// SPDX-License-Identifier: GPL-2.0-or-later/* *  Copyright 2008 Michael Ellerman, IBM Corporation. */ #include <linux/vmalloc.h>#include <linux/init.h> #include <asm/text-patching.h> static int __init 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;nop;\n");} #define check(x)	do {	\	if (!(x))		\		pr_err("code-patching: test failed at line %d\n", __LINE__); \} while (0) static void __init test_branch_iform(void){	int err;	ppc_inst_t 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)));	/* All bits of target set, and flags */	check(instr_is_branch_iform(ppc_inst(0x4bffffff)));	/* High bit of opcode set, which is wrong */	check(!instr_is_branch_iform(ppc_inst(0xcbffffff)));	/* Middle bits of opcode set, which is wrong */	check(!instr_is_branch_iform(ppc_inst(0x7bffffff))); 	/* Simplest case, branch to self with link */	check(instr_is_branch_iform(ppc_inst(0x48000001)));	/* All bits of targets set */	check(instr_is_branch_iform(ppc_inst(0x4bfffffd)));	/* Some bits of targets set */	check(instr_is_branch_iform(ppc_inst(0x4bff00fd)));	/* Must be a valid branch to start with */	check(!instr_is_branch_iform(ppc_inst(0x7bfffffd))); 	/* Absolute branch to 0x100 */	ppc_inst_write(iptr, ppc_inst(0x48000103));	check(instr_is_branch_to_addr(iptr, 0x100));	/* Absolute branch to 0x420fc */	ppc_inst_write(iptr, ppc_inst(0x480420ff));	check(instr_is_branch_to_addr(iptr, 0x420fc));	/* Maximum positive relative branch, + 20MB - 4B */	ppc_inst_write(iptr, ppc_inst(0x49fffffc));	check(instr_is_branch_to_addr(iptr, addr + 0x1FFFFFC));	/* Smallest negative relative branch, - 4B */	ppc_inst_write(iptr, ppc_inst(0x4bfffffc));	check(instr_is_branch_to_addr(iptr, addr - 4));	/* Largest negative relative branch, - 32 MB */	ppc_inst_write(iptr, ppc_inst(0x4a000000));	check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); 	/* Branch to self, with link */	err = create_branch(&instr, iptr, addr, BRANCH_SET_LINK);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr)); 	/* Branch to self - 0x100, with link */	err = create_branch(&instr, iptr, addr - 0x100, BRANCH_SET_LINK);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr - 0x100)); 	/* Branch to self + 0x100, no link */	err = create_branch(&instr, iptr, addr + 0x100, 0);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr + 0x100)); 	/* Maximum relative negative offset, - 32 MB */	err = create_branch(&instr, iptr, addr - 0x2000000, BRANCH_SET_LINK);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr - 0x2000000)); 	/* Out of range relative negative offset, - 32 MB + 4*/	err = create_branch(&instr, iptr, addr - 0x2000004, BRANCH_SET_LINK);	check(err); 	/* Out of range relative positive offset, + 32 MB */	err = create_branch(&instr, iptr, addr + 0x2000000, BRANCH_SET_LINK);	check(err); 	/* Unaligned target */	err = create_branch(&instr, iptr, addr + 3, BRANCH_SET_LINK);	check(err); 	/* Check flags are masked correctly */	err = create_branch(&instr, iptr, addr, 0xFFFFFFFC);	ppc_inst_write(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){	u32 *iptr;	unsigned long dest;	ppc_inst_t instr; 	/* Check we can create a function call */	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);	check(instr_is_branch_to_addr(iptr, dest));} static void __init test_branch_bform(void){	int err;	unsigned long addr;	ppc_inst_t instr;	u32 tmp[2];	u32 *iptr = tmp;	unsigned int flags; 	addr = (unsigned long)iptr; 	/* The simplest case, branch to self, no flags */	check(instr_is_branch_bform(ppc_inst(0x40000000)));	/* All bits of target set, and flags */	check(instr_is_branch_bform(ppc_inst(0x43ffffff)));	/* High bit of opcode set, which is wrong */	check(!instr_is_branch_bform(ppc_inst(0xc3ffffff)));	/* Middle bits of opcode set, which is wrong */	check(!instr_is_branch_bform(ppc_inst(0x7bffffff))); 	/* Absolute conditional branch to 0x100 */	ppc_inst_write(iptr, ppc_inst(0x43ff0103));	check(instr_is_branch_to_addr(iptr, 0x100));	/* Absolute conditional branch to 0x20fc */	ppc_inst_write(iptr, ppc_inst(0x43ff20ff));	check(instr_is_branch_to_addr(iptr, 0x20fc));	/* Maximum positive relative conditional branch, + 