| Message ID | 20231016-module_relocations-v3-1-a667fd6071e9@rivosinc.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | riscv: Add remaining module relocations and tests | expand |
On Okt 16 2023, Charlie Jenkins wrote: > @@ -81,7 +82,7 @@ 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_RVC_LUI 46 The latest ELF psABI defines 46 as reserved.
On Mon, Oct 16, 2023 at 10:36:09AM -0700, Charlie Jenkins wrote: > Add all final module relocations and add error logs explaining the ones > that are not supported. In the patchwork automation's clang/llvm allmodconfig: ../arch/riscv/kernel/tests/module_test/test_uleb128.S:18:17: error: unknown relocation name ../arch/riscv/kernel/tests/module_test/test_uleb128.S:19:17: error: unknown relocation name (llvm-17 iirc) Cheers, Conor. > > Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> > --- > arch/riscv/include/uapi/asm/elf.h | 6 +- > arch/riscv/kernel/module.c | 207 +++++++++++++++++++++++++++++++++----- > 2 files changed, 187 insertions(+), 26 deletions(-) > > diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h > index d696d6610231..a9307a1c9ceb 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 +82,7 @@ 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_RVC_LUI 46 > #define R_RISCV_GPREL_I 47 > #define R_RISCV_GPREL_S 48 > #define R_RISCV_TPREL_I 49 > @@ -93,6 +94,9 @@ 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 7c651d55fcbd..73f47de538d2 100644 > --- a/arch/riscv/kernel/module.c > +++ b/arch/riscv/kernel/module.c > @@ -7,6 +7,7 @@ > #include <linux/elf.h> > #include <linux/err.h> > #include <linux/errno.h> > +#include <linux/kernel.h> > #include <linux/moduleloader.h> > #include <linux/vmalloc.h> > #include <linux/sizes.h> > @@ -268,6 +269,12 @@ static int apply_r_riscv_align_rela(struct module *me, u32 *location, > return -EINVAL; > } > > +static int apply_r_riscv_add8_rela(struct module *me, u32 *location, Elf_Addr v) > +{ > + *(u8 *)location += (u8)v; > + return 0; > +} > + > static int apply_r_riscv_add16_rela(struct module *me, u32 *location, > Elf_Addr v) > { > @@ -289,6 +296,12 @@ static int apply_r_riscv_add64_rela(struct module *me, u32 *location, > return 0; > } > > +static int apply_r_riscv_sub8_rela(struct module *me, u32 *location, Elf_Addr v) > +{ > + *(u8 *)location -= (u8)v; > + return 0; > +} > + > static int apply_r_riscv_sub16_rela(struct module *me, u32 *location, > Elf_Addr v) > { > @@ -310,31 +323,149 @@ static int apply_r_riscv_sub64_rela(struct module *me, u32 *location, > return 0; > } > > -static int (*reloc_handlers_rela[]) (struct module *me, u32 *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, u32 *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, u32 *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, u32 *location, Elf_Addr v) > +{ > + *(u8 *)location -= (u8)v & 0x3F; > + return 0; > +} > + > +static int apply_r_riscv_set6_rela(struct module *me, u32 *location, Elf_Addr v) > +{ > + *(u8 *)location = (*(u8 *)location & 0xc0) | ((u8)v & 0x3F); > + return 0; > +} > + > +static int apply_r_riscv_set8_rela(struct module *me, u32 *location, Elf_Addr v) > +{ > + *(u8 *)location = (u8)v; > + return 0; > +} > + > +static int apply_r_riscv_set16_rela(struct module *me, u32 *location, > + Elf_Addr v) > +{ > + *(u16 *)location = (u16)v; > + return 0; > +} > + > +static int apply_r_riscv_set32_rela(struct module *me, u32 *location, > + Elf_Addr v) > +{ > + *(u32 *)location = (u32)v; > + return 0; > +} > + > +static int apply_r_riscv_32_pcrel_rela(struct module *me, u32 *location, > + Elf_Addr v) > +{ > + *(u32 *)location = (u32)v; > + return 0; > +} > + > +static int apply_r_riscv_plt32_rela(struct module *me, u32 *location, > + Elf_Addr v) > +{ > + *(u32 *)location = (u32)v; > + return 0; > +} > + > +static