diff options
Diffstat (limited to 'arch/powerpc/lib/code-patching.c')
| -rw-r--r-- | arch/powerpc/lib/code-patching.c | 178 |
1 files changed, 90 insertions, 88 deletions
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 870b30d9be2f..f9a3019e37b4 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -18,8 +18,7 @@ #include <asm/setup.h> #include <asm/inst.h> -static int __patch_instruction(struct ppc_inst *exec_addr, struct ppc_inst instr, - struct ppc_inst *patch_addr) +static int __patch_instruction(u32 *exec_addr, struct ppc_inst instr, u32 *patch_addr) { if (!ppc_inst_prefixed(instr)) { u32 val = ppc_inst_val(instr); @@ -40,7 +39,7 @@ failed: return -EFAULT; } -int raw_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr) +int raw_patch_instruction(u32 *addr, struct ppc_inst instr) { return __patch_instruction(addr, instr, addr); } @@ -70,22 +69,16 @@ static int text_area_cpu_down(unsigned int cpu) } /* - * Run as a late init call. This allows all the boot time patching to be done - * simply by patching the code, and then we're called here prior to - * mark_rodata_ro(), which happens after all init calls are run. Although - * BUG_ON() is rude, in this case it should only happen if ENOMEM, and we judge - * it as being preferable to a kernel that will crash later when someone tries - * to use patch_instruction(). + * Although BUG_ON() is rude, in this case it should only happen if ENOMEM, and + * we judge it as being preferable to a kernel that will crash later when + * someone tries to use patch_instruction(). */ -static int __init setup_text_poke_area(void) +void __init poking_init(void) { BUG_ON(!cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "powerpc/text_poke:online", text_area_cpu_up, text_area_cpu_down)); - - return 0; } -late_initcall(setup_text_poke_area); /* * This can be called for kernel text or a module. @@ -148,10 +141,10 @@ static inline int unmap_patch_area(unsigned long addr) return 0; } -static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr) +static int do_patch_instruction(u32 *addr, struct ppc_inst instr) { int err; - struct ppc_inst *patch_addr = NULL; + u32 *patch_addr = NULL; unsigned long flags; unsigned long text_poke_addr; unsigned long kaddr = (unsigned long)addr; @@ -172,7 +165,7 @@ static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr) goto out; } - patch_addr = (struct ppc_inst *)(text_poke_addr + (kaddr & ~PAGE_MASK)); + patch_addr = (u32 *)(text_poke_addr + (kaddr & ~PAGE_MASK)); __patch_instruction(addr, instr, patch_addr); @@ -187,14 +180,14 @@ out: } #else /* !CONFIG_STRICT_KERNEL_RWX */ -static int do_patch_instruction(struct ppc_inst *addr, struct ppc_inst instr) +static int do_patch_instruction(u32 *addr, struct ppc_inst instr) { return raw_patch_instruction(addr, instr); } #endif /* CONFIG_STRICT_KERNEL_RWX */ -int patch_instruction(struct ppc_inst *addr, struct ppc_inst instr) +int patch_instruction(u32 *addr, struct ppc_inst instr) { /* Make sure we aren't patching a freed init section */ if (init_mem_is_free && init_section_contains(addr, 4)) { @@ -205,7 +198,7 @@ int patch_instruction(struct ppc_inst *addr, struct ppc_inst instr) } NOKPROBE_SYMBOL(patch_instruction); -int patch_branch(struct ppc_inst *addr, unsigned long target, int flags) +int patch_branch(u32 *addr, unsigned long target, int flags) { struct ppc_inst instr; @@ -257,8 +250,7 @@ bool is_conditional_branch(struct ppc_inst instr) } NOKPROBE_SYMBOL(is_conditional_branch); -int