32 KB - 4B */	ppc_inst_write(iptr, ppc_inst(0x43ff7ffc));	check(instr_is_branch_to_addr(iptr, addr + 0x7FFC));	/* Smallest negative relative conditional branch, - 4B */	ppc_inst_write(iptr, ppc_inst(0x43fffffc));	check(instr_is_branch_to_addr(iptr, addr - 4));	/* Largest negative relative conditional branch, - 32 KB */	ppc_inst_write(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);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr)); 	/* Branch to self - 0x100 */	err = create_cond_branch(&instr, iptr, addr - 0x100, flags);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr - 0x100)); 	/* Branch to self + 0x100 */	err = create_cond_branch(&instr, iptr, addr + 0x100, flags);	ppc_inst_write(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);	ppc_inst_write(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);	check(err); 	/* Out of range relative positive offset, + 32 KB */	err = create_cond_branch(&instr, iptr, addr + 0x8000, flags);	check(err); 	/* Unaligned target */	err = create_cond_branch(&instr, iptr, addr + 3, flags);	check(err); 	/* Check flags are masked correctly */	err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC);	ppc_inst_write(iptr, instr);	check(instr_is_branch_to_addr(iptr, addr));	check(ppc_inst_equal(instr, ppc_inst(0x43FF0000)));} static void __init test_translate_branch(void){	unsigned long addr;	void *p, *q;	ppc_inst_t instr;	void *buf; 	buf = vmalloc(PAGE_ALIGN(0x2000000 + 1));	check(buf);	if (!buf)		return; 	/* Simple case, branch to self moved a little */	p = buf;	addr = (unsigned long)p;	create_branch(&instr, p, addr, 0);	ppc_inst_write(p, instr);	check(instr_is_branch_to_addr(p, addr));	q = p + 4;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(q, addr)); 	/* Maximum negative case, move b . to addr + 32 MB */	p = buf;	addr = (unsigned long)p;	create_branch(&instr, p, addr, 0);	ppc_inst_write(p, instr);	q = buf + 0x2000000;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr));	check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x4a000000))); 	/* Maximum positive case, move x to x - 32 MB + 4 */	p = buf + 0x2000000;	addr = (unsigned long)p;	create_branch(&instr, p, addr, 0);	ppc_inst_write(p, instr);	q = buf + 4;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr));	check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x49fffffc))); 	/* Jump to x + 16 MB moved to x + 20 MB */	p = buf;	addr = 0x1000000 + (unsigned long)buf;	create_branch(&instr, p, addr, BRANCH_SET_LINK);	ppc_inst_write(p, instr);	q = buf + 0x1400000;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr)); 	/* Jump to x + 16 MB moved to x - 16 MB + 4 */	p = buf + 0x1000000;	addr = 0x2000000 + (unsigned long)buf;	create_branch(&instr, p, addr, 0);	ppc_inst_write(p, instr);	q = buf + 4;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr));  	/* Conditional branch tests */ 	/* Simple case, branch to self moved a little */	p = buf;	addr = (unsigned long)p;	create_cond_branch(&instr, p, addr, 0);	ppc_inst_write(p, instr);	check(instr_is_branch_to_addr(p, addr));	q = buf + 4;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(q, addr)); 	/* Maximum negative case, move b . to addr + 32 KB */	p = buf;	addr = (unsigned long)p;	create_cond_branch(&instr, p, addr, 0xFFFFFFFC);	ppc_inst_write(p, instr);	q = buf + 0x8000;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr));	check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff8000))); 	/* Maximum positive case, move x to x - 32 KB + 4 */	p = buf + 0x8000;	addr = (unsigned long)p;	create_cond_branch(&instr, p, addr, 0xFFFFFFFC);	ppc_inst_write(p, instr);	q = buf + 4;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr));	check(ppc_inst_equal(ppc_inst_read(q), ppc_inst(0x43ff7ffc))); 	/* Jump to x + 12 KB moved to x + 20 KB */	p = buf;	addr = 0x3000 + (unsigned long)buf;	create_cond_branch(&instr, p, addr, BRANCH_SET_LINK);	ppc_inst_write(p, instr);	q = buf + 0x5000;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr)); 	/* Jump to x + 8 KB moved to x - 8 KB + 4 */	p = buf + 0x2000;	addr = 0x4000 + (unsigned long)buf;	create_cond_branch(&instr, p, addr, 