struct module *me, u32 *location, Elf_Addr v);
+ int (*handler)(struct module *me, void *location, Elf_Addr v);
Elf_Sym *sym;
- u32 *location;
+ void *location;
unsigned int i, type;
Elf_Addr v;
int res;
From 8fd6c5142395a106b63c8668e9f4a7106b6a0772 Mon Sep 17 00:00:00 2001
From: Charlie Jenkins <charlie@rivosinc.com>
Date: Wed, 1 Nov 2023 11:33:00 -0700
Subject: [PATCH 2/3] riscv: Add remaining module relocations
Add all final module relocations and add error logs explaining the ones
that are not supported. Implement overflow checks for
ADD/SUB/SET/ULEB128 relocations.
Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231101-module_relocations-v9-2-8dfa3483c400@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
arch/riscv/include/uapi/asm/elf.h | 5 +-
arch/riscv/kernel/module.c | 448 ++++++++++++++++++++++++++++--
2 files changed, 423 insertions(+), 30 deletions(-)
diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h
index d696d6610231..11a71b8533d5 100644
--- a/arch/riscv/include/uapi/asm/elf.h
+++ b/arch/riscv/include/uapi/asm/elf.h
@@ -49,6 +49,7 @@ typedef union __riscv_fp_state elf_fpregset_t;
#define R_RISCV_TLS_DTPREL64 9
#define R_RISCV_TLS_TPREL32 10
#define R_RISCV_TLS_TPREL64 11
+#define R_RISCV_IRELATIVE 58
/* Relocation types not used by the dynamic linker */
#define R_RISCV_BRANCH 16
@@ -81,7 +82,6 @@ typedef union __riscv_fp_state elf_fpregset_t;
#define R_RISCV_ALIGN 43
#define R_RISCV_RVC_BRANCH 44
#define R_RISCV_RVC_JUMP 45
-#define R_RISCV_LUI 46
#define R_RISCV_GPREL_I 47
#define R_RISCV_GPREL_S 48
#define R_RISCV_TPREL_I 49
@@ -93,6 +93,9 @@ typedef union __riscv_fp_state elf_fpregset_t;
#define R_RISCV_SET16 55
#define R_RISCV_SET32 56
#define R_RISCV_32_PCREL 57
+#define R_RISCV_PLT32 59
+#define R_RISCV_SET_ULEB128 60
+#define R_RISCV_SUB_ULEB128 61
#endif /* _UAPI_ASM_RISCV_ELF_H */
diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c
index 8286d3bb04f4..4b339729d5ec 100644
--- a/arch/riscv/kernel/module.c
+++ b/arch/riscv/kernel/module.c
@@ -7,6 +7,9 @@
#include <linux/elf.h>
#include <linux/err.h>
#include <linux/errno.h>
+#include <linux/hashtable.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
#include <linux/moduleloader.h>
#include <linux/vmalloc.h>
#include <linux/sizes.h>
@@ -14,6 +17,38 @@
#include <asm/alternative.h>
#include <asm/sections.h>
+struct used_bucket {
+ struct list_head head;
+ struct hlist_head *bucket;
+};
+
+struct relocation_head {
+ struct hlist_node node;
+ struct list_head *rel_entry;
+ void *location;
+};
+
+struct relocation_entry {
+ struct list_head head;
+ Elf_Addr value;
+ unsigned int type;
+};
+
+struct relocation_handlers {
+ int (*reloc_handler)(struct module *me, void *location, Elf_Addr v);
+ int (*accumulate_handler)(struct module *me, void *location,
+ long buffer);
+};
+
+unsigned int initialize_relocation_hashtable(unsigned int num_relocations);
+void process_accumulated_relocations(struct module *me);
+int add_relocation_to_accumulate(struct module *me, int type, void *location,
