From 7888af4166d4ab07ba51234be6ba332b7807e901 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 8 Oct 2024 19:05:28 -0400 Subject: ftrace: Make ftrace_regs abstract from direct use ftrace_regs was created to hold registers that store information to save function parameters, return value and stack. Since it is a subset of pt_regs, it should only be used by its accessor functions. But because pt_regs can easily be taken from ftrace_regs (on most archs), it is tempting to use it directly. But when running on other architectures, it may fail to build or worse, build but crash the kernel! Instead, make struct ftrace_regs an empty structure and have the architectures define __arch_ftrace_regs and all the accessor functions will typecast to it to get to the actual fields. This will help avoid usage of ftrace_regs directly. Link: https://lore.kernel.org/all/20241007171027.629bdafd@gandalf.local.home/ Cc: "linux-arch@vger.kernel.org" Cc: "x86@kernel.org" Cc: Mathieu Desnoyers Cc: Mark Rutland Cc: Will Deacon Cc: Huacai Chen Cc: WANG Xuerui Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: Naveen N Rao Cc: Madhavan Srinivasan Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Sven Schnelle Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Link: https://lore.kernel.org/20241008230628.958778821@goodmis.org Acked-by: Catalin Marinas Signed-off-by: Steven Rostedt (Google) Acked-by: Masami Hiramatsu (Google) Acked-by: Heiko Carstens # s390 Signed-off-by: Steven Rostedt (Google) --- arch/powerpc/include/asm/ftrace.h | 21 ++++++++++++--------- arch/powerpc/kernel/trace/ftrace.c | 4 ++-- arch/powerpc/kernel/trace/ftrace_64_pg.c | 2 +- 3 files changed, 15 insertions(+), 12 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index 559560286e6d..e299fd47d201 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -32,39 +32,42 @@ struct dyn_arch_ftrace { int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); #define ftrace_init_nop ftrace_init_nop -struct ftrace_regs { +struct ftrace_regs; +#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) + +struct __arch_ftrace_regs { struct pt_regs regs; }; static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) { /* We clear regs.msr in ftrace_call */ - return fregs->regs.msr ? &fregs->regs : NULL; + return arch_ftrace_regs(fregs)->regs.msr ? &arch_ftrace_regs(fregs)->regs : NULL; } static __always_inline void ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) { - regs_set_return_ip(&fregs->regs, ip); + regs_set_return_ip(&arch_ftrace_regs(fregs)->regs, ip); } static __always_inline unsigned long ftrace_regs_get_instruction_pointer(struct ftrace_regs *fregs) { - return instruction_pointer(&fregs->regs); + return instruction_pointer(&arch_ftrace_regs(fregs)->regs); } #define ftrace_regs_get_argument(fregs, n) \ - regs_get_kernel_argument(&(fregs)->regs, n) + regs_get_kernel_argument(&arch_ftrace_regs(fregs)->regs, n) #define ftrace_regs_get_stack_pointer(fregs) \ - kernel_stack_pointer(&(fregs)->regs) + kernel_stack_pointer(&arch_ftrace_regs(fregs)->regs) #define ftrace_regs_return_value(fregs) \ - regs_return_value(&(fregs)->regs) + regs_return_value(&arch_ftrace_regs(fregs)->regs) #define ftrace_regs_set_return_value(fregs, ret) \ - regs_set_return_value(&(fregs)->regs, ret) + regs_set_return_value(&arch_ftrace_regs(fregs)->regs, ret) #define ftrace_override_function_with_return(fregs) \ - override_function_with_return(&(fregs)->regs) + override_function_with_return(&arch_ftrace_regs(fregs)->regs) #define ftrace_regs_query_register_offset(name) \ regs_query_register_offset(name) diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c index d8d6b4fd9a14..df41f4a7c738 100644 --- a/arch/powerpc/kernel/trace/ftrace.c +++ b/arch/powerpc/kernel/trace/ftrace.c @@ -421,7 +421,7 @@ int __init ftrace_dyn_arch_init(void) void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { - unsigned long sp = fregs->regs.gpr[1]; + unsigned long sp = arch_ftrace_regs(fregs)->regs.gpr[1]; int bit; if (unlikely(ftrace_graph_is_dead())) @@ -439,6 +439,6 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, ftrace_test_recursion_unlock(bit); out: - fregs->regs.link = parent_ip; + arch_ftrace_regs(fregs)->regs.link = parent_ip; } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.c