Hello Namjae Jeon,
The patch f44158485826: "cifsd: add file operations" from Mar 16,
2021, leads to the following
Smatch static checker warning:
fs/xattr.c:524 vfs_removexattr()
warn: sleeping in atomic context
fs/xattr.c
514
515 int
516 vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry,
517 const char *name)
518 {
519 struct inode *inode = dentry->d_inode;
520 struct inode *delegated_inode = NULL;
521 int error;
522
523 retry_deleg:
--> 524 inode_lock(inode);
525 error = __vfs_removexattr_locked(mnt_userns, dentry,
526 name, &delegated_inode);
527 inode_unlock(inode);
528
529 if (delegated_inode) {
530 error = break_deleg_wait(&delegated_inode);
531 if (!error)
532 goto retry_deleg;
533 }
534
535 return error;
536 }
The call tree is (slight edited).
ksmbd_file_table_flush() <- disables preempt
-> ksmbd_vfs_fsync()
-> ksmbd_fd_put()
-> __put_fd_final()
-> __ksmbd_close_fd()
-> __ksmbd_inode_close()
-> ksmbd_vfs_remove_xattr()
-> vfs_removexattr()
fs/ksmbd/vfs_cache.c
669 int ksmbd_file_table_flush(struct ksmbd_work *work)
670 {
671 struct ksmbd_file *fp = NULL;
672 unsigned int id;
673 int ret;
674
675 read_lock(&work->sess->file_table.lock);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Disables preemption.
676 idr_for_each_entry(work->sess->file_table.idr, fp, id) {
677 ret = ksmbd_vfs_fsync(work, fp->volatile_id, KSMBD_NO_FID);
678 if (ret)
679 break;
680 }
681 read_unlock(&work->sess->file_table.lock);
682 return ret;
683 }
Hopefully this bug report is clear why Smatch is complaining. Let me
know if you have any questions.
regards,
dan carpenter