+ unsigned int hashtable_bits, Elf_Addr v);
+
+struct hlist_head *relocation_hashtable;
+
+struct list_head used_buckets_list;
+
/*
* The auipc+jalr instruction pair can reach any PC-relative offset
* in the range [-2^31 - 2^11, 2^31 - 2^11)
@@ -273,6 +308,12 @@ static int apply_r_riscv_align_rela(struct module *me, void *location,
return -EINVAL;
}
+static int apply_r_riscv_add8_rela(struct module *me, void *location, Elf_Addr v)
+{
+ *(u8 *)location += (u8)v;
+ return 0;
+}
+
static int apply_r_riscv_add16_rela(struct module *me, void *location,
Elf_Addr v)
{
@@ -294,6 +335,12 @@ static int apply_r_riscv_add64_rela(struct module *me, void *location,
return 0;
}
+static int apply_r_riscv_sub8_rela(struct module *me, void *location, Elf_Addr v)
+{
+ *(u8 *)location -= (u8)v;
+ return 0;
+}
+
static int apply_r_riscv_sub16_rela(struct module *me, void *location,
Elf_Addr v)
{
@@ -315,33 +362,369 @@ static int apply_r_riscv_sub64_rela(struct module *me, void *location,
return 0;
}
-static int (*reloc_handlers_rela[]) (struct module *me, void *location,
- Elf_Addr v) = {
- [R_RISCV_32] = apply_r_riscv_32_rela,
- [R_RISCV_64] = apply_r_riscv_64_rela,
- [R_RISCV_BRANCH] = apply_r_riscv_branch_rela,
- [R_RISCV_JAL] = apply_r_riscv_jal_rela,
- [R_RISCV_RVC_BRANCH] = apply_r_riscv_rvc_branch_rela,
- [R_RISCV_RVC_JUMP] = apply_r_riscv_rvc_jump_rela,
- [R_RISCV_PCREL_HI20] = apply_r_riscv_pcrel_hi20_rela,
- [R_RISCV_PCREL_LO12_I] = apply_r_riscv_pcrel_lo12_i_rela,
- [R_RISCV_PCREL_LO12_S] = apply_r_riscv_pcrel_lo12_s_rela,
- [R_RISCV_HI20] = apply_r_riscv_hi20_rela,
- [R_RISCV_LO12_I] = apply_r_riscv_lo12_i_rela,
- [R_RISCV_LO12_S] = apply_r_riscv_lo12_s_rela,
- [R_RISCV_GOT_HI20] = apply_r_riscv_got_hi20_rela,
- [R_RISCV_CALL_PLT] = apply_r_riscv_call_plt_rela,
- [R_RISCV_CALL] = apply_r_riscv_call_rela,
- [R_RISCV_RELAX] = apply_r_riscv_relax_rela,
- [R_RISCV_ALIGN] = apply_r_riscv_align_rela,
- [R_RISCV_ADD16] = apply_r_riscv_add16_rela,
- [R_RISCV_ADD32] = apply_r_riscv_add32_rela,
- [R_RISCV_ADD64] = apply_r_riscv_add64_rela,
- [R_RISCV_SUB16] = apply_r_riscv_sub16_rela,
- [R_RISCV_SUB32] = apply_r_riscv_sub32_rela,
- [R_RISCV_SUB64] = apply_r_riscv_sub64_rela,
+static int dynamic_linking_not_supported(struct module *me, void *location,
+ Elf_Addr v)
+{
+ pr_err("%s: Dynamic linking not supported in kernel modules PC = %p\n",
+ me->name, location);
+ return -EINVAL;
+}
+
+static int tls_not_supported(struct module *me, void *location, Elf_Addr v)
+{
+ pr_err("%s: Thread local storage not supported in kernel modules PC = %p\n",
+ me->name, location);
+ return -EINVAL;
+}
+
+static int apply_r_riscv_sub6_rela(struct module *me, void *location, Elf_Addr v)
+{
+ u8 *byte = location;
+ u8 value = v;
+
+ *byte = (*byte - (value & 0x3f)) & 0x3f;
+ return 0;
+}
+
+static int apply_r_riscv_set6_rela(struct module *me, void *location, Elf_Addr v)
+{
+ u8 *byte = location;
+ u8 value = v;
+
+ *byte = (*byte & 0xc0) | (value & 0x3f);
+ return 0;
+}
+
+static int apply_r_riscv_set8_rela(struct module *me, void *location, Elf_Addr v)
