diff options
Diffstat (limited to 'arch/x86/kernel/unwind_orc.c')
| -rw-r--r-- | arch/x86/kernel/unwind_orc.c | 86 |
1 files changed, 56 insertions, 30 deletions
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c index 3ac50b7298d1..977ee75e047c 100644 --- a/arch/x86/kernel/unwind_orc.c +++ b/arch/x86/kernel/unwind_orc.c @@ -7,14 +7,23 @@ #include <asm/unwind.h> #include <asm/orc_types.h> #include <asm/orc_lookup.h> +#include <asm/orc_header.h> + +ORC_HEADER; #define orc_warn(fmt, ...) \ printk_deferred_once(KERN_WARNING "WARNING: " fmt, ##__VA_ARGS__) #define orc_warn_current(args...) \ ({ \ - if (state->task == current && !state->error) \ + static bool dumped_before; \ + if (state->task == current && !state->error) { \ orc_warn(args); \ + if (unwind_debug && !dumped_before) { \ + dumped_before = true; \ + unwind_dump(state); \ + } \ + } \ }) extern int __start_orc_unwind_ip[]; @@ -23,8 +32,49 @@ extern struct orc_entry __start_orc_unwind[]; extern struct orc_entry __stop_orc_unwind[]; static bool orc_init __ro_after_init; +static bool unwind_debug __ro_after_init; static unsigned int lookup_num_blocks __ro_after_init; +static int __init unwind_debug_cmdline(char *str) +{ + unwind_debug = true; + + return 0; +} +early_param("unwind_debug", unwind_debug_cmdline); + +static void unwind_dump(struct unwind_state *state) +{ + static bool dumped_before; + unsigned long word, *sp; + struct stack_info stack_info = {0}; + unsigned long visit_mask = 0; + + if (dumped_before) + return; + + dumped_before = true; + + printk_deferred("unwind stack type:%d next_sp:%p mask:0x%lx graph_idx:%d\n", + state->stack_info.type, state->stack_info.next_sp, + state->stack_mask, state->graph_idx); + + for (sp = __builtin_frame_address(0); sp; + sp = PTR_ALIGN(stack_info.next_sp, sizeof(long))) { + if (get_stack_info(sp, state->task, &stack_info, &visit_mask)) + break; + + for (; sp < stack_info.end; sp++) { + + word = READ_ONCE_NOCHECK(*sp); + + printk_deferred("%0*lx: %0*lx (%pB)\n", BITS_PER_LONG/4, + (unsigned long)sp, BITS_PER_LONG/4, + word, (void *)word); + } + } +} + static inline unsigned long orc_ip(const int *ip) { return (unsigned long)ip + *ip; @@ -35,7 +85,7 @@ static struct orc_entry *__orc_find(int *ip_table, struct orc_entry *u_table, { int *first = ip_table; int *last = ip_table + num_entries - 1; - int *mid = first, *found = first; + int *mid, *found = first; if (!num_entries) return NULL; @@ -136,21 +186,6 @@ static struct orc_entry null_orc_entry = { .type = ORC_TYPE_CALL }; -#ifdef CONFIG_CALL_THUNKS -static struct orc_entry *orc_callthunk_find(unsigned long ip) -{ - if (!is_callthunk((void *)ip)) - return NULL; - - return &null_orc_entry; -} -#else -static struct orc_entry *orc_callthunk_find(unsigned long ip) -{ - return NULL; -} -#endif - /* Fake frame pointer entry -- used as a fallback for generated code */ static struct orc_entry orc_fp_entry = { .type = ORC_TYPE_CALL, @@ -203,11 +238,7 @@ static struct orc_entry *orc_find(unsigned long ip) if (orc) return orc; - orc = orc_ftrace_find(ip); - if (orc) - return orc; - - return orc_callthunk_find(ip); + return orc_ftrace_find(ip); } #ifdef CONFIG_MODULES @@ -219,7 +250,6 @@ static struct orc_entry *cur_orc_table = __start_orc_unwind; static void orc_sort_swap(void *_a, void *_b, int size) { struct orc_entry *orc_a, *orc_b; - struct orc_entry orc_tmp; int *a = _a, *b = _b, tmp; int delta = _b - _a; @@ -231,9 +261,7 @@ static void orc_sort_swap(void *_a, void *_b, int size) /* Swap the corresponding .orc_unwind entries: */ orc_a = cur_orc_table + (a - cur_orc_ip_table); orc_b = cur_orc_table + (b - cur_orc_ip_table); - orc_tmp = *orc_a; - *orc_a = *orc_b; - *orc_b = orc_tmp; + swap(*orc_a, *orc_b); } static int orc_sort_cmp(const void *_a, const void *_b) @@ -448,7 +476,7 @@ bool unwind_next_frame(struct unwind_state *state) return false; /* Don't let modules unload while we're reading their ORC data. */ - preempt_disable(); + guard(rcu)(); /* End-of-stack check for user tasks: */ if (state->regs && user_mode(state->regs)) @@ -641,14 +669,12 @@ bool unwind_next_frame(struct unwind_state *state) goto err; } - preempt_enable(); return true; err: state->error = true; the_end: - preempt_enable(); state->stack_info.type = STACK_TYPE_UNKNOWN; return false; } @@ -695,7 +721,7 @@ void __unwind_start(struct unwind_state *state, struct task_struct *task, state->sp = task->thread.sp + sizeof(*frame); state->bp = READ_ONCE_NOCHECK(frame->bp); state->ip = READ_ONCE_NOCHECK(frame->ret_addr); - state->signal = (void *)state->ip == ret_from_fork; + state->signal = (void *)state->ip == ret_from_fork_asm; } if (get_stack_info((unsigned long *)state->sp, state->task, |