Re: Bug in Kernel 6.8.x, 6.9.x Causing Trace/Panic During Shutdown/Reboot

[Linux regression tracking (Thorsten Leemhuis)]

Hi, Thorsten here, the Linux kernel's regression tracker. Top-posting
for once, to make this easily accessible to everyone.

Ilkka or Steven, what happened to this? This thread looks stalled. I
also was unsuccessful when looking for other threads related to this
report or the culprit. Did it fall through the cracks or am I missing
something here?

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
Everything you wanna know about Linux kernel regression tracking:
https://linux-regtracking.leemhuis.info/about/#tldr
If I did something stupid, please tell me, as explained on that page.

#regzbot poke

On 02.06.24 09:32, Ilkka Naulapää wrote:
> sorry longer delay, been a bit busy but here is the result from that
> new patch. Only applied this patch so if the previous one is needed
> also, let me know and I'll rerun it.
> 
> --Ilkka
> 
> On Thu, May 30, 2024 at 5:00 PM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>>
>> On Thu, 30 May 2024 16:02:37 +0300
>> Ilkka Naulapää <digirigawa@xxxxxxxxx> wrote:
>>
>>> applied your patch and here's the output.
>>>
>>
>> Unfortunately, it doesn't give me any new information. I added one more
>> BUG on, want to try this? Otherwise, I'm pretty much at a lost. :-/
>>
>> -- Steve
>>
>> diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
>> index de5b72216b1a..a090495e78c9 100644
>> --- a/fs/tracefs/inode.c
>> +++ b/fs/tracefs/inode.c
>> @@ -39,13 +39,17 @@ static struct inode *tracefs_alloc_inode(struct super_block *sb)
>>                 return NULL;
>>
>>         ti->flags = 0;
>> +       ti->magic = 20240823;
>>
>>         return &ti->vfs_inode;
>>  }
>>
>>  static void tracefs_free_inode(struct inode *inode)
>>  {
>> -       kmem_cache_free(tracefs_inode_cachep, get_tracefs(inode));
>> +       struct tracefs_inode *ti = get_tracefs(inode);
>> +
>> +       BUG_ON(ti->magic != 20240823);
>> +       kmem_cache_free(tracefs_inode_cachep, ti);
>>  }
>>
>>  static ssize_t default_read_file(struct file *file, char __user *buf,
>> @@ -147,16 +151,6 @@ static const struct inode_operations tracefs_dir_inode_operations = {
>>         .rmdir          = tracefs_syscall_rmdir,
>>  };
>>
>> -struct inode *tracefs_get_inode(struct super_block *sb)
>> -{
>> -       struct inode *inode = new_inode(sb);
>> -       if (inode) {
>> -               inode->i_ino = get_next_ino();
>> -               inode->i_atime = inode->i_mtime = inode_set_ctime_current(inode);
>> -       }
>> -       return inode;
>> -}
>> -
>>  struct tracefs_mount_opts {
>>         kuid_t uid;
>>         kgid_t gid;
>> @@ -384,6 +378,7 @@ static void tracefs_dentry_iput(struct dentry *dentry, struct inode *inode)
>>                 return;
>>
>>         ti = get_tracefs(inode);
>> +       BUG_ON(ti->magic != 20240823);
>>         if (ti && ti->flags & TRACEFS_EVENT_INODE)
>>                 eventfs_set_ef_status_free(dentry);
>>         iput(inode);
>> @@ -568,6 +563,18 @@ struct dentry *eventfs_end_creating(struct dentry *dentry)
>>         return dentry;
>>  }
>>
>> +struct inode *tracefs_get_inode(struct super_block *sb)
>> +{
>> +       struct inode *inode = new_inode(sb);
>> +
>> +       BUG_ON(sb->s_op != &tracefs_super_operations);
>> +       if (inode) {
>> +               inode->i_ino = get_next_ino();
>> +               inode->i_atime = inode->i_mtime = inode_set_ctime_current(inode);
>> +       }
>> +       return inode;
>> +}
>> +
>>  /**
>>   * tracefs_create_file - create a file in the tracefs filesystem
>>   * @name: a pointer to a string containing the name of the file to create.
>> diff --git a/fs/tracefs/internal.h b/fs/tracefs/internal.h
>> index 69c2b1d87c46..9059b8b11bb6 100644
>> --- a/fs/tracefs/internal.h
>> +++ b/fs/tracefs/internal.h
>> @@ -9,12 +9,15 @@ enum {
>>  struct tracefs_inode {
>>         unsigned long           flags;
>>         void                    *private;
>> +       unsigned long           magic;
>>         struct inode            vfs_inode;
>>  };
>>
>>  static inline struct tracefs_inode *get_tracefs(const struct inode *inode)
>>  {
>> -       return container_of(inode, struct tracefs_inode, vfs_inode);
>> +       struct tracefs_inode *ti = container_of(inode, struct tracefs_inode, vfs_inode);
>> +       BUG_ON(ti->magic != 20240823);
>> +       return ti;
>>  }
>>
>>  struct dentry *tracefs_start_creating(const char *name, struct dentry *parent);