diff options
| -rw-r--r-- | include/linux/ftrace.h | 9 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 37 |
2 files changed, 45 insertions, 1 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index eae6548efbf0..870c8eea38cd 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -296,6 +296,15 @@ int ftrace_arch_code_modify_post_process(void); struct dyn_ftrace; +enum ftrace_bug_type { + FTRACE_BUG_UNKNOWN, + FTRACE_BUG_INIT, + FTRACE_BUG_NOP, + FTRACE_BUG_CALL, + FTRACE_BUG_UPDATE, +}; +extern enum ftrace_bug_type ftrace_bug_type; + void ftrace_bug(int err, struct dyn_ftrace *rec); struct seq_file; diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 3f743b147247..b95efcac9dfe 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1953,6 +1953,28 @@ static void print_ip_ins(const char *fmt, unsigned char *p) static struct ftrace_ops * ftrace_find_tramp_ops_any(struct dyn_ftrace *rec); +enum ftrace_bug_type ftrace_bug_type; + +static void print_bug_type(void) +{ + switch (ftrace_bug_type) { + case FTRACE_BUG_UNKNOWN: + break; + case FTRACE_BUG_INIT: + pr_info("Initializing ftrace call sites\n"); + break; + case FTRACE_BUG_NOP: + pr_info("Setting ftrace call site to NOP\n"); + break; + case FTRACE_BUG_CALL: + pr_info("Setting ftrace call site to call ftrace function\n"); + break; + case FTRACE_BUG_UPDATE: + pr_info("Updating ftrace call site to call a different ftrace function\n"); + break; + } +} + /** * ftrace_bug - report and shutdown function tracer * @failed: The failed type (EFAULT, EINVAL, EPERM) @@ -1992,6 +2014,7 @@ void ftrace_bug(int failed, struct dyn_ftrace *rec) pr_info("ftrace faulted on unknown error "); print_ip_sym(ip); } + print_bug_type(); if (rec) { struct ftrace_ops *ops = NULL; @@ -2016,6 +2039,8 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) { unsigned long flag = 0UL; + ftrace_bug_type = FTRACE_BUG_UNKNOWN; + /* * If we are updating calls: * @@ -2077,9 +2102,12 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) * from the save regs, to a non-save regs function or * vice versa, or from a trampoline call. */ - if (flag & FTRACE_FL_ENABLED) + if (flag & FTRACE_FL_ENABLED) { + ftrace_bug_type = FTRACE_BUG_CALL; return FTRACE_UPDATE_MAKE_CALL; + } + ftrace_bug_type = FTRACE_BUG_UPDATE; return FTRACE_UPDATE_MODIFY_CALL; } @@ -2096,6 +2124,7 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update) FTRACE_FL_REGS_EN); } + ftrace_bug_type = FTRACE_BUG_NOP; return FTRACE_UPDATE_MAKE_NOP; } @@ -2307,17 +2336,22 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable) ret = ftrace_update_record(rec, enable); + ftrace_bug_type = FTRACE_BUG_UNKNOWN; + switch (ret) { case FTRACE_UPDATE_IGNORE: return 0; case FTRACE_UPDATE_MAKE_CALL: + ftrace_bug_type = FTRACE_BUG_CALL; return ftrace_make_call(rec, ftrace_addr); case FTRACE_UPDATE_MAKE_NOP: + ftrace_bug_type = FTRACE_BUG_NOP; return ftrace_make_nop(NULL, rec, ftrace_old_addr); case FTRACE_UPDATE_MODIFY_CALL: + ftrace_bug_type = FTRACE_BUG_UPDATE; return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr); } @@ -2425,6 +2459,7 @@ ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec) ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR); if (ret) { + ftrace_bug_type = FTRACE_BUG_INIT; ftrace_bug(ret, rec); return 0; } |