From 6ac7897f08e04b47df3955d7691652e9d12d4068 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Wed, 14 Apr 2021 13:08:40 +0000 Subject: powerpc: Remove probe_user_read_inst() Its name comes from former probe_user_read() function. That function is now called copy_from_user_nofault(). probe_user_read_inst() uses copy_from_user_nofault() to read only a few bytes. It is suboptimal. It does the same as get_user_inst() but in addition disables page faults. But on the other hand, it is not used for the time being. So remove it for now. If one day it is really needed, we can give it a new name more in line with today's naming, and implement it using get_user_inst() Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/5f6f82572242a59bfee1e19a71194d8f7ef5fca4.1618405715.git.christophe.leroy@csgroup.eu --- arch/powerpc/lib/inst.c | 31 ------------------------------- 1 file changed, 31 deletions(-) (limited to 'arch/powerpc/lib/inst.c') diff --git a/arch/powerpc/lib/inst.c b/arch/powerpc/lib/inst.c index 9cc17eb62462..c57b3548de37 100644 --- a/arch/powerpc/lib/inst.c +++ b/arch/powerpc/lib/inst.c @@ -9,24 +9,6 @@ #include #ifdef CONFIG_PPC64 -int probe_user_read_inst(struct ppc_inst *inst, - struct ppc_inst __user *nip) -{ - unsigned int val, suffix; - int err; - - err = copy_from_user_nofault(&val, nip, sizeof(val)); - if (err) - return err; - if (get_op(val) == OP_PREFIX) { - err = copy_from_user_nofault(&suffix, (void __user *)nip + 4, 4); - *inst = ppc_inst_prefix(val, suffix); - } else { - *inst = ppc_inst(val); - } - return err; -} - int probe_kernel_read_inst(struct ppc_inst *inst, struct ppc_inst *src) { @@ -45,19 +27,6 @@ int probe_kernel_read_inst(struct ppc_inst *inst, return err; } #else /* !CONFIG_PPC64 */ -int probe_user_read_inst(struct ppc_inst *inst, - struct ppc_inst __user *nip) -{ - unsigned int val; - int err; - - err = copy_from_user_nofault(&val, nip, sizeof(val)); - if (!err) - *inst = ppc_inst(val); - - return err; -} - int probe_kernel_read_inst(struct ppc_inst *inst, struct ppc_inst *src) { -- cgit v1.2.3 From 6449078d50111c839bb7156c3b99b9def80eed42 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Wed, 14 Apr 2021 13:08:41 +0000 Subject: powerpc: Make probe_kernel_read_inst() common to PPC32 and PPC64 We have two independant versions of probe_kernel_read_inst(), one for PPC32 and one for PPC64. The PPC32 is identical to the first part of the PPC64 version. The remaining part of PPC64 version is not relevant for PPC32, but not contradictory, so we can easily have a common function with the PPC64 part opted out via a IS_ENABLED(CONFIG_PPC64). The only need is to add a version of ppc_inst_prefix() for PPC32. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/f7b9dfddef3b3760182c7e5466356c121a293dc9.1618405715.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/inst.h | 2 ++ arch/powerpc/lib/inst.c | 17 +---------------- 2 files changed, 3 insertions(+), 16 deletions(-) (limited to 'arch/powerpc/lib/inst.c') diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h index b7709470e8e9..539117b0a2dc 100644 --- a/arch/powerpc/include/asm/inst.h +++ b/arch/powerpc/include/asm/inst.h @@ -102,6 +102,8 @@ static inline bool ppc_inst_equal(struct ppc_inst x, struct ppc_inst y) #define ppc_inst(x) ((struct ppc_inst){ .val = x }) +#define ppc_inst_prefix(x, y) ppc_inst(x) + static inline bool ppc_inst_prefixed(struct ppc_inst x) { return false; diff --git a/arch/powerpc/lib/inst.c b/arch/powerpc/lib/inst.c index c57b3548de37..0dff3ac2d45f 100644 --- a/arch/powerpc/lib/inst.c +++ b/arch/powerpc/lib/inst.c @@ -8,7 +8,6 @@ #include #include -#ifdef CONFIG_PPC64 int probe_kernel_read_inst(struct ppc_inst *inst, struct ppc_inst *src) { @@ -18,7 +17,7 @@ int probe_kernel_read_inst(struct ppc_inst *inst, err = copy_from_kernel_nofault(&val, src, sizeof(val)); if (err) return err; - if (get_op(val) == OP_PREFIX) { + if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) { err = copy_from_kernel_nofault(&suffix, (void *)src + 4, 4); *inst = ppc_inst_prefix(val, suffix); } else { @@ -26,17 +25,3 @@ int probe_kernel_read_inst(struct ppc_inst *inst, } return err; } -#else /* !CONFIG_PPC64 */ -int probe_kernel_read_inst(struct ppc_inst *inst, - struct ppc_inst *src) -{ - unsigned int val; - int err; - - err = copy_from_kernel_nofault(&val, src, sizeof(val)); - if (!err) - *inst = ppc_inst(val); - - return err; -} -#endif /* CONFIG_PPC64 */ -- cgit v1.2.3 From 41d6cf68b5f611934bcc6a7d4a1a2d9bfd04b420 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Wed, 14 Apr 2021 13:08:42 +0000 Subject: powerpc: Rename probe_kernel_read_inst() When probe_kernel_read_inst() was created, it was to mimic probe_kernel_read() function. Since then, probe_kernel_read() has been renamed copy_from_kernel_nofault(). Rename probe_kernel_read_inst() into copy_inst_from_kernel_nofault(). Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/b783d1f7cdb8914992384a669a2af57051b6bdcf.1618405715.git.christophe.leroy@csgroup.eu --- arch/powerpc/include/asm/inst.h | 3 +-- arch/powerpc/kernel/align.c | 2 +- arch/powerpc/kernel/trace/ftrace.c | 22 +++++++++++----------- arch/powerpc/lib/inst.c | 3 +-- 4 files changed, 14 insertions(+), 16 deletions(-) (limited to 'arch/powerpc/lib/inst.c') diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h index 539117b0a2dc..268d3bd073c8 100644 --- a/arch/powerpc/include/asm/inst.h +++ b/arch/powerpc/include/asm/inst.h @@ -178,7 +178,6 @@ static inline char *__ppc_inst_as_str(char str[PPC_INST_STR_LEN], struct ppc_ins __str; \ }) -int probe_kernel_read_inst(struct ppc_inst *inst, - struct ppc_inst *src); +int copy_inst_from_kernel_nofault(struct ppc_inst *inst, struct ppc_inst *src); #endif /* _ASM_POWERPC_INST_H */ diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c index 938db36864dd..bbb4181621dd 100644 --- a/arch/powerpc/kernel/align.c +++ b/arch/powerpc/kernel/align.c @@ -305,7 +305,7 @@ int fix_alignment(struct pt_regs *regs) int r, type; if (is_kernel_addr(regs->nip)) - r = probe_kernel_read_inst(&instr, (void *)regs->nip); + r = copy_inst_from_kernel_nofault(&instr, (void *)regs->nip); else r = __get_user_instr(instr, (void __user *)regs->nip); diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index 42761ebec9f7..ffe9537195aa 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -68,7 +68,7 @@ ftrace_modify_code(unsigned long ip, struct ppc_inst old, struct ppc_inst new) */ /* read the text we want to modify */ - if (probe_kernel_read_inst(&replaced, (void *)ip)) + if (copy_inst_from_kernel_nofault(&replaced, (void *)ip)) return -EFAULT; /* Make sure it is what we expect it to be */ @@ -130,7 +130,7 @@ __ftrace_make_nop(struct module *mod, struct ppc_inst op, pop; /* read where this goes */ - if (probe_kernel_read_inst(&op, (void *)ip)) { + if (copy_inst_from_kernel_nofault(&op, (void *)ip)) { pr_err("Fetching opcode failed.\n"); return -EFAULT; } @@ -164,7 +164,7 @@ __ftrace_make_nop(struct module *mod, /* When using -mkernel_profile there is no load to jump over */ pop = ppc_inst(PPC_INST_NOP); - if (probe_kernel_read_inst(&op, (void *)(ip - 4))) { + if (copy_inst_from_kernel_nofault(&op, (void *)(ip - 4))) { pr_err("Fetching instruction at %lx failed.\n", ip - 4); return -EFAULT; } @@ -197,7 +197,7 @@ __ftrace_make_nop(struct module *mod, * Check what is in the next instruction. We can see ld r2,40(r1), but * on first pass after boot we will see mflr r0. */ - if (probe_kernel_read_inst(&op, (void *)(ip + 4))) { + if (copy_inst_from_kernel_nofault(&op, (void *)(ip + 4))) { pr_err("Fetching op failed.\n"); return -EFAULT; } @@ -349,7 +349,7 @@ static int setup_mcount_compiler_tramp(unsigned long tramp) return -1; /* New trampoline -- read where this goes */ - if (probe_kernel_read_inst(&op, (void *)tramp)) { + if (copy_inst_from_kernel_nofault(&op, (void *)tramp)) { pr_debug("Fetching opcode failed.\n"); return -1; } @@ -399,7 +399,7 @@ static int __ftrace_make_nop_kernel(struct dyn_ftrace *rec, unsigned long addr) struct ppc_inst op; /* Read where this goes */ - if (probe_kernel_read_inst(&op, (void *)ip)) { + if (copy_inst_from_kernel_nofault(&op, (void *)ip)) { pr_err("Fetching opcode failed.