Re: [PATCH] ocfs2: embed actual values into ocfs2_sysfile_lock_key names

[Tetsuo Handa]

On 2025/06/30 11:42, Heming Zhao wrote:
> I am not familiar with lockdep, and just have two questions regarding
> the lockdep in ocfs2.
> 
> 1>
> there are three global "static struct lock_class_key" definitions:
> - fs/ocfs2/inode.c  : ocfs2_sysfile_lock_key[NUM_SYSTEM_INODES]
> - fs/ocfs2/dlmglue.c: lockdep_keys[OCFS2_NUM_LOCK_TYPES]
> - fs/ocfs2/sysfile.c: ocfs2_sysfile_cluster_lock_key[NUM_SYSTEM_INODES]
> 
> why did you env only trigger the ocfs2_sysfile_lock_key[] warning?

Because syzbot is reporting lockdep warning on ocfs2_sysfile_lock_key
at https://syzkaller.appspot.com/bug?extid=68c788938ba0326046a9 and
I couldn't find which lock_class_key syzbot is reporting.

Unless you want me to update all keys within this patch, you can submit
similar changes on lockdep_keys and ocfs2_sysfile_cluster_lock_key as
separate patches.

> 
> 2>
> It seems the existing CONFIG_DEBUG_LOCK_ALLOC is incorrect, it should be
> replaced with CONFIG_LOCKDEP.

I couldn't catch what you mean. There are many modules which declare
"struct lock_class_key" under CONFIG_DEBUG_LOCK_ALLOC=y.