| Message ID | 20250109174639.32e6f43a@gandalf.local.home (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | ftrace: Implement :mod: cache filtering on kernel command line | expand |
Hi Steven,
kernel test robot noticed the following build warnings:
[auto build test WARNING on linus/master]
[also build test WARNING on v6.13-rc6 next-20250110]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Steven-Rostedt/ftrace-Implement-mod-cache-filtering-on-kernel-command-line/20250110-064649
base: linus/master
patch link: https://lore.kernel.org/r/20250109174639.32e6f43a%40gandalf.local.home
patch subject: [PATCH] ftrace: Implement :mod: cache filtering on kernel command line
config: i386-randconfig-012-20250111 (https://download.01.org/0day-ci/archive/20250111/202501110319.xY9ltUxL-lkp@intel.com/config)
compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250111/202501110319.xY9ltUxL-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202501110319.xY9ltUxL-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> kernel/trace/trace.c:10664:28: warning: no previous prototype for function 'trace_get_global_array' [-Wmissing-prototypes]
10664 | __init struct trace_array *trace_get_global_array(void)
| ^
kernel/trace/trace.c:10664:8: note: declare 'static' if the function is not intended to be used outside of this translation unit
10664 | __init struct trace_array *trace_get_global_array(void)
| ^
| static
1 warning generated.
vim +/trace_get_global_array +10664 kernel/trace/trace.c
10662
10663 /* Used to set module cached ftrace filtering at boot up */
10664 __init struct trace_array *trace_get_global_array(void)
10665 {
10666 return &global_trace;
10667 }
10668
Hi Steven, kernel test robot noticed the following build warnings: [auto build test WARNING on linus/master] [also build test WARNING on v6.13-rc6 next-20250110] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Steven-Rostedt/ftrace-Implement-mod-cache-filtering-on-kernel-command-line/20250110-064649 base: linus/master patch link: https://lore.kernel.org/r/20250109174639.32e6f43a%40gandalf.local.home patch subject: [PATCH] ftrace: Implement :mod: cache filtering on kernel command line config: i386-randconfig-013-20250111 (https://download.01.org/0day-ci/archive/20250111/202501110314.8tTxSS0N-lkp@intel.com/config) compiler: clang version 19.1.3 (https://github.com/llvm/llvm-project ab51eccf88f5321e7c60591c5546b254b6afab99) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250111/202501110314.8tTxSS0N-lkp@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202501110314.8tTxSS0N-lkp@intel.com/ All warnings (new ones prefixed by >>): >> kernel/trace/ftrace.c:6232:6: warning: variable 'mod' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] 6232 | if (next) { | ^~~~ kernel/trace/ftrace.c:6246:67: note: uninitialized use occurs here 6246 | ret = ftrace_set_hash(ops, func, len, NULL, 0, 0, reset, enable, mod); | ^~~ kernel/trace/ftrace.c:6232:2: note: remove the 'if' if its condition is always true 6232 | if (next) { | ^~~~~~~~~ kernel/trace/ftrace.c:6224:11: note: initialize the variable 'mod' to silence this warning 6224 | char *mod, *func, *command, *next = buf; | ^ | = NULL 1 warning generated. vim +6232 kernel/trace/ftrace.c 6219 6220 static int 6221 ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, 6222 int reset, int enable) 6223 { 6224 char *mod, *func, *command, *next = buf; 6225 char *tmp __free(kfree) = NULL; 6226 struct trace_array *tr = ops->private; 6227 int ret; 6228 6229 func = strsep(&next, ":"); 6230 6231 /* This can also handle :mod: parsing */ > 6232 if (next) { 6233 if (!tr) 6234 return -EINVAL; 6235 6236 command = strsep(&next, ":"); 6237 if (strcmp(command, "mod") != 0) 6238 return -EINVAL; 6239 6240 mod = next; 6241 len = command - func; 6242 /* Save the original func as ftrace_set_hash() can modify it */ 6243 tmp = kstrdup(func, GFP_KERNEL); 6244 } 6245 6246 ret = ftrace_set_hash(ops, func, len, NULL, 0, 0, reset, enable, mod); 6247 6248 if (tr && mod && ret < 0) { 6249 /* Did tmp fail to allocate? */ 6250 if (!tmp) 6251 return -ENOMEM; 6252 ret = cache_mod(tr, tmp, mod, enable); 6253 } 6254 6255 return ret; 6256 } 6257