int apply_r_riscv_set_uleb128(struct module *me, u32 *location, Elf_Addr v) > +{ > + /* > + * Relocation is only performed if R_RISCV_SET_ULEB128 is followed by > + * R_RISCV_SUB_ULEB128 so do computation there > + */ > + return 0; > +} > + > +static int apply_r_riscv_sub_uleb128(struct module *me, u32 *location, Elf_Addr v) > +{ > + if (v >= 128) { > + pr_err("%s: uleb128 must be in [0, 127] (not %ld) at PC = %p\n", > + me->name, (unsigned long)v, location); > + return -EINVAL; > + } > + > + *location = v; > + return 0; > +} > + > +/* > + * Relocations defined in the riscv-elf-psabi-doc. > + * This handles static linking only. > + */ > +static int (*reloc_handlers_rela[])(struct module *me, u32 *location, > + Elf_Addr v) = { > + [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, > + [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_SUB8] = apply_r_riscv_sub8_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, > + /* 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, > + [R_RISCV_SET6] = apply_r_riscv_set6_rela, > + [R_RISCV_SET8] = apply_r_riscv_set8_rela, > + [R_RISCV_SET16] = apply_r_riscv_set16_rela, > + [R_RISCV_SET32] = apply_r_riscv_set32_rela, > + [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, > + [R_RISCV_SUB_ULEB128] = apply_r_riscv_sub_uleb128, > + /* 62-191 reserved for future standard use */ > + /* 192-255 nonstandard ABI extensions */ > }; > > int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > @@ -348,6 +479,10 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > unsigned int i, type; > Elf_Addr v; > int res; > + bool uleb128_set_exists = false; > + u32 *uleb128_set_loc; > + unsigned long uleb128_set_sym_val; > + > > pr_debug("Applying relocate section %u to %u\n", relsec, > sechdrs[relsec].sh_info); > @@ -425,6 +560,28 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > me->name); > return -EINVAL; > } > + } else if (type == R_RISCV_SET_ULEB128) { > + if (uleb128_set_exists) { > + pr_err("%s: riscv psABI requires the next ULEB128 relocation to come after a R_RISCV_SET_ULEB128 is an R_RISCV_SUB_ULEB128, not another R_RISCV_SET_ULEB128.\n", > + me->name); > + return -EINVAL; > + } > + uleb128_set_exists = true; > + uleb128_set_loc = location; > + uleb128_set_sym_val = > + ((Elf_Sym *)sechdrs[symindex].sh_addr + > + ELF_RISCV_R_SYM(rel[i].r_info)) > + ->st_value + > + rel[i].r_addend; > + } else if (type == R_RISCV_SUB_ULEB128) { > + if (uleb128_set_exists && uleb128_set_loc == location) { > + /* Calculate set and subtraction */ > + v = uleb128_set_sym_val - v; > + } else { > + pr_err("%s: R_RISCV_SUB_ULEB128 must always be paired with the first R_RISCV_SET_ULEB128 that comes before it. PC = %p\n", > + me->name, location); > + return -EINVAL; > + } > } > > res = handler(me, location, v); > > -- > 2.42.0 >
On Tue, Oct 17, 2023 at 08:08:26AM +0100, Conor Dooley wrote: > On Mon, Oct 16, 2023 at 10:36:09AM -0700, Charlie Jenkins wrote: > > Add all final module relocations and add error logs explaining the ones > > that are not supported. > > In the patchwork automation's clang/llvm allmodconfig: > ../arch/riscv/kernel/tests/module_test/test_uleb128.S:18:17: error: unknown relocation name > ../arch/riscv/kernel/tests/module_test/test_uleb128.S:19:17: error: unknown relocation name > > (llvm-17 iirc) > > Cheers, > Conor. Thank you, that slipped my mind that I needed to conditionally build the uleb128 tests. I will send an updated version. - Charlie > > > > > Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> > > --- > > arch/riscv/include/uapi/asm/elf.h | 6 +- > > arch/riscv/kernel/module.c | 207 +++++++++++++++++++++++++++++++++----- > > 2 files changed, 187 insertions(+), 26 deletions(-) > > > > diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h > > index d696d6610231..a9307a1c9ceb 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 +82,7 @@ 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_RVC_LUI 46 > > #define R_RISCV_GPREL_I 47 > > #define R_RISCV_GPREL_S 48 > > #define R_RISCV_TPREL_I 49 > > @@ -93,6 +94,9 @@ 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 7c651d55fcbd..73f47de538d2 100644 > > --- a/arch/riscv/kernel/module.c > > +++ b/arch/riscv/kernel/module.c > > @@ -7,6 +7,7 @@ > > #include <linux/elf.h> > > #include <linux/err.h> > > #include <linux/errno.h> > > +#include <linux/kernel.h> > > #include <linux/moduleloader.h> > > #include <linux/vmalloc.h> > > #include <linux/sizes.h> > > @@ -268,6 +269,12 @@ static int apply_r_riscv_align_rela(struct module *me, u32 *location, > > return -EINVAL; > > } > > > > +static int apply_r_riscv_add8_rela(struct module *me, u32 *location, Elf_Addr v) > > +{ > > + *(u8 *)location += (u8)v; > > + return 0; > > +} > > + > > static int apply_r_riscv_add16_rela(struct module *me, u32 *location, > > Elf_Addr v) > > { > > @@ -289,6 +296,12 @@ static int apply_r_riscv_add64_rela(struct module *me, u32 *location, > > return 0; > > } > > > > +static int apply_r_riscv_sub8_rela(struct module *me, u32 *location, Elf_Addr v) > > +{ > > + *(u8 *)location -= (u8)v; > > + return 0; > > +} > > + > > static int apply_r_riscv_sub16_rela(struct module *me, u32 *location, > > Elf_Addr v) > > { > > @@ -310,31 +323,149 @@ static int apply_r_riscv_sub64_rela(struct module *me, u32 *location, > > return 0; > > } > > > > -static int (*reloc_handlers_rela[]) (struct module *me, u32 *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, u32 *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, u32 *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, u32 *location, Elf_Addr v) > > +{ > > + *(u8 *)location -= (u8)v & 0x3F; > > + return 0; > > +} > > + > > +static int apply_r_riscv_set6_rela(struct module *me, u32 *location, Elf_Addr v) > > +{ > > + *(u8 *)location = (*(u8 *)location & 0xc0) | ((u8)v & 0x3F); > > + return 0; > > +} > > + > > +static int apply_r_riscv_set8_rela(struct module *me, u32 *location, Elf_Addr v) > > +{ > > + *(u8 *)location = (u8)v; > > + return 0; > > +} > > + > > +static int apply_r_riscv_set16_rela(struct module *me, u32 *location, > > + Elf_Addr v) > > +{ > > + *(u16 *)location = (u16)v; > > + return 0; > > +} > > + > > +static int apply_r_riscv_set32_rela(struct module *me, u32 *location, > > + Elf_Addr v) > > +{ > > + *(u32 *)location = (u32)v; > > + return 0; > > +} > > + > > +static int apply_r_riscv_32_pcrel_rela(struct module *me, u32 *location, > > + Elf_Addr v) > > +{ > > + *(u32 *)location = (u32)v; > > + return 0; > > +} > > + > > +static int apply_r_riscv_plt32_rela(struct module *me, u32 *location, > > + Elf_Addr v) > > +{ > > + *(u32 *)location = (u32)v; > > + return 0; > > +} > > + > > +static int apply_r_riscv_set_uleb128(struct module *me, u32 *location, Elf_Addr v) > > +{ > > + /* > > + * Relocation is only performed if R_RISCV_SET_ULEB128 is followed by > > + * R_RISCV_SUB_ULEB128 so do computation there > > + */ > > + return 0; > > +} > > + > > +static int apply_r_riscv_sub_uleb128(struct module *me, u32 *location, Elf_Addr v) > > +{ > > + if (v >= 128) { > > + pr_err("%s: uleb128 must be in [0, 127] (not %ld) at PC = %p\n", > > + me->name, (unsigned long)v, location); > > + return -EINVAL; > > + } > > + > > + *location = v; > > + return 0; > > +} > > + > > +/* > > + * Relocations defined in the riscv-elf-psabi-doc. > > + * This handles static linking only. > > + */ > > +static int (*reloc_handlers_rela[])(struct module *me, u32 *location, > > + Elf_Addr v) = { > > + [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, > > + [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_SUB8] = apply_r_riscv_sub8_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, > > + /* 