diff options
Diffstat (limited to 'arch/loongarch')
| -rw-r--r-- | arch/loongarch/include/asm/unwind.h | 29 | ||||
| -rw-r--r-- | arch/loongarch/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/loongarch/kernel/traps.c | 3 | ||||
| -rw-r--r-- | arch/loongarch/kernel/unwind.c | 32 | ||||
| -rw-r--r-- | arch/loongarch/kernel/unwind_guess.c | 52 | ||||
| -rw-r--r-- | arch/loongarch/kernel/unwind_prologue.c | 157 |
6 files changed, 129 insertions, 146 deletions
diff --git a/arch/loongarch/include/asm/unwind.h b/arch/loongarch/include/asm/unwind.h index 834ba6bd15d2..36584b95ef8b 100644 --- a/arch/loongarch/include/asm/unwind.h +++ b/arch/loongarch/include/asm/unwind.h @@ -27,6 +27,8 @@ struct unwind_state { unsigned long sp, pc, ra; }; +bool default_next_frame(struct unwind_state *state); + void unwind_start(struct unwind_state *state, struct task_struct *task, struct pt_regs *regs); bool unwind_next_frame(struct unwind_state *state); @@ -50,4 +52,31 @@ static inline unsigned long unwind_graph_addr(struct unwind_state *state, return ftrace_graph_ret_addr(state->task, &state->graph_idx, pc, (unsigned long *)(cfa - GRAPH_FAKE_OFFSET)); } + +static __always_inline void __unwind_start(struct unwind_state *state, + struct task_struct *task, struct pt_regs *regs) +{ + memset(state, 0, sizeof(*state)); + if (regs) { + state->sp = regs->regs[3]; + state->pc = regs->csr_era; + state->ra = regs->regs[1]; + } else if (task && task != current) { + state->sp = thread_saved_fp(task); + state->pc = thread_saved_ra(task); + state->ra = 0; + } else { + state->sp = (unsigned long)__builtin_frame_address(0); + state->pc = (unsigned long)__builtin_return_address(0); + state->ra = 0; + } + state->task = task; + get_stack_info(state->sp, state->task, &state->stack_info); + state->pc = unwind_graph_addr(state, state->pc, state->sp); +} + +static __always_inline unsigned long __unwind_get_return_address(struct unwind_state *state) +{ + return unwind_done(state) ? 0 : state->pc; +} #endif /* _ASM_UNWIND_H */ diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile index fcaa024a685e..c8cfbd562921 100644 --- a/arch/loongarch/kernel/Makefile +++ b/arch/loongarch/kernel/Makefile @@ -8,7 +8,7 @@ extra-y := vmlinux.lds obj-y += head.o cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \ traps.o irq.o idle.o process.o dma.o mem.o io.o reset.o switch.o \ elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o \ - alternative.o unaligned.o + alternative.o unaligned.o unwind.o obj-$(CONFIG_ACPI) += acpi.o obj-$(CONFIG_EFI) += efi.o diff --git a/arch/loongarch/kernel/traps.c b/arch/loongarch/kernel/traps.c index 7ea62faeeadb..c38a146a973b 100644 --- a/arch/loongarch/kernel/traps.c +++ b/arch/loongarch/kernel/traps.c @@ -72,9 +72,6 @@ static void show_backtrace(struct task_struct *task, const struct pt_regs *regs, if (!task) task = current; - if (user_mode(regs)) - state.type = UNWINDER_GUESS; - printk("%sCall Trace:", loglvl); for (unwind_start(&state, task, pregs); !unwind_done(&state); unwind_next_frame(&state)) { diff --git a/arch/loongarch/kernel/unwind.c b/arch/loongarch/kernel/unwind.c new file mode 100644 index 000000000000..a463d6961344 --- /dev/null +++ b/arch/loongarch/kernel/unwind.c @@ -0,0 +1,32 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2022-2023 Loongson Technology Corporation Limited + */ +#include <linux/kernel.h> +#include <linux/ftrace.h> + +#include <asm/unwind.h> + +bool default_next_frame(struct unwind_state *state) +{ + struct stack_info *info = &state->stack_info; + unsigned long addr; + + if (unwind_done(state)) + return false; + + do { + for (state->sp += sizeof(unsigned long); + state->sp < info->end; state->sp += sizeof(unsigned long)) { + addr = *(unsigned long *)(state->sp); + state->pc = unwind_graph_addr(state, addr, state->sp + 8); + if (__kernel_text_address(state->pc)) + return true; + } + + state->sp = info->next_sp; + + } while (!get_stack_info(state->sp, state->task, info)); + + return false; +} diff --git a/arch/loongarch/kernel/unwind_guess.c b/arch/loongarch/kernel/unwind_guess.c index e7e637bdba17..98379b7d4147 100644 --- a/arch/loongarch/kernel/unwind_guess.c +++ b/arch/loongarch/kernel/unwind_guess.c @@ -2,41 +2,18 @@ /* * Copyright (C) 2022 Loongson Technology Corporation Limited */ -#include <linux/kernel.h> -#include <linux/ftrace.h> - #include <asm/unwind.h> unsigned long unwind_get_return_address(struct unwind_state *state) { - if (unwind_done(state)) - return 0; - - return state->pc; + return __unwind_get_return_address(state); } EXPORT_SYMBOL_GPL(unwind_get_return_address); void unwind_start(struct unwind_state *state, struct task_struct *task, struct pt_regs *regs) { - memset(state, 0, sizeof(*state)); - - if (regs) { - state->sp = regs->regs[3]; - state->pc = regs->csr_era; - } else if (task && task != current) { - state->sp = thread_saved_fp(task); - state->pc = thread_saved_ra(task); - } else { - state->sp = (unsigned long)__builtin_frame_address(0); - state->pc = (unsigned long)__builtin_return_address(0); - } - - state->task = task; - state->first = true; - state->pc = unwind_graph_addr(state, state->pc, state->sp); - get_stack_info(state->sp, state->task, &state->stack_info); - + __unwind_start(state, task, regs); if (!unwind_done(state) && !__kernel_text_address(state->pc)) unwind_next_frame(state); } @@ -44,29 +21,6 @@ EXPORT_SYMBOL_GPL(unwind_start); bool unwind_next_frame(struct unwind_state *state) { - struct stack_info *info = &state->stack_info; - unsigned long addr; - - if (unwind_done(state)) - return false; - - if (state->first) - state->first = false; - - do { - for (state->sp += sizeof(unsigned long); - state->sp < info->end; - state->sp += sizeof(unsigned long)) { - addr = *(unsigned long *)(state->sp); - state->pc = unwind_graph_addr(state, addr, state->sp + 8); - if (__kernel_text_address(state->pc)) - return true; - } - - state->sp = info->next_sp; - - } while (!get_stack_info(state->sp, state->task, info)); - - return false; + return default_next_frame(state); } EXPORT_SYMBOL_GPL(unwind_next_frame); diff --git a/arch/loongarch/kernel/unwind_prologue.c b/arch/loongarch/kernel/unwind_prologue.c index 463ba2391bdf..dfc352dba746 100644 --- a/arch/loongarch/kernel/unwind_prologue.c +++ b/arch/loongarch/kernel/unwind_prologue.c @@ -19,32 +19,14 @@ static inline void unwind_state_fixup(struct unwind_state *state) #endif } -unsigned long unwind_get_return_address(struct unwind_state *state) -{ - if (unwind_done(state)) - return 0; - - return state->pc; -} -EXPORT_SYMBOL_GPL(unwind_get_return_address); - -static bool unwind_by_guess(struct unwind_state *state) -{ - struct stack_info *info = &state->stack_info; - unsigned long addr; - - for (state->sp += sizeof(unsigned long); - state->sp < info->end; - state->sp += sizeof(unsigned long)) { - addr = *(unsigned long *)(state->sp); - state->pc = unwind_graph_addr(state, addr, state->sp + 8); - if (__kernel_text_address(state->pc)) - return true; - } - - return false; -} - +/* + * LoongArch function prologue is like follows, + * [instructions not use stack var] + * addi.d sp, sp, -imm + * st.d xx, sp, offset <- save callee saved regs and + * st.d yy, sp, offset save ra if function is nest. + * [others instructions] + */ static bool unwind_by_prologue(struct unwind_state *state) { long frame_ra = -1; @@ -91,6 +73,10 @@ static bool unwind_by_prologue(struct unwind_state *state) ip++; } + /* + * Can't find stack alloc action, PC may be in a leaf function. Only the + * first being true is reasonable, otherwise indicate analysis is broken. + */ if (!frame_size) { if (state->first) goto first; @@ -108,6 +94,7 @@ static bool unwind_by_prologue(struct unwind_state *state) ip++; } + /* Can't find save $ra action, PC may be in a leaf function, too. */ if (frame_ra < 0) { if (state->first) { state->sp = state->sp + frame_size; @@ -116,96 +103,48 @@ static bool unwind_by_prologue(struct unwind_state *state) return false; } - if (state->first) - state->first = false; - state->pc = *(unsigned long *)(state->sp + frame_ra); state->sp = state->sp + frame_size; goto out; first: - state->first = false; - if (state->pc == state->ra) - return false; - state->pc = state->ra; out: + state->first = false; unwind_state_fixup(state); return !!