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 2e113f8b13a2..5f6b169e3358 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -4982,10 +4982,6 @@ static int cache_mod(struct trace_array *tr, return ftrace_add_mod(tr, func, module, enable); } -static int -ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, - int reset, int enable); - #ifdef CONFIG_MODULES static void process_mod_list(struct list_head *head, struct ftrace_ops *ops, char *mod, bool enable) @@ -5788,7 +5784,7 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long *ips, static int ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, unsigned long *ips, unsigned int cnt, - int remove, int reset, int enable) + int remove, int reset, int enable, char *mod) { struct ftrace_hash **orig_hash; struct ftrace_hash *hash; @@ -5814,7 +5810,15 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, goto out_regex_unlock; } - if (buf && !ftrace_match_records(hash, buf, len)) { + if (buf && !match_records(hash, buf, len, mod)) { + /* If this was for a module and nothing was enabled, flag it */ + if (mod) + (*orig_hash)->flags |= FTRACE_HASH_FL_MOD; + + /* + * Even if it is a mod, return error to let caller know + * nothing was added + */ ret = -EINVAL; goto out_regex_unlock; } @@ -5839,7 +5843,7 @@ static int ftrace_set_addr(struct ftrace_ops *ops, unsigned long *ips, unsigned int cnt, int remove, int reset, int enable) { - return ftrace_set_hash(ops, NULL, 0, ips, cnt, remove, reset, enable); + return ftrace_set_hash(ops, NULL, 0, ips, cnt, remove, reset, enable, NULL); } #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS @@ -6217,7 +6221,38 @@ static int ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len, int reset, int enable) { - return ftrace_set_hash(ops, buf, len, NULL, 0, 0, reset, enable); + char *mod, *func, *command, *next = buf; + char *tmp __free(kfree) = NULL; + struct trace_array *tr = ops->private; + int ret; + + func = strsep(&next, ":"); + + /* This can also handle :mod: parsing */ + if (next) { + if (!tr) + return -EINVAL; + + command = strsep(&next, ":"); + if (strcmp(command, "mod") != 0) + return -EINVAL; + + mod = next; + len = command - func; + /* Save the original func as ftrace_set_hash() can modify it */ + tmp = kstrdup(func, GFP_KERNEL); + } + + ret = ftrace_set_hash(ops, func, len, NULL, 0, 0, reset, enable, mod); + + if (tr && mod && ret < 0) { + /* Did tmp fail to allocate? */ + if (!tmp) + return -ENOMEM; + ret = cache_mod(tr, tmp, mod, enable); + } + + return ret; } /** @@ -6381,6 +6416,14 @@ ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable) ftrace_ops_init(ops); + /* The trace_array is needed for caching module function filters */ + if (!ops->private) { + struct trace_array *tr = trace_get_global_array(); + + ops->private = tr; + ftrace_init_trace_array(tr); + } + while (buf) { func = strsep(&buf, ","); ftrace_set_regex(ops, func, strlen(func), 0, enable); @@ -7814,9 +7857,14 @@ static void ftrace_update_trampoline(struct ftrace_ops *ops) void ftrace_init_trace_array(struct trace_array *tr) { + if (tr->flags & TRACE_ARRAY_FL_MOD_INIT) + return; + INIT_LIST_HEAD(&tr->func_probes); INIT_LIST_HEAD(&tr->mod_trace); INIT_LIST_HEAD(&tr->mod_notrace); + + tr->flags |= TRACE_ARRAY_FL_MOD_INIT; } #else @@ -7845,7 +7893,8 @@ static void ftrace_update_trampoline(struct ftrace_ops *ops) __init void ftrace_init_global_array_ops(struct trace_array *tr) { tr->ops = &global_ops; - tr->ops->private = tr; + if (!global_ops.private) + global_ops.private = tr; ftrace_init_trace_array(tr); init_array_fgraph_ops(tr, tr->ops); } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f8aebcb01e62..5451f3e2e17b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -10660,6 +10660,12 @@ __init static int tracer_alloc_buffers(void) return ret; } +/* Used to set module cached ftrace filtering at boot up */ +__init struct trace_array *trace_get_global_array(void) +{ + return &global_trace; +} + void __init ftrace_boot_snapshot(void) { #ifdef CONFIG_TRACER_MAX_TRACE diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 9691b47b5f3d..b6e60013ce0f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -432,6 +432,7 @@ struct trace_array { enum { TRACE_ARRAY_FL_GLOBAL = BIT(0), TRACE_ARRAY_FL_BOOT = BIT(1), + TRACE_ARRAY_FL_MOD_INIT = BIT(2), }; extern struct list_head ftrace_trace_arrays; @@ -1114,6 +1115,7 @@ void ftrace_destroy_function_files(struct trace_array *tr); int ftrace_allocate_ftrace_ops(struct trace_array *tr); void ftrace_free_ftrace_ops(struct trace_array *tr); void ftrace_init_global_array_ops(struct trace_array *tr); +struct trace_array *trace_get_global_array(void); void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func); void ftrace_reset_array_ops(struct trace_array *tr); void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);