+{
+ *(u8 *)location = (u8)v;
+ return 0;
+}
+
+static int apply_r_riscv_set16_rela(struct module *me, void *location,
+ Elf_Addr v)
+{
+ *(u16 *)location = (u16)v;
+ return 0;
+}
+
+static int apply_r_riscv_set32_rela(struct module *me, void *location,
+ Elf_Addr v)
+{
+ *(u32 *)location = (u32)v;
+ return 0;
+}
+
+static int apply_r_riscv_32_pcrel_rela(struct module *me, void *location,
+ Elf_Addr v)
+{
+ *(u32 *)location = v - (uintptr_t)location;
+ return 0;
+}
+
+static int apply_r_riscv_plt32_rela(struct module *me, void *location,
+ Elf_Addr v)
+{
+ ptrdiff_t offset = (void *)v - location;
+
+ if (!riscv_insn_valid_32bit_offset(offset)) {
+ /* Only emit the plt entry if offset over 32-bit range */
+ if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) {
+ offset = (void *)module_emit_plt_entry(me, v) - location;
+ } else {
+ pr_err("%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n",
+ me->name, (long long)v, location);
+ return -EINVAL;
+ }
+ }
+
+ *(u32 *)location = (u32)offset;
+ return 0;
+}
+
+static int apply_r_riscv_set_uleb128(struct module *me, void *location, Elf_Addr v)
+{
+ *(long *)location = v;
+ return 0;
+}
+
+static int apply_r_riscv_sub_uleb128(struct module *me, void *location, Elf_Addr v)
+{
+ *(long *)location -= v;
+ return 0;
+}
+
+static int apply_6_bit_accumulation(struct module *me, void *location, long buffer)
+{
+ u8 *byte = location;
+ u8 value = buffer;
+
+ if (buffer > 0x3f) {
+ pr_err("%s: value %ld out of range for 6-bit relocation.\n",
+ me->name, buffer);
+ return -EINVAL;
+ }
+
+ *byte = (*byte & 0xc0) | (value & 0x3f);
+ return 0;
+}
+
+static int apply_8_bit_accumulation(struct module *me, void *location, long buffer)
+{
+ if (buffer > U8_MAX) {
+ pr_err("%s: value %ld out of range for 8-bit relocation.\n",
+ me->name, buffer);
+ return -EINVAL;
+ }
+ *(u8 *)location = (u8)buffer;
+ return 0;
+}
+
+static int apply_16_bit_accumulation(struct module *me, void *location, long buffer)
+{
+ if (buffer > U16_MAX) {
+ pr_err("%s: value %ld out of range for 16-bit relocation.\n",
+ me->name, buffer);
+ return -EINVAL;
+ }
+ *(u16 *)location = (u16)buffer;
+ return 0;
+}
+
+static int apply_32_bit_accumulation(struct module *me, void *location, long buffer)
+{
+ if (buffer > U32_MAX) {
+ pr_err("%s: value %ld out of range for 32-bit relocation.\n",
+ me->name, buffer);
+ return -EINVAL;
+ }
+ *(u32 *)location = (u32)buffer;
+ return 0;
+}
+
+static int apply_64_bit_accumulation(struct module *me, void *location, long buffer)
+{
+ *(u64 *)location = (u64)buffer;
+ return 0;
+}
+
+static int apply_uleb128_accumulation(struct module *me, void *location, long buffer)
+{
+ /*
+ * ULEB128 is a variable length encoding. Encode the buffer into
+ * the ULEB128 data format.
+ */
+ u8 *p = location;
+
+ while (buffer != 0) {
+ u8 value = buffer & 0x7f;
+
+ buffer >>= 7;
+ value |= (!!buffer) << 7;
+
+ *p++ = value;
+ }
+ return 0;
+}
+
+/*
+ * Relocations defined in the riscv-elf-psabi-doc.
+ * This handles static linking only.
