Subject: Re: 3.11-rc7:BUG: soft lockup

From: Baoquan He <[email-masked]>
Date: Mon, 02 Sep 2013 20:09:02 +0800

On 09/02/2013 05:04 PM, Ding Tianhong wrote:
> On 2013/9/2 16:24, Baoquan He wrote:
>> Hi Tianhong,
>>
>> I applied your patch and execute below cmd. 
>> Then keyboard inputting problems happened, 
>> I can't enter user/password correctly, then reboot again, it's OK now.
> Thanks for your work, I don't understand that the keyboard problem is the patch fault or your system problem, 
> if it is not happen again, I think the problem is fixed.

Yeah,  I will wait and see if it will happen again. Up to now, it's OK.

Thank you all for help.

Baoquan
Thanks

>
>> The original bug still can't be reproduced.
>>
>> make SUBDIRS=net/bridge/netfilter/
>> cp /net/bridge/netfilter/ebtables.ko
>> /lib/modules/3.11.0-rc7+/kernel/net/bridge/netfilter/ebtables.ko
>> depmod
>> modprobe ebtables.ko
>> reboot
>>
>> Baoquan
>> Thanks
>>
>>> please try this patch and give me the result, thanks.
>>>
>>> Return the correct value if mutex_lock_interruptible() failed, avoid
>>> confusion with that the modules is not exist, and deal with the return
>>> value in right way.
>>>
>>> if mutex_lock_interrupt() failed, sh
>>>
>>> Signed-off-by: root <[email-masked]>
>>> ---
>>>  net/bridge/netfilter/ebtables.c | 17 +++++++----------
>>>  1 file changed, 7 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
>>> index ac78024..e7fe9f8 100644
>>> --- a/net/bridge/netfilter/ebtables.c
>>> +++ b/net/bridge/netfilter/ebtables.c
>>> @@ -322,17 +322,14 @@ static inline void *
>>>  find_inlist_lock_noload(struct list_head *head, const char *name, int *error,
>>>     struct mutex *mutex)
>>>  {
>>> -	struct {
>>> -		struct list_head list;
>>> -		char name[EBT_FUNCTION_MAXNAMELEN];
>>> -	} *e;
>>> +	struct ebt_table *e;
>>>  
>>>  	*error = mutex_lock_interruptible(mutex);
>>>  	if (*error != 0)
>>> -		return NULL;
>>> +		return ERR_PTR(-EINTR);
>>>  
>>>  	list_for_each_entry(e, head, list) {
>>> -		if (strcmp(e->name, name) == 0)
>>> +		 if (strcmp(e->name, name) == 0 && try_module_get(e->me))
>>>  			return e;
>>>  	}
>>>  	*error = -ENOENT;
>>> @@ -1005,7 +1002,7 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl,
>>>  		goto free_counterstmp;
>>>  
>>>  	t = find_table_lock(net, repl->name, &ret, &ebt_mutex);
>>> -	if (!t) {
>>> +	if (IS_ERR_OR_NULL(t)) {
>>>  		ret = -ENOENT;
>>>  		goto free_iterate;
>>>  	}
>>> @@ -1284,7 +1281,7 @@ static int do_update_counters(struct net *net, const char *name,
>>>  		return -ENOMEM;
>>>  
>>>  	t = find_table_lock(net, name, &ret, &ebt_mutex);
>>> -	if (!t)
>>> +	if (IS_ERR_OR_NULL(t))
>>>  		goto free_tmp;
>>>  
>>>  	if (num_counters != t->private->nentries) {
>>> @@ -1504,7 +1501,7 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
>>>  		return -EFAULT;
>>>  
>>>  	t = find_table_lock(net, tmp.name, &ret, &ebt_mutex);
>>> -	if (!t)
>>> +	if (IS_ERR_OR_NULL(t))
>>>  		return ret;
>>>  
>>>  	switch(cmd) {
>>> @@ -2319,7 +2316,7 @@ static int compat_do_ebt_get_ctl(struct sock *sk, int cmd,
>>>  		return -EFAULT;
>>>  
>>>  	t = find_table_lock(net, tmp.name, &ret, &ebt_mutex);
>>> -	if (!t)
>>> +	if (IS_ERR_OR_NULL(t))
>>>  		return ret;
>>>  
>>>  	xt_compat_lock(NFPROTO_BRIDGE);
>>
>> .
>>
>