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, > > + [R_RISCV_SET6] = apply_r_riscv_set6_rela, > > + [R_RISCV_SET8] = apply_r_riscv_set8_rela, > > + [R_RISCV_SET16] = apply_r_riscv_set16_rela, > > + [R_RISCV_SET32] = apply_r_riscv_set32_rela, > > + [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, > > + [R_RISCV_SUB_ULEB128] = apply_r_riscv_sub_uleb128, > > + /* 62-191 reserved for future standard use */ > > + /* 192-255 nonstandard ABI extensions */ > > }; > > > > int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > > @@ -348,6 +479,10 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > > unsigned int i, type; > > Elf_Addr v; > > int res; > > + bool uleb128_set_exists = false; > > + u32 *uleb128_set_loc; > > + unsigned long uleb128_set_sym_val; > > + > > > > pr_debug("Applying relocate section %u to %u\n", relsec, > > sechdrs[relsec].sh_info); > > @@ -425,6 +560,28 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, > > me->name); > > return -EINVAL; > > } > > + } else if (type == R_RISCV_SET_ULEB128) { > > + if (uleb128_set_exists) { > > + pr_err("%s: riscv psABI requires the next ULEB128 relocation to come after a R_RISCV_SET_ULEB128 is an R_RISCV_SUB_ULEB128, not another R_RISCV_SET_ULEB128.\n", > > + me->name); > > + return -EINVAL; > > + } > > + uleb128_set_exists = true; > > + uleb128_set_loc = location; > > + uleb128_set_sym_val = > > + ((Elf_Sym *)sechdrs[symindex].sh_addr + > > + ELF_RISCV_R_SYM(rel[i].r_info)) > > + ->st_value + > > + rel[i].r_addend; > > + } else if (type == R_RISCV_SUB_ULEB128) { > > + if (uleb128_set_exists && uleb128_set_loc == location) { > > + /* Calculate set and subtraction */ > > + v = uleb128_set_sym_val - v; > > + } else { > > + pr_err("%s: R_RISCV_SUB_ULEB128 must always be paired with the first R_RISCV_SET_ULEB128 that comes before it. PC = %p\n", > > + me->name, location); > > + return -EINVAL; > > + } > > } > > > > res = handler(me, location, v); > > > > -- > > 2.42.0 > >
diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h index d696d6610231..a9307a1c9ceb 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 +82,7 @@ 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_RVC_LUI 46 #define R_RISCV_GPREL_I 47 #define R_RISCV_GPREL_S 48 #define R_RISCV_TPREL_I 49 @@ -93,6 +94,9 @@ 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 7c651d55fcbd..73f47de538d2 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -7,6 +7,7 @@ #include <linux/elf.h> #include <linux/err.h> #include <linux/errno.h> +#include <linux/kernel.h> #include <linux/moduleloader.h> #include <linux/vmalloc.h> #include <linux/sizes.h> @@ -268,6 +269,12 @@ static int apply_r_riscv_align_rela(struct module *me, u32 *location, return -EINVAL; } +static int apply_r_riscv_add8_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *(u8 *)location += (u8)v; + return 0; +} + static int apply_r_riscv_add16_rela(struct module *me, u32 *location, Elf_Addr v) { @@ -289,6 +296,12 @@ static int apply_r_riscv_add64_rela(struct module *me, u32 *location, return 0; } +static int apply_r_riscv_sub8_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *(u8 *)location -= (u8)v; + return 0; +} + static int apply_r_riscv_sub16_rela(struct module *me, u32 *location, Elf_Addr v) { @@ -310,31 +323,149 @@ static int apply_r_riscv_sub64_rela(struct module *me, u32 *location, return 0; } -static int (*reloc_handlers_rela[]) (struct module *me, u32 *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, u32 *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, u32 *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, u32 *location, Elf_Addr v) +{ + *(u8 *)location -= (u8)v & 0x3F; + return 