+ */
+static const struct relocation_handlers reloc_handlers[] = {
+ [R_RISCV_32] = { apply_r_riscv_32_rela },
+ [R_RISCV_64] = { apply_r_riscv_64_rela },
+ [R_RISCV_RELATIVE] = { dynamic_linking_not_supported },
+ [R_RISCV_COPY] = { dynamic_linking_not_supported },
+ [R_RISCV_JUMP_SLOT] = { dynamic_linking_not_supported },
+ [R_RISCV_TLS_DTPMOD32] = { dynamic_linking_not_supported },
+ [R_RISCV_TLS_DTPMOD64] = { dynamic_linking_not_supported },
+ [R_RISCV_TLS_DTPREL32] = { dynamic_linking_not_supported },
+ [R_RISCV_TLS_DTPREL64] = { dynamic_linking_not_supported },
+ [R_RISCV_TLS_TPREL32] = { dynamic_linking_not_supported },
+ [R_RISCV_TLS_TPREL64] = { dynamic_linking_not_supported },
+ /* 12-15 undefined */
+ [R_RISCV_BRANCH] = { apply_r_riscv_branch_rela },
+ [R_RISCV_JAL] = { apply_r_riscv_jal_rela },
+ [R_RISCV_CALL] = { apply_r_riscv_call_rela },
+ [R_RISCV_CALL_PLT] = { apply_r_riscv_call_plt_rela },
+ [R_RISCV_GOT_HI20] = { apply_r_riscv_got_hi20_rela },
+ [R_RISCV_TLS_GOT_HI20] = { tls_not_supported },
+ [R_RISCV_TLS_GD_HI20] = { tls_not_supported },
+ [R_RISCV_PCREL_HI20] = { apply_r_riscv_pcrel_hi20_rela },
+ [R_RISCV_PCREL_LO12_I] = { apply_r_riscv_pcrel_lo12_i_rela },
+ [R_RISCV_PCREL_LO12_S] = { apply_r_riscv_pcrel_lo12_s_rela },
+ [R_RISCV_HI20] = { apply_r_riscv_hi20_rela },
+ [R_RISCV_LO12_I] = { apply_r_riscv_lo12_i_rela },
+ [R_RISCV_LO12_S] = { apply_r_riscv_lo12_s_rela },
+ [R_RISCV_TPREL_HI20] = { tls_not_supported },
+ [R_RISCV_TPREL_LO12_I] = { tls_not_supported },
+ [R_RISCV_TPREL_LO12_S] = { tls_not_supported },
+ [R_RISCV_TPREL_ADD] = { tls_not_supported },
+ [R_RISCV_ADD8] = { apply_r_riscv_add8_rela, apply_8_bit_accumulation },
+ [R_RISCV_ADD16] = { apply_r_riscv_add16_rela,
+ apply_16_bit_accumulation },
+ [R_RISCV_ADD32] = { apply_r_riscv_add32_rela,
+ apply_32_bit_accumulation },
+ [R_RISCV_ADD64] = { apply_r_riscv_add64_rela,
+ apply_64_bit_accumulation },
+ [R_RISCV_SUB8] = { apply_r_riscv_sub8_rela, apply_8_bit_accumulation },
+ [R_RISCV_SUB16] = { apply_r_riscv_sub16_rela,
+ apply_16_bit_accumulation },
+ [R_RISCV_SUB32] = { apply_r_riscv_sub32_rela,
+ apply_32_bit_accumulation },
+ [R_RISCV_SUB64] = { apply_r_riscv_sub64_rela,
+ apply_64_bit_accumulation },
+ /* 41-42 reserved for future standard use */
+ [R_RISCV_ALIGN] = { apply_r_riscv_align_rela },
+ [R_RISCV_RVC_BRANCH] = { apply_r_riscv_rvc_branch_rela },
+ [R_RISCV_RVC_JUMP] = { apply_r_riscv_rvc_jump_rela },
+ /* 46-50 reserved for future standard use */
+ [R_RISCV_RELAX] = { apply_r_riscv_relax_rela },
+ [R_RISCV_SUB6] = { apply_r_riscv_sub6_rela, apply_6_bit_accumulation },
+ [R_RISCV_SET6] = { apply_r_riscv_set6_rela, apply_6_bit_accumulation },
+ [R_RISCV_SET8] = { apply_r_riscv_set8_rela, apply_8_bit_accumulation },
+ [R_RISCV_SET16] = { apply_r_riscv_set16_rela,
+ apply_16_bit_accumulation },
+ [R_RISCV_SET32] = { apply_r_riscv_set32_rela,
+ apply_32_bit_accumulation },
+ [R_RISCV_32_PCREL] = { apply_r_riscv_32_pcrel_rela },
+ [R_RISCV_IRELATIVE] = { dynamic_linking_not_supported },
+ [R_RISCV_PLT32] = { apply_r_riscv_plt32_rela },
+ [R_RISCV_SET_ULEB128] = { apply_r_riscv_set_uleb128,
+ apply_uleb128_accumulation },
+ [R_RISCV_SUB_ULEB128] = { apply_r_riscv_sub_uleb128,
+ apply_uleb128_accumulation },
+ /* 62-191 reserved for future standard use */
+ /* 192-255 nonstandard ABI extensions */
};
+void process_accumulated_relocations(struct module *me)
+{
+ /*
+ * Only ADD/SUB/SET/ULEB128 should end up here.
