Hi Song, I love your patch! Yet something to improve: [auto build test ERROR on bpf-next/master] url: https://github.com/intel-lab-lkp/linux/commits/Song-Liu/ftrace-host-klp-and-bpf-trampoline-together/20220718-081533 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: powerpc-randconfig-r023-20220717 (https://download.01.org/0day-ci/archive/20220718/202207181116.PO2cQ09B-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project d74b88c69dc2644bd0dc5d64e2d7413a0d4040e5) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://github.com/intel-lab-lkp/linux/commit/1535f287d288f9b7540ec50f56da1fe437ac6512 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Song-Liu/ftrace-host-klp-and-bpf-trampoline-together/20220718-081533 git checkout 1535f287d288f9b7540ec50f56da1fe437ac6512 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash kernel/trace/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): kernel/trace/ftrace.c:299:5: warning: no previous prototype for function '__register_ftrace_function' [-Wmissing-prototypes] int __register_ftrace_function(struct ftrace_ops *ops) ^ kernel/trace/ftrace.c:299:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int __register_ftrace_function(struct ftrace_ops *ops) ^ static kernel/trace/ftrace.c:342:5: warning: no previous prototype for function '__unregister_ftrace_function' [-Wmissing-prototypes] int __unregister_ftrace_function(struct ftrace_ops *ops) ^ kernel/trace/ftrace.c:342:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int __unregister_ftrace_function(struct ftrace_ops *ops) ^ static kernel/trace/ftrace.c:4030:15: warning: no previous prototype for function 'arch_ftrace_match_adjust' [-Wmissing-prototypes] char * __weak arch_ftrace_match_adjust(char *str, const char *search) ^ kernel/trace/ftrace.c:4030:1: note: declare 'static' if the function is not intended to be used outside of this translation unit char * __weak arch_ftrace_match_adjust(char *str, const char *search) ^ static >> kernel/trace/ftrace.c:8082:14: error: use of undeclared identifier 'direct_mutex'; did you mean 'event_mutex'? mutex_lock(&direct_mutex); ^~~~~~~~~~~~ event_mutex include/linux/mutex.h:187:44: note: expanded from macro 'mutex_lock' #define mutex_lock(lock) mutex_lock_nested(lock, 0) ^ kernel/trace/trace.h:1523:21: note: 'event_mutex' declared here extern struct mutex event_mutex; ^ kernel/trace/ftrace.c:8122:16: error: use of undeclared identifier 'direct_mutex'; did you mean 'event_mutex'? mutex_unlock(&direct_mutex); ^~~~~~~~~~~~ event_mutex kernel/trace/trace.h:1523:21: note: 'event_mutex' declared here extern struct mutex event_mutex; ^ kernel/trace/ftrace.c:8158:17: error: use of undeclared identifier 'direct_mutex'; did you mean 'event_mutex'? mutex_unlock(&direct_mutex); ^~~~~~~~~~~~ event_mutex kernel/trace/trace.h:1523:21: note: 'event_mutex' declared here extern struct mutex event_mutex; ^ kernel/trace/ftrace.c:8178:14: error: use of undeclared identifier 'direct_mutex'; did you mean 'event_mutex'? mutex_lock(&direct_mutex); ^~~~~~~~~~~~ event_mutex include/linux/mutex.h:187:44: note: expanded from macro 'mutex_lock' #define mutex_lock(lock) mutex_lock_nested(lock, 0) ^ kernel/trace/trace.h:1523:21: note: 'event_mutex' declared here extern struct mutex event_mutex; ^ kernel/trace/ftrace.c:8203:16: error: use of undeclared identifier 'direct_mutex'; did you mean 'event_mutex'? mutex_unlock(&direct_mutex); ^~~~~~~~~~~~ event_mutex kernel/trace/trace.h:1523:21: note: 'event_mutex' declared here extern struct mutex event_mutex; ^ 3 warnings and 5 errors generated. vim +8082 kernel/trace/ftrace.c 8051 8052 /* 8053 * When registering ftrace_ops with IPMODIFY, it is necessary to make sure 8054 * it doesn't conflict with any direct ftrace_ops. If there is existing 8055 * direct ftrace_ops on a kernel function being patched, call 8056 * FTRACE_OPS_CMD_ENABLE_SHARE_IPMODIFY_PEER on it to enable sharing. 8057 * 8058 * @ops: ftrace_ops being registered. 8059 * 8060 * Returns: 8061 * 0 - @ops does not have IPMODIFY or @ops itself is DIRECT, no 8062 * change needed; 8063 * 1 - @ops has IPMODIFY, hold direct_mutex; 8064 * -EBUSY - currently registered DIRECT ftrace_ops cannot share the 8065 * same function with IPMODIFY, abort the register. 8066 * -EAGAIN - cannot make changes to currently registered DIRECT 8067 * ftrace_ops due to rare race conditions. Should retry 8068 * later. This is needed to avoid potential deadlocks 8069 * on the DIRECT ftrace_ops side. 8070 */ 8071 static int prepare_direct_functions_for_ipmodify(struct ftrace_ops *ops) 8072 __acquires(&direct_mutex) 8073 { 8074 struct ftrace_func_entry *entry; 8075 struct ftrace_hash *hash; 8076 struct ftrace_ops *op; 8077 int size, i, ret; 8078 8079 if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY)) 8080 return 0; 8081 > 8082 mutex_lock(&direct_mutex); 8083 8084 hash = ops->func_hash->filter_hash; 8085 size = 1 << hash->size_bits; 8086 for (i = 0; i < size; i++) { 8087 hlist_for_each_entry(entry, &hash->buckets[i], hlist) { 8088 unsigned long ip = entry->ip; 8089 bool found_op = false; 8090 8091 mutex_lock(&ftrace_lock); 8092 do_for_each_ftrace_op(op, ftrace_ops_list) { 8093 if (!(op->flags & FTRACE_OPS_FL_DIRECT)) 8094 continue; 8095 if (ops_references_ip(op, ip)) { 8096 found_op = true; 8097 break; 8098 } 8099 } while_for_each_ftrace_op(op); 8100 mutex_unlock(&ftrace_lock); 8101 8102 if (found_op) { 8103 if (!op->ops_func) { 8104 ret = -EBUSY; 8105 goto err_out; 8106 } 8107 ret = op->ops_func(op, FTRACE_OPS_CMD_ENABLE_SHARE_IPMODIFY_PEER); 8108 if (ret) 8109 goto err_out; 8110 } 8111 } 8112 } 8113 8114 /* 8115 * Didn't find any overlap with direct ftrace_ops, or the direct 8116 * function can share with ipmodify. Hold direct_mutex to make sure 8117 * this doesn't change until we are done. 8118 */ 8119 return 1; 8120 8121 err_out: 8122 mutex_unlock(&direct_mutex); 8123 return ret; 8124 } 8125 -- 0-DAY CI Kernel Test Service https://01.org/lkp