__kernel_text_address(state->pc); } -void unwind_start(struct unwind_state *state, struct task_struct *task, - struct pt_regs *regs) -{ - memset(state, 0, sizeof(*state)); - state->type = UNWINDER_PROLOGUE; - - if (regs) { - state->sp = regs->regs[3]; - state->pc = regs->csr_era; - state->ra = regs->regs[1]; - if (!__kernel_text_address(state->pc)) - state->type = UNWINDER_GUESS; - } else if (task && task != current) { - state->sp = thread_saved_fp(task); - state->pc = thread_saved_ra(task); - state->ra = 0; - } else { - state->sp = (unsigned long)__builtin_frame_address(0); - state->pc = (unsigned long)__builtin_return_address(0); - state->ra = 0; - } - - state->task = task; - state->first = true; - state->pc = unwind_graph_addr(state, state->pc, state->sp); - get_stack_info(state->sp, state->task, &state->stack_info); - - if (!unwind_done(state) && !__kernel_text_address(state->pc)) - unwind_next_frame(state); -} -EXPORT_SYMBOL_GPL(unwind_start); - -bool unwind_next_frame(struct unwind_state *state) +static bool next_frame(struct unwind_state *state) { - struct stack_info *info = &state->stack_info; - struct pt_regs *regs; unsigned long pc; + struct pt_regs *regs; + struct stack_info *info = &state->stack_info; if (unwind_done(state)) return false; do { - switch (state->type) { - case UNWINDER_GUESS: - state->first = false; - if (unwind_by_guess(state)) - return true; - break; - - case UNWINDER_PROLOGUE: - if (unwind_by_prologue(state)) { - state->pc = unwind_graph_addr(state, state->pc, state->sp); - return true; - } + if (unwind_by_prologue(state)) { + state->pc = unwind_graph_addr(state, state->pc, state->sp); + return true; + } - if (info->type == STACK_TYPE_IRQ && - info->end == state->sp) { - regs = (struct pt_regs *)info->next_sp; - pc = regs->csr_era; + if (info->type == STACK_TYPE_IRQ && info->end == state->sp) { + regs = (struct pt_regs *)info->next_sp; + pc = regs->csr_era; - if (user_mode(regs) || !__kernel_text_address(pc)) - return false; + if (user_mode(regs) || !__kernel_text_address(pc)) + return false; - state->first = true; - state->ra = regs->regs[1]; - state->sp = regs->regs[3]; - state->pc = pc; - get_stack_info(state->sp, state->task, info); + state->first = true; + state->pc = pc; + state->ra = regs->regs[1]; + state->sp = regs->regs[3]; + get_stack_info(state->sp, state->task, info); - return true; - } + return true; } state->sp = info->next_sp; @@ -214,4 +153,36 @@ bool unwind_next_frame(struct unwind_state *state) return false; } + +unsigned long unwind_get_return_address(struct unwind_state *state) +{ + return __unwind_get_return_address(state); +} +EXPORT_SYMBOL_GPL(unwind_get_return_address); + +void unwind_start(struct unwind_state *state, struct task_struct *task, + struct pt_regs *regs) +{ + __unwind_start(state, task, regs); + state->type = UNWINDER_PROLOGUE; + state->first = true; + + /* + * The current PC is not kernel text address, we cannot find its + * relative symbol. Thus, prologue analysis will be broken. Luckily, + * we can use the default_next_frame(). + */ + if (!__kernel_text_address(state->pc)) { + state->type = UNWINDER_GUESS; + if (!unwind_done(state)) + unwind_next_frame(state); + } +} +EXPORT_SYMBOL_GPL(unwind_start); + +bool unwind_next_frame(struct unwind_state *state) +{ + return state->type == UNWINDER_PROLOGUE ? + next_frame(state) : default_next_frame(state); +} EXPORT_SYMBOL_GPL(unwind_next_frame); |