+ *
+ * Each bucket may have more than one relocation location. All
+ * relocations for a location are stored in a list in a bucket.
+ *
+ * Relocations are applied to a temp variable before being stored to the
+ * provided location to check for overflow. This also allows ULEB128 to
+ * properly decide how many entries are needed before storing to
+ * location. The final value is stored into location using the handler
+ * for the last relocation to an address.
+ *
+ * Three layers of indexing:
+ * - Each of the buckets in use
+ * - Groups of relocations in each bucket by location address
+ * - Each relocation entry for a location address
+ */
+ struct used_bucket *bucket_iter;
+ struct relocation_head *rel_head_iter;
+ struct relocation_entry *rel_entry_iter;
+ int curr_type;
+ void *location;
+ long buffer;
+
+ list_for_each_entry(bucket_iter, &used_buckets_list, head) {
+ hlist_for_each_entry(rel_head_iter, bucket_iter->bucket, node) {
+ buffer = 0;
+ location = rel_head_iter->location;
+ list_for_each_entry(rel_entry_iter,
+ rel_head_iter->rel_entry, head) {
+ curr_type = rel_entry_iter->type;
+ reloc_handlers[curr_type].reloc_handler(
+ me, &buffer, rel_entry_iter->value);
+ kfree(rel_entry_iter);
+ }
+ reloc_handlers[curr_type].accumulate_handler(
+ me, location, buffer);
+ kfree(rel_head_iter);
+ }
+ kfree(bucket_iter);
+ }
+
+ kfree(relocation_hashtable);
+}
+
+int add_relocation_to_accumulate(struct module *me, int type, void *location,
+ unsigned int hashtable_bits, Elf_Addr v)
+{
+ struct relocation_entry *entry;
+ struct relocation_head *rel_head;
+ struct hlist_head *current_head;
+ struct used_bucket *bucket;
+ unsigned long hash;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ INIT_LIST_HEAD(&entry->head);
+ entry->type = type;
+ entry->value = v;
+
+ hash = hash_min((uintptr_t)location, hashtable_bits);
+
+ current_head = &relocation_hashtable[hash];
+
+ /* Find matching location (if any) */
+ bool found = false;
+ struct relocation_head *rel_head_iter;
+
+ hlist_for_each_entry(rel_head_iter, current_head, node) {
+ if (rel_head_iter->location == location) {
+ found = true;
+ rel_head = rel_head_iter;
+ break;
+ }
+ }
+
+ if (!found) {
+ rel_head = kmalloc(sizeof(*rel_head), GFP_KERNEL);
+ rel_head->rel_entry =
+ kmalloc(sizeof(struct list_head), GFP_KERNEL);
+ INIT_LIST_HEAD(rel_head->rel_entry);
+ rel_head->location = location;
+ INIT_HLIST_NODE(&rel_head->node);
+ if (!current_head->first) {
+ bucket =
+ kmalloc(sizeof(struct used_bucket), GFP_KERNEL);
+ INIT_LIST_HEAD(&bucket->head);
+ bucket->bucket = current_head;
+ list_add(&bucket->head, &used_buckets_list);
+ }
+ hlist_add_head(&rel_head->node, current_head);
+ }
+
+ /* Add relocation to head of discovered rel_head */
+ list_add_tail(&entry->head, rel_head->rel_entry);
+
+ return 0;
+}
+
+unsigned int initialize_relocation_hashtable(unsigned int num_relocations)
+{
+ /* Can safely assume that bits is not greater than sizeof(long) */
+ unsigned long hashtable_size = roundup_pow_of_two(num_relocations);
+ unsigned int hashtable_bits = ilog2(hashtable_size);
+
+ /*
+ * Double size of hashtable if num_relocations * 1.25 is greater than
+ * hashtable_size.