create_branch(struct ppc_inst *instr, - const struct ppc_inst *addr, +int create_branch(struct ppc_inst *instr, const u32 *addr, unsigned long target, int flags) { long offset; @@ -278,7 +270,7 @@ int create_branch(struct ppc_inst *instr, return 0; } -int create_cond_branch(struct ppc_inst *instr, const struct ppc_inst *addr, +int create_cond_branch(struct ppc_inst *instr, const u32 *addr, unsigned long target, int flags) { long offset; @@ -325,39 +317,39 @@ int instr_is_relative_link_branch(struct ppc_inst instr) return instr_is_relative_branch(instr) && (ppc_inst_val(instr) & BRANCH_SET_LINK); } -static unsigned long branch_iform_target(const struct ppc_inst *instr) +static unsigned long branch_iform_target(const u32 *instr) { signed long imm; - imm = ppc_inst_val(*instr) & 0x3FFFFFC; + imm = ppc_inst_val(ppc_inst_read(instr)) & 0x3FFFFFC; /* If the top bit of the immediate value is set this is negative */ if (imm & 0x2000000) imm -= 0x4000000; - if ((ppc_inst_val(*instr) & BRANCH_ABSOLUTE) == 0) + if ((ppc_inst_val(ppc_inst_read(instr)) & BRANCH_ABSOLUTE) == 0) imm += (unsigned long)instr; return (unsigned long)imm; } -static unsigned long branch_bform_target(const struct ppc_inst *instr) +static unsigned long branch_bform_target(const u32 *instr) { signed long imm; - imm = ppc_inst_val(*instr) & 0xFFFC; + imm = ppc_inst_val(ppc_inst_read(instr)) & 0xFFFC; /* If the top bit of the immediate value is set this is negative */ if (imm & 0x8000) imm -= 0x10000; - if ((ppc_inst_val(*instr) & BRANCH_ABSOLUTE) == 0) + if ((ppc_inst_val(ppc_inst_read(instr)) & BRANCH_ABSOLUTE) == 0) imm += (unsigned long)instr; return (unsigned long)imm; } -unsigned long branch_target(const struct ppc_inst *instr) +unsigned long branch_target(const u32 *instr) { if (instr_is_branch_iform(ppc_inst_read(instr))) return branch_iform_target(instr); @@ -367,17 +359,7 @@ unsigned long branch_target(const struct ppc_inst *instr) return 0; } -int instr_is_branch_to_addr(const struct ppc_inst *instr, unsigned long addr) -{ - if (instr_is_branch_iform(ppc_inst_read(instr)) || - instr_is_branch_bform(ppc_inst_read(instr))) - return branch_target(instr) == addr; - - return 0; -} - -int translate_branch(struct ppc_inst *instr, const struct ppc_inst *dest, - const struct ppc_inst *src) +int translate_branch(struct ppc_inst *instr, const u32 *dest, const u32 *src) { unsigned long target; target = branch_target(src); @@ -404,12 +386,21 @@ void __patch_exception(int exc, unsigned long addr) * instruction of the exception, not the first one */ - patch_branch((struct ppc_inst *)(ibase + (exc / 4) + 1), addr, 0); + patch_branch(ibase + (exc / 4) + 1, addr, 0); } #endif #ifdef CONFIG_CODE_PATCHING_SELFTEST +static int instr_is_branch_to_addr(const u32 *instr, unsigned long addr) +{ + if (instr_is_branch_iform(ppc_inst_read(instr)) || + instr_is_branch_bform(ppc_inst_read(instr))) + return branch_target(instr) == addr; + + return 0; +} + static void __init test_trampoline(void) { asm ("nop;\n"); @@ -422,9 +413,9 @@ static void __init test_branch_iform(void) { int err; struct ppc_inst instr; - unsigned long addr; - - addr = (unsigned long)&instr; + u32 tmp[2]; + u32 *iptr = tmp; + unsigned long addr = (unsigned long)tmp; /* The simplest case, branch to self, no flags */ check(instr_is_branch_iform(ppc_inst(0x48000000))); @@ -445,63 +436,68 @@ static void __init test_branch_iform(void) check(!instr_is_branch_iform(ppc_inst(0x7bfffffd))); /* Absolute branch to 0x100 */ - instr = ppc_inst(0x48000103); - check(instr_is_branch_to_addr(&instr, 0x100)); + patch_instruction(iptr, ppc_inst(0x48000103)); + check(instr_is_branch_to_addr(iptr, 0x100)); /* Absolute branch to 0x420fc */ - instr = ppc_inst(0x480420ff); - check(instr_is_branch_to_addr(&instr, 0x420fc)); + patch_instruction(iptr, ppc_inst(0x480420ff)); + check(instr_is_branch_to_addr(iptr, 0x420fc)); /* Maximum positive relative branch, + 20MB - 4B */ - instr = ppc_inst(0x49fffffc); - check(instr_is_branch_to_addr(&instr, addr + 0x1FFFFFC)); + patch_instruction(iptr, ppc_inst(0x49fffffc)); + check(instr_is_branch_to_addr(iptr, addr + 0x1FFFFFC)); /* Smallest negative relative branch, - 4B */ - instr = ppc_inst(0x4bfffffc); - check(instr_is_branch_to_addr(&instr, addr - 4)); + patch_instruction(iptr, ppc_inst(0x4bfffffc)); + check(instr_is_branch_to_addr(iptr, addr - 4)); /* Largest negative relative branch, - 32 MB */ - instr = ppc_inst(0x4a000000); - check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); + patch_instruction(iptr, ppc_inst(0x4a000000)); + check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); /* Branch to self, with link */ - err = create_branch(&instr, &instr, addr, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr)); + err = create_branch(&instr, iptr, addr, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); /* Branch to self - 0x100, with link */ - err = create_branch(&instr, &instr, addr - 0x100, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr - 0x100)); + err = create_branch(&instr, iptr, addr - 0x100, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x100)); /* Branch to self + 0x100, no link */ - err = create_branch(&instr, &instr, addr + 0x100, 0); - check(instr_is_branch_to_addr(&instr, addr + 0x100)); + err = create_branch(&instr, iptr, addr + 0x100, 0); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr + 0x100)); /* Maximum relative negative offset, - 32 MB */ - err = create_branch(&instr, &instr, addr - 0x2000000, BRANCH_SET_LINK); - check(instr_is_branch_to_addr(&instr, addr - 0x2000000)); + err = create_branch(&instr, iptr, addr - 0x2000000, BRANCH_SET_LINK); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); /* Out of range relative negative offset, - 32 MB + 4*/ - err = create_branch(&instr, &instr, addr - 0x2000004, BRANCH_SET_LINK); + err = create_branch(&instr, iptr, addr - 0x2000004, BRANCH_SET_LINK); check(err); /* Out of range relative positive offset, + 32 MB */ - err = create_branch(&instr, &instr, addr + 0x2000000, BRANCH_SET_LINK); + err = create_branch(&instr, iptr, addr + 0x2000000, BRANCH_SET_LINK); check(err); /* Unaligned target */ - err = create_branch(&instr, &instr, addr + 3, BRANCH_SET_LINK); + err = create_branch(&instr, iptr, addr + 3, BRANCH_SET_LINK); check(err); /* Check flags are masked correctly */ - err = create_branch(&instr, &instr, addr, 0xFFFFFFFC); - check(instr_is_branch_to_addr(&instr, addr)); + err = create_branch(&instr, iptr, addr, 0xFFFFFFFC); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); check(ppc_inst_equal(instr, ppc_inst(0x48000000))); } static void __init test_create_function_call(void) { - struct ppc_inst *iptr; + u32 *iptr; unsigned long dest; struct ppc_inst instr; /* Check we can create a function call */ - iptr = (struct ppc_inst *)ppc_function_entry(test_trampoline); + iptr = (u32 *)ppc_function_entry(test_trampoline); dest = ppc_function_entry(test_create_function_call); create_branch(&instr, iptr, dest, BRANCH_SET_LINK); patch_instruction(iptr, instr); @@ -512,10 +508,11 @@ static void __init test_branch_bform(void) { int err; unsigned long addr; - struct ppc_inst *iptr, instr; + struct ppc_inst instr; + u32 tmp[2]; + u32 *iptr = tmp; unsigned int flags; - iptr = &instr; addr = (unsigned long)iptr; /* The simplest case, branch to self, no flags */ @@ -528,39 +525,43 @@ static void __init test_branch_bform(void) check(!instr_is_branch_bform(ppc_inst(0x7bffffff))); /* Absolute conditional branch to 0x100 */ - instr = ppc_inst(0x43ff0103); - check(instr_is_branch_to_addr(&instr, 0x100)); + patch_instruction(iptr, ppc_inst(0x43ff0103)); + check(instr_is_branch_to_addr(iptr, 0x100)); /* Absolute conditional branch to 0x20fc */ - instr = ppc_inst(0x43ff20ff); - check(instr_is_branch_to_addr(&instr, 0x20fc)); + patch_instruction(iptr, ppc_inst(0x43ff20ff)); + check(instr_is_branch_to_addr(iptr, 0x20fc)); /* Maximum positive relative conditional branch, + 32 KB - 4B */ - instr = ppc_inst(0x43ff7ffc); - check(instr_is_branch_to_addr(&instr, addr + 0x7FFC)); + patch_instruction(iptr, ppc_inst(0x43ff7ffc)); + check(instr_is_branch_to_addr(iptr, addr + 0x7FFC)); /* Smallest negative relative conditional branch, - 4B */ - instr = ppc_inst(0x43fffffc); - check(instr_is_branch_to_addr(&instr, addr - 4)); + patch_instruction(iptr, ppc_inst(0x43fffffc)); + check(instr_is_branch_to_addr(iptr, addr - 4)); /* Largest negative relative conditional branch, - 32 KB */ - instr = ppc_inst(0x43ff8000); - check(instr_is_branch_to_addr(&instr, addr - 0x8000)); + patch_instruction(iptr, ppc_inst(0x43ff8000)); + check(instr_is_branch_to_addr(iptr, addr - 0x8000)); /* All condition code bits set & link */ flags = 0x3ff000 | BRANCH_SET_LINK; /* Branch to self */ err = create_cond_branch(&instr, iptr, addr, flags); - check(instr_is_branch_to_addr(&instr, addr)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); /* Branch to self - 0x100 */ err = create_cond_branch(&instr, iptr, addr - 0x100, flags); - check(instr_is_branch_to_addr(&instr, addr - 0x100)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x100)); /* Branch to self + 0x100 */ err = create_cond_branch(&instr, iptr, addr + 0x100, flags); - check(instr_is_branch_to_addr(&instr, addr + 0x100)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr + 0x100)); /* Maximum relative negative offset, - 32 KB */ err = create_cond_branch(&instr, iptr, addr - 0x8000, flags); - check(instr_is_branch_to_addr(&instr, addr - 0x8000)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr - 0x8000)); /* Out of range relative negative offset, - 32 KB + 4*/ err = create_cond_branch(&instr, iptr, addr - 0x8004, flags); @@ -576,7 +577,8 @@ static void __init test_branch_bform(void) /* Check flags are masked correctly */ err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC); - check(instr_is_branch_to_addr(&instr, addr)); + patch_instruction(iptr, instr); + check(instr_is_branch_to_addr(iptr, addr)); check(ppc_inst_equal(instr, ppc_inst(0x43FF0000))); } @@ -715,9 +717,9 @@ static void __init test_prefixed_patching(void) extern unsigned int code_patching_test1_expected[]; extern unsigned int end_code_patching_test1[]; - __patch_instruction((struct ppc_inst *)code_patching_test1, + __patch_instruction(code_patching_test1, ppc_inst_prefix(OP_PREFIX << 26, 0x00000000), - (struct ppc_inst *)code_patching_test1); + code_patching_test1); check(!memcmp(code_patching_test1, code_patching_test1_expected, |