b/arch/powerpc/kernel/trace/ftrace_64_pg.c index 12fab1803bcf..d3c5552e4984 100644 --- a/arch/powerpc/kernel/trace/ftrace_64_pg.c +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c @@ -829,7 +829,7 @@ out: void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs) { - fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]); + arch_ftrace_regs(fregs)->regs.link = __prepare_ftrace_return(parent_ip, ip, arch_ftrace_regs(fregs)->regs.gpr[1]); } #else unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip, -- cgit v1.2.3 From e4cf33ca48128d580e25ebe779b7ba7b4b4cf733 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Thu, 10 Oct 2024 20:21:14 -0400 Subject: ftrace: Consolidate ftrace_regs accessor functions for archs using pt_regs Most architectures use pt_regs within ftrace_regs making a lot of the accessor functions just calls to the pt_regs internally. Instead of duplication this effort, use a HAVE_ARCH_FTRACE_REGS for architectures that have their own ftrace_regs that is not based on pt_regs and will define all the accessor functions, and for the architectures that just use pt_regs, it will leave it undefined, and the default accessor functions will be used. Note, this will also make it easier to add new accessor functions to ftrace_regs as it will mean having to touch less architectures. Cc: Cc: "x86@kernel.org" Cc: Mathieu Desnoyers Cc: Mark Rutland Cc: Will Deacon Cc: Huacai Chen Cc: WANG Xuerui Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: Naveen N Rao Cc: Madhavan Srinivasan Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Alexander Gordeev Cc: Christian Borntraeger Cc: Sven Schnelle Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Link: https://lore.kernel.org/20241010202114.2289f6fd@gandalf.local.home Acked-by: Masami Hiramatsu (Google) Acked-by: Heiko Carstens # s390 Acked-by: Catalin Marinas Acked-by: Michael Ellerman # powerpc Suggested-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- arch/arm64/include/asm/ftrace.h | 1 + arch/loongarch/include/asm/ftrace.h | 25 +------------------------ arch/powerpc/include/asm/ftrace.h | 26 +------------------------- arch/riscv/include/asm/ftrace.h | 1 + arch/s390/include/asm/ftrace.h | 26 +------------------------- arch/x86/include/asm/ftrace.h | 21 +-------------------- include/linux/ftrace.h | 32 +++++++------------------------- include/linux/ftrace_regs.h | 36 ++++++++++++++++++++++++++++++++++++ 8 files changed, 49 insertions(+), 119 deletions(-) create mode 100644 include/linux/ftrace_regs.h (limited to 'arch/powerpc') diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index bbb69c7751b9..5ccff4de7f09 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -54,6 +54,7 @@ extern void return_to_handler(void); unsigned long ftrace_call_adjust(unsigned long addr); #ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS +#define HAVE_ARCH_FTRACE_REGS struct dyn_ftrace; struct ftrace_ops; struct ftrace_regs; diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h index 0e15d36ce251..8f13eaeaa325 100644 --- a/arch/loongarch/include/asm/ftrace.h +++ b/arch/loongarch/include/asm/ftrace.h @@ -43,43 +43,20 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent); #ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS struct ftrace_ops; -struct ftrace_regs; -#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) -struct __arch_ftrace_regs { - struct pt_regs regs; -}; +#include static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) { return &arch_ftrace_regs(fregs)->regs; } -static __always_inline unsigned long -ftrace_regs_get_instruction_pointer(struct ftrace_regs *fregs) -{ - return instruction_pointer(&arch_ftrace_regs(fregs)->regs); -} - static __always_inline void ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) { instruction_pointer_set(&arch_ftrace_regs(fregs)->regs, ip); } -#define ftrace_regs_get_argument(fregs, n) \ - regs_get_kernel_argument(&arch_ftrace_regs(fregs)->regs, n) -#define ftrace_regs_get_stack_pointer(fregs) \ - kernel_stack_pointer(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ - regs_return_value(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_set_return_value(fregs, ret) \ - regs_set_return_value(&arch_ftrace_regs(fregs)->regs, ret) -#define