+ */
+ int should_double_size = ((num_relocations + (num_relocations >> 2)) > (hashtable_size));
+
+ hashtable_bits += should_double_size;
+
+ hashtable_size <<= should_double_size;
+
+ relocation_hashtable = kmalloc_array(hashtable_size,
+ sizeof(*relocation_hashtable),
+ GFP_KERNEL);
+ __hash_init(relocation_hashtable, hashtable_size);
+
+ INIT_LIST_HEAD(&used_buckets_list);
+
+ return hashtable_bits;
+}
+
int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
unsigned int symindex, unsigned int relsec,
struct module *me)
@@ -353,11 +736,13 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
unsigned int i, type;
Elf_Addr v;
int res;
+ unsigned int num_relocations = sechdrs[relsec].sh_size / sizeof(*rel);
+ unsigned int hashtable_bits = initialize_relocation_hashtable(num_relocations);
pr_debug("Applying relocate section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
- for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+ for (i = 0; i < num_relocations; i++) {
/* This is where to make the change */
location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ rel[i].r_offset;
@@ -375,8 +760,8 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
type = ELF_RISCV_R_TYPE(rel[i].r_info);
- if (type < ARRAY_SIZE(reloc_handlers_rela))
- handler = reloc_handlers_rela[type];
+ if (type < ARRAY_SIZE(reloc_handlers))
+ handler = reloc_handlers[type].reloc_handler;
else
handler = NULL;
@@ -432,11 +817,16 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
}
}
- res = handler(me, location, v);
+ if (reloc_handlers[type].accumulate_handler)
+ res = add_relocation_to_accumulate(me, type, location, hashtable_bits, v);
+ else
+ res = handler(me, location, v);
if (res)
return res;
}
+ process_accumulated_relocations(me);
+
return 0;
}
From af71bc194916b10f9b394f9b14419d99700a5e67 Mon Sep 17 00:00:00 2001
From: Charlie Jenkins <charlie@rivosinc.com>
Date: Wed, 1 Nov 2023 11:33:01 -0700
Subject: [PATCH 3/3] riscv: Add tests for riscv module loading
Add test cases for the two main groups of relocations added: SUB and
SET, along with uleb128.
Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20231101-module_relocations-v9-3-8dfa3483c400@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
---
arch/riscv/Kconfig.debug | 1 +
arch/riscv/kernel/Makefile | 1 +
arch/riscv/kernel/tests/Kconfig.debug | 35 ++++++++
arch/riscv/kernel/tests/Makefile | 1 +
arch/riscv/kernel/tests/module_test/Makefile | 15 ++++
.../module_test/test_module_linking_main.c | 88 +++++++++++++++++++
.../kernel/tests/module_test/test_set16.S | 23 +++++
.../kernel/tests/module_test/test_set32.S | 20 +++++
.../kernel/tests/module_test/test_set6.S | 23 +++++
.../kernel/tests/module_test/test_set8.S | 23 +++++
.../kernel/tests/module_test/test_sub16.S | 20 +++++
.../kernel/tests/module_test/test_sub32.S | 20 +++++
.../kernel/tests/module_test/test_sub6.S | 20 +++++
.../kernel/tests/module_test/test_sub64.S | 25 ++++++
.../kernel/tests/module_test/test_sub8.S | 20 +++++
.../kernel/tests/module_test/test_uleb128.S | 31 +++++++
16 files changed, 366 insertions(+)
create mode 100644 arch/riscv/kernel/tests/Kconfig.debug
create mode 100644 arch/riscv/kernel/tests/Makefile
create mode 100644 arch/riscv/kernel/tests/module_test/Makefile
create mode 100644 arch/riscv/kernel/tests/module_test/test_module_linking_main.c
create mode 100644 arch/riscv/kernel/tests/module_test/test_set16.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_set32.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_set6.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_set8.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_sub16.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_sub32.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_sub6.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_sub64.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_sub8.S
create mode 100644 arch/riscv/kernel/tests/module_test/test_uleb128.S
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..5dba64e8e977
--- /dev/null
+++ b/arch/riscv/kernel/tests/Kconfig.debug
@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menu "arch/riscv/kernel Testing and Coverage"
+
+config AS_HAS_ULEB128
+ def_bool $(as-instr,.reloc label$(comma) R_RISCV_SET_ULEB128$(comma) 127\n.reloc label$(comma) R_RISCV_SUB_ULEB128$(comma) 127\nlabel:\n.word 0)
+
+menuconfig RUNTIME_KERNEL_TESTING_MENU
+ bool "arch/riscv/kernel runtime Testing"
+ def_bool y
+ help
+ Enable riscv kernel runtime testing.