0; +} + +static int apply_r_riscv_set6_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *(u8 *)location = (*(u8 *)location & 0xc0) | ((u8)v & 0x3F); + return 0; +} + +static int apply_r_riscv_set8_rela(struct module *me, u32 *location, Elf_Addr v) +{ + *(u8 *)location = (u8)v; + return 0; +} + +static int apply_r_riscv_set16_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *(u16 *)location = (u16)v; + return 0; +} + +static int apply_r_riscv_set32_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *(u32 *)location = (u32)v; + return 0; +} + +static int apply_r_riscv_32_pcrel_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *(u32 *)location = (u32)v; + return 0; +} + +static int apply_r_riscv_plt32_rela(struct module *me, u32 *location, + Elf_Addr v) +{ + *(u32 *)location = (u32)v; + return 0; +} + +static int apply_r_riscv_set_uleb128(struct module *me, u32 *location, Elf_Addr v) +{ + /* + * Relocation is only performed if R_RISCV_SET_ULEB128 is followed by + * R_RISCV_SUB_ULEB128 so do computation there + */ + return 0; +} + +static int apply_r_riscv_sub_uleb128(struct module *me, u32 *location, Elf_Addr v) +{ + if (v >= 128) { + pr_err("%s: uleb128 must be in [0, 127] (not %ld) at PC = %p\n", + me->name, (unsigned long)v, location); + return -EINVAL; + } + + *location = v; + return 0; +} + +/* + * Relocations defined in the riscv-elf-psabi-doc. + * This handles static linking only. + */ +static int (*reloc_handlers_rela[])(struct module *me, u32 *location, + Elf_Addr v) = { + [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, + [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_SUB8] = apply_r_riscv_sub8_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, + /* 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, + [R_RISCV_SET6] = apply_r_riscv_set6_rela, + [R_RISCV_SET8] = apply_r_riscv_set8_rela, + [R_RISCV_SET16] = apply_r_riscv_set16_rela, + [R_RISCV_SET32] = apply_r_riscv_set32_rela, + [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, + [R_RISCV_SUB_ULEB128] = apply_r_riscv_sub_uleb128, + /* 62-191 reserved for future standard use */ + /* 192-255 nonstandard ABI extensions */ }; int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, @@ -348,6 +479,10 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, unsigned int i, type; Elf_Addr v; int res; + bool uleb128_set_exists = false; + u32 *uleb128_set_loc; + unsigned long uleb128_set_sym_val; + pr_debug("Applying relocate section %u to %u\n", relsec, sechdrs[relsec].sh_info); @@ -425,6 +560,28 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, me->name); return -EINVAL; } + } else if (type == R_RISCV_SET_ULEB128) { + if (uleb128_set_exists) { + pr_err("%s: riscv psABI requires the next ULEB128 relocation to come after a R_RISCV_SET_ULEB128 is an R_RISCV_SUB_ULEB128, not another R_RISCV_SET_ULEB128.\n", + me->name); + return -EINVAL; + } + uleb128_set_exists = true; + uleb128_set_loc = location; + uleb128_set_sym_val = + ((Elf_Sym *)sechdrs[symindex].sh_addr + + ELF_RISCV_R_SYM(rel[i].r_info)) + ->st_value + + rel[i].r_addend; + } else if (type == R_RISCV_SUB_ULEB128) { + if (uleb128_set_exists && uleb128_set_loc == location) { + /* Calculate set and subtraction */ + v = uleb128_set_sym_val - v; + } else { + pr_err("%s: R_RISCV_SUB_ULEB128 must always be paired with the first R_RISCV_SET_ULEB128 that comes before it. PC = %p\n", + me->name, location); + return -EINVAL; + } } res = handler(me, location, v);
Add all final module relocations and add error logs explaining the ones that are not supported. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> --- arch/riscv/include/uapi/asm/elf.h | 6 +- arch/riscv/kernel/module.c | 207 +++++++++++++++++++++++++++++++++----- 2 files changed, 187 insertions(+), 26 deletions(-)