ftrace_override_function_with_return(fregs) \ - override_function_with_return(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_query_register_offset(name) \ - regs_query_register_offset(name) - #define ftrace_graph_func ftrace_graph_func void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index e299fd47d201..0edfb874eb02 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -32,12 +32,7 @@ struct dyn_arch_ftrace { int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); #define ftrace_init_nop ftrace_init_nop -struct ftrace_regs; -#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) - -struct __arch_ftrace_regs { - struct pt_regs regs; -}; +#include static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) { @@ -52,25 +47,6 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, regs_set_return_ip(&arch_ftrace_regs(fregs)->regs, ip); } -static __always_inline unsigned long -ftrace_regs_get_instruction_pointer(struct ftrace_regs *fregs) -{ - return instruction_pointer(&arch_ftrace_regs(fregs)->regs); -} - -#define ftrace_regs_get_argument(fregs, n) \ - regs_get_kernel_argument(&arch_ftrace_regs(fregs)->regs, n) -#define ftrace_regs_get_stack_pointer(fregs) \ - kernel_stack_pointer(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ - regs_return_value(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_set_return_value(fregs, ret) \ - regs_set_return_value(&arch_ftrace_regs(fregs)->regs, ret) -#define ftrace_override_function_with_return(fregs) \ - override_function_with_return(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_query_register_offset(name) \ - regs_query_register_offset(name) - struct ftrace_ops; #define ftrace_graph_func ftrace_graph_func diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index c6bcdff105b5..3d66437a1029 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -125,6 +125,7 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); #ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS #define arch_ftrace_get_regs(regs) NULL +#define HAVE_ARCH_FTRACE_REGS struct ftrace_ops; struct ftrace_regs; #define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 1498d0a9c762..fc97d75dc752 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -51,12 +51,7 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) return addr; } -struct ftrace_regs; -#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) - -struct __arch_ftrace_regs { - struct pt_regs regs; -}; +#include static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) { @@ -84,12 +79,6 @@ static __always_inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -static __always_inline unsigned long -ftrace_regs_get_instruction_pointer(const struct ftrace_regs *fregs) -{ - return arch_ftrace_regs(fregs)->regs.psw.addr; -} - static __always_inline void ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) @@ -97,19 +86,6 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, arch_ftrace_regs(fregs)->regs.psw.addr = ip; } -#define ftrace_regs_get_argument(fregs, n) \ - regs_get_kernel_argument(&arch_ftrace_regs(fregs)->regs, n) -#define ftrace_regs_get_stack_pointer(fregs) \ - kernel_stack_pointer(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ - regs_return_value(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_set_return_value(fregs, ret) \ - regs_set_return_value(&arch_ftrace_regs(fregs)->regs, ret) -#define ftrace_override_function_with_return(fregs) \ - override_function_with_return(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_query_register_offset(name) \ - regs_query_register_offset(name) - #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS /* * When an ftrace registered caller is tracing a function that is diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 87943f7a299b..8f02d28c571a 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -33,12 +33,8 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr) } #ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS -struct ftrace_regs; -#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) -struct __arch_ftrace_regs { - struct pt_regs regs; -}; +#include static __always_inline struct pt_regs * arch_ftrace_get_regs(struct ftrace_regs *fregs) @@ -52,21 +48,6 