0);	ppc_inst_write(p, instr);	q = buf + 4;	translate_branch(&instr, q, p);	ppc_inst_write(q, instr);	check(instr_is_branch_to_addr(p, addr));	check(instr_is_branch_to_addr(q, addr)); 	/* Free the buffer we were using */	vfree(buf);} static void __init test_prefixed_patching(void){	u32 *iptr = (u32 *)ppc_function_entry(test_trampoline);	u32 expected[2] = {OP_PREFIX << 26, 0};	ppc_inst_t inst = ppc_inst_prefix(OP_PREFIX << 26, 0); 	if (!IS_ENABLED(CONFIG_PPC64))		return; 	patch_instruction(iptr, inst); 	check(!memcmp(iptr, expected, sizeof(expected)));} static void __init test_multi_instruction_patching(void){	u32 code[32];	void *buf;	u32 *addr32;	u64 *addr64;	ppc_inst_t inst64 = ppc_inst_prefix(OP_PREFIX << 26 | 3UL << 24, PPC_RAW_TRAP());	u32 inst32 = PPC_RAW_NOP(); 	buf = vzalloc(PAGE_SIZE * 8);	check(buf);	if (!buf)		return; 	/* Test single page 32-bit repeated instruction */	addr32 = buf + PAGE_SIZE;	check(!patch_instructions(addr32 + 1, &inst32, 12, true)); 	check(addr32[0] == 0);	check(addr32[1] == inst32);	check(addr32[2] == inst32);	check(addr32[3] == inst32);	check(addr32[4] == 0); 	/* Test single page 64-bit repeated instruction */	if (IS_ENABLED(CONFIG_PPC64)) {		check(ppc_inst_prefixed(inst64)); 		addr64 = buf + PAGE_SIZE * 2;		ppc_inst_write(code, inst64);		check(!patch_instructions((u32 *)(addr64 + 1), code, 24, true)); 		check(addr64[0] == 0);		check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[1]), inst64));		check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[2]), inst64));		check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[3]), inst64));		check(addr64[4] == 0);	} 	/* Test single page memcpy */	addr32 = buf + PAGE_SIZE * 3; 	for (int i = 0; i < ARRAY_SIZE(code); i++)		code[i] = i + 1; 	check(!patch_instructions(addr32 + 1, code, sizeof(code), false)); 	check(addr32[0] == 0);	check(!memcmp(&addr32[1], code, sizeof(code)));	check(addr32[ARRAY_SIZE(code) + 1] == 0); 	/* Test multipage 32-bit repeated instruction */	addr32 = buf + PAGE_SIZE * 4 - 8;	check(!patch_instructions(addr32 + 1, &inst32, 12, true)); 	check(addr32[0] == 0);	check(addr32[1] == inst32);	check(addr32[2] == inst32);	check(addr32[3] == inst32);	check(addr32[4] == 0); 	/* Test multipage 64-bit repeated instruction */	if (IS_ENABLED(CONFIG_PPC64)) {		check(ppc_inst_prefixed(inst64)); 		addr64 = buf + PAGE_SIZE * 5 - 8;		ppc_inst_write(code, inst64);		check(!patch_instructions((u32 *)(addr64 + 1), code, 24, true)); 		check(addr64[0] == 0);		check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[1]), inst64));		check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[2]), inst64));		check(ppc_inst_equal(ppc_inst_read((u32 *)&addr64[3]), inst64));		check(addr64[4] == 0);	} 	/* Test multipage memcpy */	addr32 = buf + PAGE_SIZE * 6 - 12; 	for (int i = 0; i < ARRAY_SIZE(code); i++)		code[i] = i + 1; 	check(!patch_instructions(addr32 + 1, code, sizeof(code), false)); 	check(addr32[0] == 0);	check(!memcmp(&addr32[1], code, sizeof(code)));	check(addr32[ARRAY_SIZE(code) + 1] == 0); 	vfree(buf);} static void __init test_data_patching(void){	void *buf;	u32 *addr32; 	buf = vzalloc(PAGE_SIZE);	check(buf);	if (!buf)		return; 	addr32 = buf + 128; 	addr32[1] = 0xA0A1A2A3;	addr32[2] = 0xB0B1B2B3; 	check(!patch_uint(&addr32[1], 0xC0C1C2C3)); 	check(addr32[0] == 0);	check(addr32[1] == 0xC0C1C2C3);	check(addr32[2] == 0xB0B1B2B3);	check(addr32[3] == 0); 	/* Unaligned patch_ulong() should fail */	if (IS_ENABLED(CONFIG_PPC64))		check(patch_ulong(&addr32[1], 0xD0D1D2D3) == -EINVAL); 	check(!patch_ulong(&addr32[2], 0xD0D1D2D3)); 	check(addr32[0] == 0);	check(addr32[1] == 0xC0C1C2C3);	check(*(unsigned long *)(&addr32[2]) == 0xD0D1D2D3); 	if (!IS_ENABLED(CONFIG_PPC64))		check(addr32[3] == 0); 	check(addr32[4] == 0); 	vfree(buf);} static int __init test_code_patching(void){	pr_info("Running code patching self-tests ...\n"); 	test_branch_iform();	test_branch_bform();	test_create_function_call();	test_translate_branch();	test_prefixed_patching();	test_multi_instruction_patching();	test_data_patching(); 	return 0;}late_initcall(test_code_patching);