On Wed, Sep 01, 2021 at 01:27:17PM +0300, Dan Carpenter wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git ftrace/direct > head: 95a037919f1906d8bf164fb0c0066c9f298df139 > commit: b45bdf4de5473d5c15090eceeb72a2d5082cde2d [5/8] ftrace: Add ftrace_add_rec_direct function > config: x86_64-randconfig-m001-20210831 (attached as .config) > compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot > Reported-by: Dan Carpenter Steven, I have fix for this one.. I'll wait if there are any review comments and then post all together thanks, jirka > > smatch warnings: > kernel/trace/ftrace.c:5150 register_ftrace_direct() error: uninitialized symbol 'entry'. > > vim +/entry +5150 kernel/trace/ftrace.c > > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5111) int register_ftrace_direct(unsigned long ip, unsigned long addr) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5112) { > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5113) struct ftrace_direct_func *direct; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5114) struct ftrace_func_entry *entry; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5115) struct ftrace_hash *free_hash = NULL; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5116) struct dyn_ftrace *rec; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5117) int ret = -EBUSY; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5118) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5119) mutex_lock(&direct_mutex); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5120) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5121) /* See if there's a direct function at @ip already */ > ff205766dbbee0 Alexei Starovoitov 2019-12-08 5122 if (ftrace_find_rec_direct(ip)) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5123) goto out_unlock; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5124) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5125) ret = -ENODEV; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5126) rec = lookup_rec(ip, ip); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5127) if (!rec) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5128) goto out_unlock; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5129) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5130) /* > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5131) * Check if the rec says it has a direct call but we didn't > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5132) * find one earlier? > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5133) */ > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5134) if (WARN_ON(rec->flags & FTRACE_FL_DIRECT)) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5135) goto out_unlock; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5136) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5137) /* Make sure the ip points to the exact record */ > 406acdd32d3e7d Steven Rostedt (VMware 2019-11-15 5138) if (ip != rec->ip) { > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5139) ip = rec->ip; > 406acdd32d3e7d Steven Rostedt (VMware 2019-11-15 5140) /* Need to check this ip for a direct. */ > ff205766dbbee0 Alexei Starovoitov 2019-12-08 5141 if (ftrace_find_rec_direct(ip)) > 406acdd32d3e7d Steven Rostedt (VMware 2019-11-15 5142) goto out_unlock; > 406acdd32d3e7d Steven Rostedt (VMware 2019-11-15 5143) } > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5144) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5145) ret = -ENOMEM; > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5146) direct = ftrace_find_direct_func(addr); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5147) if (!direct) { > 8a141dd7f7060d Alexei Starovoitov 2021-03-16 5148 direct = ftrace_alloc_direct_func(addr); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5149) if (!direct) { > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 @5150) kfree(entry); > > Delete this kfree. "entry" isn't initialized yet. > > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5151) goto out_unlock; > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5152) } > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5153) } > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5154) > b45bdf4de5473d Jiri Olsa 2021-05-18 5155 entry = ftrace_add_rec_direct(ip, addr, &free_hash); > ^^^^^^ > > b45bdf4de5473d Jiri Olsa 2021-05-18 5156 if (!entry) > b45bdf4de5473d Jiri Olsa 2021-05-18 5157 goto out_unlock; > > This patch should probably do free direct or something. The error > handling in this function is quite confusing so I'm not exactly sure. > > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5158) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5159) ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5160) if (ret) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5161) remove_hash_entry(direct_functions, entry); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5162) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5163) if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) { > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5164) ret = register_ftrace_function(&direct_ops); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5165) if (ret) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5166) ftrace_set_filter_ip(&direct_ops, ip, 1, 0); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5167) } > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5168) > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5169) if (ret) { > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5170) kfree(entry); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5171) if (!direct->count) { > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5172) list_del_rcu(&direct->next); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5173) synchronize_rcu_tasks(); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5174) kfree(direct); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5175) if (free_hash) > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5176) free_ftrace_hash(free_hash); > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5177) free_hash = NULL; > a3ad1a7e396890 Steven Rostedt (VMware 2019-11-08 5178) ftrace_direct_func_count--; > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5179) } > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5180) } else { > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5181) direct->count++; > 013bf0da047481 Steven Rostedt (VMware 2019-11-08 5182) } > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5183) out_unlock: > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5184) mutex_unlock(&direct_mutex); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5185) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5186) if (free_hash) { > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5187) synchronize_rcu_tasks(); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5188) free_ftrace_hash(free_hash); > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5189) } > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5190) > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5191) return ret; > 763e34e74bb7d5 Steven Rostedt (VMware 2019-11-08 5192) } > > --- > 0-DAY CI Kernel Test Service, Intel Corporation > https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org >