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) #define ftrace_regs_set_instruction_pointer(fregs, _ip) \ do { arch_ftrace_regs(fregs)->regs.ip = (_ip); } while (0) -#define ftrace_regs_get_instruction_pointer(fregs) \ - arch_ftrace_regs(fregs)->regs.ip) - -#define ftrace_regs_get_argument(fregs, n) \ - regs_get_kernel_argument(&arch_ftrace_regs(fregs)->regs, n) -#define ftrace_regs_get_stack_pointer(fregs) \ - kernel_stack_pointer(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_return_value(fregs) \ - regs_return_value(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_set_return_value(fregs, ret) \ - regs_set_return_value(&arch_ftrace_regs(fregs)->regs, ret) -#define ftrace_override_function_with_return(fregs) \ - override_function_with_return(&arch_ftrace_regs(fregs)->regs) -#define ftrace_regs_query_register_offset(name) \ - regs_query_register_offset(name) struct ftrace_ops; #define ftrace_graph_func ftrace_graph_func diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 66f10291a0b2..aa9ddd1e4bb6 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -113,6 +113,8 @@ static inline int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *val #ifdef CONFIG_FUNCTION_TRACER +#include + extern int ftrace_enabled; /** @@ -150,14 +152,11 @@ struct ftrace_regs { #define ftrace_regs_size() sizeof(struct __arch_ftrace_regs) #ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS - -struct __arch_ftrace_regs { - struct pt_regs regs; -}; - -struct ftrace_regs; -#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) - +/* + * Architectures that define HAVE_DYNAMIC_FTRACE_WITH_ARGS must define their own + * arch_ftrace_get_regs() where it only returns pt_regs *if* it is fully + * populated. It should return NULL otherwise. + */ static inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *fregs) { return &arch_ftrace_regs(fregs)->regs; @@ -191,23 +190,6 @@ static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs) return ftrace_get_regs(fregs) != NULL; } -#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS -#define ftrace_regs_get_instruction_pointer(fregs) \ - instruction_pointer(ftrace_get_regs(fregs)) -#define ftrace_regs_get_argument(fregs, n) \ - regs_get_kernel_argument(ftrace_get_regs(fregs), n) -#define ftrace_regs_get_stack_pointer(fregs) \ - kernel_stack_pointer(ftrace_get_regs(fregs)) -#define ftrace_regs_return_value(fregs) \ - regs_return_value(ftrace_get_regs(fregs)) -#define ftrace_regs_set_return_value(fregs, ret) \ - regs_set_return_value(ftrace_get_regs(fregs), ret) -#define ftrace_override_function_with_return(fregs) \ - override_function_with_return(ftrace_get_regs(fregs)) -#define ftrace_regs_query_register_offset(name) \ - regs_query_register_offset(name) -#endif - typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); diff --git a/include/linux/ftrace_regs.h b/include/linux/ftrace_regs.h new file mode 100644 index 000000000000..dea6a0851b74 --- /dev/null +++ b/include/linux/ftrace_regs.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_FTRACE_REGS_H +#define _LINUX_FTRACE_REGS_H + +/* + * For archs that just copy pt_regs in ftrace regs, it can use this default. + * If an architecture does not use pt_regs, it must define all the below + * accessor functions. + */ +#ifndef HAVE_ARCH_FTRACE_REGS +struct __arch_ftrace_regs { + struct pt_regs regs; +}; + +#define arch_ftrace_regs(fregs) ((struct __arch_ftrace_regs *)(fregs)) + +struct ftrace_regs; + +#define ftrace_regs_get_instruction_pointer(fregs) \ + instruction_pointer(arch_ftrace_get_regs(fregs)) +#define ftrace_regs_get_argument(fregs, n) \ + regs_get_kernel_argument(arch_ftrace_get_regs(fregs), n) +#define ftrace_regs_get_stack_pointer(fregs) \ + kernel_stack_pointer(arch_ftrace_get_regs(fregs)) +#define ftrace_regs_return_value(fregs) \ + regs_return_value(arch_ftrace_get_regs(fregs)) +#define ftrace_regs_set_return_value(fregs, ret) \ + regs_set_return_value(arch_ftrace_get_regs(fregs), ret) +#define ftrace_override_function_with_return(fregs) \ + override_function_with_return(arch_ftrace_get_regs(fregs)) +#define ftrace_regs_query_register_offset(name) \ + regs_query_register_offset(name) + +#endif /* HAVE_ARCH_FTRACE_REGS */ + +#endif /* _LINUX_FTRACE_REGS_H */ -- cgit v1.2.3