+
+if RUNTIME_KERNEL_TESTING_MENU
+
+config RISCV_MODULE_LINKING_KUNIT
+ bool "KUnit test riscv module linking at runtime" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ Enable this option to test riscv module linking at boot. This will
+ enable a module called "test_module_linking".
+
+ KUnit tests run during boot and output the results to the debug log
+ in TAP format (http://testanything.org/). Only useful for kernel devs
+ running the KUnit test harness, and not intended for inclusion into a
+ production build.
+
+ For more information on KUnit and unit tests in general please refer
+ to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+ If unsure, say N.
+
+endif # RUNTIME_TESTING_MENU
+
+endmenu # "arch/riscv/kernel runtime Testing"
diff --git a/arch/riscv/kernel/tests/Makefile b/arch/riscv/kernel/tests/Makefile
new file mode 100644
index 000000000000..7d6c76cffe20
--- /dev/null
+++ b/arch/riscv/kernel/tests/Makefile
@@ -0,0 +1 @@
+obj-$(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..d7a6fd8943de
--- /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_module_linking-objs += $(test_sub)
+
+test_module_linking-objs += $(test_set)
+
+ifeq ($(CONFIG_AS_HAS_ULEB128),y)
+test_module_linking-objs += test_uleb128.o
+endif
+
+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..8df5fa5b834e
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_module_linking_main.c
@@ -0,0 +1,88 @@
+// 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);
+
+#ifdef CONFIG_AS_HAS_ULEB128
+extern int test_uleb_basic(void);
+extern int test_uleb_large(void);
+#endif
+
+#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);
+}
+
+#ifdef CONFIG_AS_HAS_ULEB128
+void run_test_uleb(struct kunit *test)
+{
+ int val_uleb = test_uleb_basic();
+ int val_uleb2 = test_uleb_large();
+
+ CHECK_EQ(val_uleb, 0);
+ CHECK_EQ(val_uleb2, 0);
+}
+#endif
+
+static struct kunit_case __refdata riscv_module_linking_test_cases[] = {
+ KUNIT_CASE(run_test_set),
+ KUNIT_CASE(run_test_sub),
+#ifdef CONFIG_AS_HAS_ULEB128
+ KUNIT_CASE(run_test_uleb),
+#endif
+ {}
+};
+
+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..80f731d599ba
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub16.S
@@ -0,0 +1,20 @@
+/* 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:
+ .space 32
+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..a341686e12df
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub32.S
@@ -0,0 +1,20 @@
+/* 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:
+ .space 32
+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..e8b61c1ec527
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub6.S
@@ -0,0 +1,20 @@
+/* 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:
+ .space 32
+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..a59e8afa88fd
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub64.S
@@ -0,0 +1,25 @@
+/* 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:
+ .space 32
+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..ac5d0ec98de3
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_sub8.S
@@ -0,0 +1,20 @@
+/* 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:
+ .space 32
+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..90f22049d553
--- /dev/null
+++ b/arch/riscv/kernel/tests/module_test/test_uleb128.S
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023 Rivos Inc.
+ */
+
+.text
+.global test_uleb_basic
+test_uleb_basic:
+ ld a0, second
+ addi a0, a0, -127
+ ret
+
+.global test_uleb_large
+test_uleb_large:
+ ld a0, fourth
+ addi a0, a0, -0x07e8
+ ret
+
+.data
+first:
+ .space 127
+second:
+ .reloc second, R_RISCV_SET_ULEB128, second
+ .reloc second, R_RISCV_SUB_ULEB128, first
+ .dword 0
+third:
+ .space 1000
+fourth:
+ .reloc fourth, R_RISCV_SET_ULEB128, fourth
+ .reloc fourth, R_RISCV_SUB_ULEB128, third
+ .dword 0