All of lore.kernel.org
 help / color / mirror / Atom feed
From: kernel test robot <lkp@intel.com>
To: kbuild@lists.01.org
Subject: [jolsa-perf:ftrace/direct 5/8] kernel/trace/ftrace.c:5150 register_ftrace_direct() error: uninitialized symbol 'entry'.
Date: Wed, 01 Sep 2021 05:32:51 +0800	[thread overview]
Message-ID: <202109010541.2HLm1TVa-lkp@intel.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 9657 bytes --]

CC: kbuild-all(a)lists.01.org
CC: linux-kernel(a)vger.kernel.org
TO: Jiri Olsa <jolsa@kernel.org>

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
:::::: branch date: 12 hours ago
:::::: commit date: 12 hours ago
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 <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
kernel/trace/ftrace.c:5150 register_ftrace_direct() error: uninitialized symbol 'entry'.

vim +/entry +5150 kernel/trace/ftrace.c

8a141dd7f7060d Alexei Starovoitov      2021-03-16  5093  
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5094) /**
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5095)  * register_ftrace_direct - Call a custom trampoline directly
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5096)  * @ip: The address of the nop at the beginning of a function
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5097)  * @addr: The address of the trampoline to call at @ip
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5098)  *
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5099)  * This is used to connect a direct call from the nop location (@ip)
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5100)  * at the start of ftrace traced functions. The location that it calls
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5101)  * (@addr) must be able to handle a direct call, and save the parameters
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5102)  * of the function being traced, and restore them (or inject new ones
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5103)  * if needed), before returning.
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5104)  *
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5105)  * Returns:
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5106)  *  0 on success
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5107)  *  -EBUSY - Another direct function is already attached (there can be only one)
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5108)  *  -ENODEV - @ip does not point to a ftrace nop location (or not supported)
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5109)  *  -ENOMEM - There was an allocation failure.
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5110)  */
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);
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;
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) }
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5193) EXPORT_SYMBOL_GPL(register_ftrace_direct);
763e34e74bb7d5 Steven Rostedt (VMware  2019-11-08  5194) 

:::::: The code at line 5150 was first introduced by commit
:::::: 013bf0da0474816f57739daa006c8564ad7396a3 ftrace: Add ftrace_find_direct_func()

:::::: TO: Steven Rostedt (VMware) <rostedt@goodmis.org>
:::::: CC: Steven Rostedt (VMware) <rostedt@goodmis.org>

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 33420 bytes --]

WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: kbuild-all@lists.01.org
Subject: [jolsa-perf:ftrace/direct 5/8] kernel/trace/ftrace.c:5150 register_ftrace_direct() error: uninitialized symbol 'entry'.
Date: Wed, 01 Sep 2021 13:27:17 +0300	[thread overview]
Message-ID: <202109010541.2HLm1TVa-lkp@intel.com> (raw)

[-- Attachment #1: Type: text/plain, Size: 7543 bytes --]

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 <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

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

WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: kbuild@lists.01.org, Jiri Olsa <jolsa@kernel.org>
Cc: lkp@intel.com, kbuild-all@lists.01.org, linux-kernel@vger.kernel.org
Subject: [jolsa-perf:ftrace/direct 5/8] kernel/trace/ftrace.c:5150 register_ftrace_direct() error: uninitialized symbol 'entry'.
Date: Wed, 1 Sep 2021 13:27:17 +0300	[thread overview]
Message-ID: <202109010541.2HLm1TVa-lkp@intel.com> (raw)

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 <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

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@lists.01.org


             reply	other threads:[~2021-08-31 21:32 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-31 21:32 kernel test robot [this message]
2021-09-01 10:27 ` [jolsa-perf:ftrace/direct 5/8] kernel/trace/ftrace.c:5150 register_ftrace_direct() error: uninitialized symbol 'entry' Dan Carpenter
2021-09-01 10:27 ` Dan Carpenter
2021-09-02 14:09 ` Jiri Olsa
2021-09-02 14:09   ` Jiri Olsa

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=202109010541.2HLm1TVa-lkp@intel.com \
    --to=lkp@intel.com \
    --cc=kbuild@lists.01.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.