On Wed, Nov 14, 2018 at 06:27:36PM +0100, Alexander Graf wrote: > This patch adds awareness of RISC-V relocations throughout the grub tools > as well as dynamic linkage and elf->PE relocation conversion support. > > Signed-off-by: Alexander Graf <ag...@suse.de> > > --- > > v2 -> v3: > > - Fix riscv32 target > --- > grub-core/kern/dl.c | 6 +- > grub-core/kern/riscv/dl.c | 335 > ++++++++++++++++++++++++++++++++++++++++++++ > include/grub/dl.h | 6 +- > util/grub-mkimagexx.c | 268 +++++++++++++++++++++++++++++++++++ > util/grub-module-verifier.c | 56 ++++++++ > 5 files changed, 666 insertions(+), 5 deletions(-) > create mode 100644 grub-core/kern/riscv/dl.c > > diff --git a/grub-core/kern/dl.c b/grub-core/kern/dl.c > index f8d58f029..48eb5e7b6 100644 > --- a/grub-core/kern/dl.c > +++ b/grub-core/kern/dl.c > @@ -225,7 +225,7 @@ grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e) > unsigned i; > const Elf_Shdr *s; > grub_size_t tsize = 0, talign = 1; > -#if !defined (__i386__) && !defined (__x86_64__) > +#if !defined (__i386__) && !defined (__x86_64__) && !defined(__riscv)
Could not we use __riscv__? > grub_size_t tramp; > grub_size_t got; > grub_err_t err; > @@ -241,7 +241,7 @@ grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e) > talign = s->sh_addralign; > } > > -#if !defined (__i386__) && !defined (__x86_64__) > +#if !defined (__i386__) && !defined (__x86_64__) && !defined(__riscv) > err = grub_arch_dl_get_tramp_got_size (e, &tramp, &got); > if (err) > return err; > @@ -304,7 +304,7 @@ grub_dl_load_segments (grub_dl_t mod, const Elf_Ehdr *e) > mod->segment = seg; > } > } > -#if !defined (__i386__) && !defined (__x86_64__) > +#if !defined (__i386__) && !defined (__x86_64__) && !defined(__riscv) > ptr = (char *) ALIGN_UP ((grub_addr_t) ptr, GRUB_ARCH_DL_TRAMP_ALIGN); > mod->tramp = ptr; > mod->trampptr = ptr; > diff --git a/grub-core/kern/riscv/dl.c b/grub-core/kern/riscv/dl.c > new file mode 100644 > index 000000000..503b67df1 > --- /dev/null > +++ b/grub-core/kern/riscv/dl.c > @@ -0,0 +1,335 @@ > +/* dl.c - arch-dependent part of loadable module support */ > +/* > + * GRUB -- GRand Unified Bootloader > + * Copyright (C) 2013 Free Software Foundation, Inc. s/2013/2018/ > + * > + * GRUB is free software: you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation, either version 3 of the License, or > + * (at your option) any later version. > + * > + * GRUB is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. > + */ > + > +#include <grub/dl.h> > +#include <grub/elf.h> > +#include <grub/misc.h> > +#include <grub/err.h> > +#include <grub/mm.h> > +#include <grub/i18n.h> > + > +#define LDR 0x58000050 > +#define BR 0xd61f0200 > + > + Please drop this empty line. > +/* > + * Check if EHDR is a valid ELF header. > + */ > +grub_err_t > +grub_arch_dl_check_header (void *ehdr) > +{ > + Elf_Ehdr *e = ehdr; > + > + /* Check the magic numbers. */ > + if (e->e_ident[EI_DATA] != ELFDATA2LSB || e->e_machine != EM_RISCV) > + return grub_error (GRUB_ERR_BAD_OS, > + N_("invalid arch-dependent ELF magic")); > + > + return GRUB_ERR_NONE; > +} > + > +#pragma GCC diagnostic ignored "-Wcast-align" Why? Could you add a comment here? > +/* Relocate symbols. */ > +grub_err_t > +grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr, > + Elf_Shdr *s, grub_dl_segment_t seg) > +{ > + Elf_Rel *rel, *max; > + > + for (rel = (Elf_Rel *) ((char *) ehdr + s->sh_offset), > + max = (Elf_Rel *) ((char *) rel + s->sh_size); > + rel < max; > + rel = (Elf_Rel *) ((char *) rel + s->sh_entsize)) > + { > + Elf_Sym *sym; > + void *place; > + grub_size_t sym_addr; > + > + if (rel->r_offset >= seg->size) > + return grub_error (GRUB_ERR_BAD_MODULE, > + "reloc