\n"); return -EFAULT; } @@ -526,10 +526,10 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) struct module *mod = rec->arch.mod; /* read where this goes */ - if (probe_kernel_read_inst(op, ip)) + if (copy_inst_from_kernel_nofault(op, ip)) return -EFAULT; - if (probe_kernel_read_inst(op + 1, ip + 4)) + if (copy_inst_from_kernel_nofault(op + 1, ip + 4)) return -EFAULT; if (!expected_nop_sequence(ip, op[0], op[1])) { @@ -592,7 +592,7 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) unsigned long ip = rec->ip; /* read where this goes */ - if (probe_kernel_read_inst(&op, (void *)ip)) + if (copy_inst_from_kernel_nofault(&op, (void *)ip)) return -EFAULT; /* It should be pointing to a nop */ @@ -648,7 +648,7 @@ static int __ftrace_make_call_kernel(struct dyn_ftrace *rec, unsigned long addr) } /* Make sure we have a nop */ - if (probe_kernel_read_inst(&op, ip)) { + if (copy_inst_from_kernel_nofault(&op, ip)) { pr_err("Unable to read ftrace location %p\n", ip); return -EFAULT; } @@ -726,7 +726,7 @@ __ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, } /* read where this goes */ - if (probe_kernel_read_inst(&op, (void *)ip)) { + if (copy_inst_from_kernel_nofault(&op, (void *)ip)) { pr_err("Fetching opcode failed.\n"); return -EFAULT; } diff --git a/arch/powerpc/lib/inst.c b/arch/powerpc/lib/inst.c index 0dff3ac2d45f..e554d1357f2f 100644 --- a/arch/powerpc/lib/inst.c +++ b/arch/powerpc/lib/inst.c @@ -8,8 +8,7 @@ #include #include -int probe_kernel_read_inst(struct ppc_inst *inst, - struct ppc_inst *src) +int copy_inst_from_kernel_nofault(struct ppc_inst *inst, struct ppc_inst *src) { unsigned int val, suffix; int err; -- cgit v1.2.3 From 39352430aaa05fbe4ba710231c70b334513078f2 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Wed, 14 Apr 2021 13:08:43 +0000 Subject: powerpc: Move copy_inst_from_kernel_nofault() When probe_kernel_read_inst() was created, there was no good place to put it, so a file called lib/inst.c was dedicated for it. Since then, probe_kernel_read_inst() has been renamed copy_inst_from_kernel_nofault(). And mm/maccess.h didn't exist at that time. Today, mm/maccess.h is related to copy_from_kernel_nofault(). Move copy_inst_from_kernel_nofault() into mm/maccess.c Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/9655d8957313906b77b8db5700a0e33ce06f45e5.1618405715.git.christophe.leroy@csgroup.eu --- arch/powerpc/lib/Makefile | 2 +- arch/powerpc/lib/inst.c | 26 -------------------------- arch/powerpc/mm/maccess.c | 21 +++++++++++++++++++++ 3 files changed, 22 insertions(+), 27 deletions(-) delete mode 100644 arch/powerpc/lib/inst.c (limited to 'arch/powerpc/lib/inst.c') diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile index d4efc182662a..f2c690ee75d1 100644 --- a/arch/powerpc/lib/Makefile +++ b/arch/powerpc/lib/Makefile @@ -16,7 +16,7 @@ CFLAGS_code-patching.o += -DDISABLE_BRANCH_PROFILING CFLAGS_feature-fixups.o += -DDISABLE_BRANCH_PROFILING endif -obj-y += alloc.o code-patching.o feature-fixups.o pmem.o inst.o test_code-patching.o +obj-y += alloc.o code-patching.o feature-fixups.o pmem.o test_code-patching.o ifndef CONFIG_KASAN obj-y += string.o memcmp_$(BITS).o diff --git a/arch/powerpc/lib/inst.c b/arch/powerpc/lib/inst.c deleted file mode 100644 index e554d1357f2f..000000000000 --- a/arch/powerpc/lib/inst.c +++ /dev/null @@ -1,26 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * Copyright 2020, IBM Corporation. - */ - -#include -#include -#include -#include - -int copy_inst_from_kernel_nofault(struct ppc_inst *inst, struct ppc_inst *src) -{ - unsigned int val, suffix; - int err; - - err = copy_from_kernel_nofault(&val, src, sizeof(val)); - if (err) - return err; - if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) { - err = copy_from_kernel_nofault(&suffix, (void *)src + 4, 4); - *inst = ppc_inst_prefix(val, suffix); - } else { - *inst = ppc_inst(val); - } - return err; -} diff --git a/arch/powerpc/mm/maccess.c b/arch/powerpc/mm/maccess.c index fa9a7a718fc6..a3c30a884076 100644 --- a/arch/powerpc/mm/maccess.c +++ b/arch/powerpc/mm/maccess.c @@ -3,7 +3,28 @@ #include #include +#include +#include +#include + bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size) { return is_kernel_addr((unsigned long)unsafe_src); } + +int copy_inst_from_kernel_nofault(struct ppc_inst *inst, struct ppc_inst *src) +{ + unsigned int val, suffix; + int err; + + err = copy_from_kernel_nofault(&val, src, sizeof(val)); + if (err) + return err; + if (IS_ENABLED(CONFIG_PPC64) && get_op(val) == OP_PREFIX) { + err = copy_from_kernel_nofault(&suffix, (void *)src + 4, 4); + *inst = ppc_inst_prefix(val, suffix); + } else { + *inst = ppc_inst(val); + } + return err; +} -- cgit v1.2.3