offset is out of the segment"); > + > + sym = (Elf_Sym *) ((char *) mod->symtab > + + mod->symsize * ELF_R_SYM (rel->r_info)); > + > + sym_addr = sym->st_value; > + if (s->sh_type == SHT_RELA) > + sym_addr += ((Elf_Rela *) rel)->r_addend; > + > + place = (void *) ((grub_addr_t) seg->addr + rel->r_offset); > + > + switch (ELF_R_TYPE (rel->r_info)) > + { > + case R_RISCV_32: > + { > + grub_uint32_t *abs_place = place; > + > + grub_dprintf ("dl", " reloc_abs32 %p => 0x%016llx\n", > + place, (unsigned long long) sym_addr); > + > + *abs_place = (grub_uint32_t) sym_addr; > + } > + break; > + case R_RISCV_64: > + { > + grub_size_t *abs_place = place; > + > + grub_dprintf ("dl", " reloc_abs64 %p => 0x%016llx\n", > + place, (unsigned long long) sym_addr); > + > + *abs_place = (grub_size_t) sym_addr; > + } > + break; > + > + case R_RISCV_ADD8: > + { > + grub_uint8_t *abs_place = place; > + > + *abs_place += (grub_uint8_t) sym_addr; > + } > + break; > + case R_RISCV_ADD16: > + { > + grub_uint16_t *abs_place = place; > + > + *abs_place += (grub_uint16_t) sym_addr; > + } > + break; > + case R_RISCV_ADD32: > + { > + grub_uint32_t *abs_place = place; > + > + *abs_place += (grub_uint32_t) sym_addr; > + } > + break; > + case R_RISCV_ADD64: > + { > + grub_size_t *abs_place = place; > + > + *abs_place += (grub_size_t) sym_addr; > + } > + break; > + > + case R_RISCV_SUB8: > + { > + grub_uint8_t *abs_place = place; > + > + *abs_place -= (grub_uint8_t) sym_addr; > + } > + break; > + case R_RISCV_SUB16: > + { > + grub_uint16_t *abs_place = place; > + > + *abs_place -= (grub_uint16_t) sym_addr; > + } > + break; > + case R_RISCV_SUB32: > + { > + grub_uint32_t *abs_place = place; > + > + *abs_place -= (grub_uint32_t) sym_addr; > + } > + break; > + case R_RISCV_SUB64: > + { > + grub_size_t *abs_place = place; > + > + *abs_place -= (grub_size_t) sym_addr; > + } > + break; > + > + case R_RISCV_BRANCH: > + { > + grub_uint32_t *abs_place = place; > + grub_ssize_t off = sym_addr - (grub_addr_t) place; > + grub_uint32_t imm12 = (off & 0x1000) << (31 - 12); > + grub_uint32_t imm11 = (off & 0x800) >> (11 - 7); > + grub_uint32_t imm10_5 = (off & 0x7e0) << (30 - 10); > + grub_uint32_t imm4_1 = (off & 0x1e) << (11 - 4); > + *abs_place = (*abs_place & 0x1fff07f) > + | imm12 | imm11 | imm10_5 | imm4_1; Could not we use some constants instead of numbers here? If this does not make sense than please name the source of this numbers. > + } > + break; > + > + case R_RISCV_JAL: > + { > + grub_uint32_t *abs_place = place; > + grub_ssize_t off = sym_addr - (grub_addr_t) place; > + grub_uint32_t imm20 = (off & 0x100000) << (31 - 20); > + grub_uint32_t imm19_12 = (off & 0xff000); > + grub_uint32_t imm11 = (off & 0x800) << (20 - 11); > + grub_uint32_t imm10_1 = (off & 0x7fe) << (30 - 10); > + *abs_place = (*abs_place & 0xfff) > + | imm20 | imm19_12 | imm11 | imm10_1; Ditto. > + } > + break; > + > + case R_RISCV_CALL: > + { > + grub_uint32_t *abs_place = place; > + grub_ssize_t off = sym_addr - (grub_addr_t) place; > + grub_uint32_t hi20, lo12; > + > + if (off != (grub_int32_t) off) > + return grub_error (GRUB_ERR_BAD_MODULE, "relocation overflow"); > + > + hi20 = (off + 0x800) & 0xfffff000; > + lo12 = (off - hi20) & 0xfff; > + abs_place[0] = (abs_place[0] & 0xfff) | hi20; > + abs_place[1] = (abs_place[1] & 0xfffff) | (lo12 << 20); Ditto and below... > + } > + break; > + > + case R_RISCV_RVC_BRANCH: > + { > + grub_uint16_t *abs_place = place; > + grub_ssize_t off = sym_addr - (grub_addr_t) place; > + grub_uint16_t imm8 = (off & 0x100) << (12 - 8); > + grub_uint16_t imm7_6 = (off & 0xc0) >> (6 - 5); > + grub_uint16_t imm5 = (off & 0x20) >> (5 - 2); > + grub_uint16_t imm4_3 = (off & 0x18) << (12 - 5); > + grub_uint16_t imm2_1 = (off & 0x6) << (12 - 10); > + *abs_place = (*abs_place & 0xe383) > + | imm8 | imm7_6 | imm5 | imm4_3 | imm2_1; > + } > + break; > + > + case R_RISCV_RVC_JUMP: > + { > + grub_uint16_t *abs_place = place; > + grub_ssize_t off = sym_addr - (grub_addr_t) place; > + grub_uint16_t imm11 = (off & 0x800) << (12 - 11); > + grub_uint16_t imm10 = (off & 0x400) >> (10 - 8); > + grub_uint16_t imm9_8 = (off & 0x300) << (12 - 11); > + grub_uint16_t imm7 = (off & 0x80) >> (7 - 6); > + grub_uint16_t imm6 = (off & 0x40) << (12 - 11); > + grub_uint16_t imm5 = (off & 0x20) >> (5 - 2); > + grub_uint16_t imm4 = (off & 0x10) << (12 - 5); > + grub_uint16_t imm3_1 = (off & 0xe) << (12 - 10); > + *abs_place = ((*abs_place & 0xe003) > + | imm11 | imm10 | imm9_8 | imm7 | imm6 > + | imm5 | imm4 | imm3_1); > + } > + break; > + > + case R_RISCV_PCREL_HI20: > + { > + grub_uint32_t *abs_place = place; > + grub_ssize_t off = sym_addr - (grub_addr_t) place; > + grub_int32_t hi20; > + > + if (off != (grub_int32_t)off) > + return grub_error (GRUB_ERR_BAD_MODULE, "relocation overflow"); > + > + hi20 = (off + 0x800) & 0xfffff000; > + *abs_place = (*abs_place & 0xfff) | hi20; > + } > + break; > + > + case R_RISCV_PCREL_LO12_I: > + case R_RISCV_PCREL_LO12_S: > + { > + grub_uint32_t *t32 = place; > + Elf_Rela *rel2; > + /* Search backwards for matching HI20 reloc. */ Why "backwards"? > + for (rel2 = (Elf_Rela *) ((char *) rel - s->sh_entsize); > + (unsigned long)rel2 >= ((unsigned long)ehdr + s->sh_offset); > + rel2 = (Elf_Rela *) ((char *) rel2 - s->sh_entsize)) > + { > + Elf_Addr rel2_info; > + Elf_Addr rel2_offset; > + Elf_Addr rel2_sym_addr; > + Elf_Addr rel2_loc; > + grub_ssize_t rel2_off; > + grub_ssize_t off; > + Elf_Sym *sym2; > + > + rel2_offset = rel2->r_offset; > + rel2_info = rel2->r_info; > + rel2_loc = (grub_addr_t) seg->addr + rel2_offset; > + > + if (ELF_R_TYPE (rel2_info) == R_RISCV_PCREL_HI20 > + && rel2_loc == sym_addr) > + { > + sym2 = (Elf_Sym *) ((char *) mod->symtab > + + mod->symsize * ELF_R_SYM (rel2->r_info)); > + rel2_sym_addr = sym2->st_value; > + if (s->sh_type == SHT_RELA) > + rel2_sym_addr += ((Elf_Rela *) rel2)->r_addend; > + > + rel2_off = rel2_sym_addr - rel2_loc; > + off = rel2_off - ((rel2_off + 0x800) & 0xfffff000); > + > + if (ELF_R_TYPE (rel->r_info) == R_RISCV_PCREL_LO12_I) > + *t32 = (*t32 & 0xfffff) | (off & 0xfff) << 20; > + else > + { > + grub_uint32_t imm11_5 = (off & 0xfe0) << (31 - 11); > + grub_uint32_t imm4_0 = (off & 0x1f) << (11 - 4); > + *t32 = (*t32 & 0x1fff07f) | imm11_5 | imm4_0; > + } > + break; > + } > + } > + if ((unsigned long)rel2 < ((unsigned long)ehdr + s->sh_offset)) > + return grub_error (GRUB_ERR_BAD_MODULE, "cannot find matching > HI20 relocation"); > + } > + break; > + > + case R_RISCV_HI20: > + { > + grub_uint32_t *abs_place = place; > + *abs_place = (*abs_place & 0xfff) | > + (((grub_int32_t) sym_addr + 0x800) & 0xfffff000); > + } > + break; > + > + case R_RISCV_LO12_I: > + { > + grub_uint32_t *abs_place = place; > + grub_int32_t lo12 = (grub_int32_t) sym_addr - > + (((grub_int32_t) sym_addr + 0x800) & > 0xfffff000); > + *abs_place = (*abs_place & 0xfffff) | ((lo12 & 0xfff) << 20); > + } > + break; > + > + case R_RISCV_LO12_S: > + { > + grub_uint32_t *abs_place = place; > + grub_int32_t lo12 = (grub_int32_t) sym_addr - > + (((grub_int32_t) sym_addr + 0x800) & > 0xfffff000); > + grub_uint32_t imm11_5 = (lo12 & 0xfe0) << (31 - 11); > + grub_uint32_t imm4_0 = (lo12 & 0x1f) << (11 - 4); > + *abs_place = (*abs_place & 0x1fff07f) | imm11_5 | imm4_0; Again, why not constants? And below... Daniel _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
