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charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: Al Viro On Fri, Jan 30, 2026 at 05:05:34PM -0800, Samuel Wu wrote: > > How lovely... Could you slap > > WARN_ON(ret == -EAGAIN); > > right before that > > if (ret < 0) > > return ret; > > Surprisingly ret == 0 every time, so no difference in dmesg logs with > this addition. What the hell? Other than that mutex_lock(), the only change in there is the order of store to file->private_data and call of ffs_data_opened(); that struct file pointer is not visible to anyone at that point... Wait, it also brings ffs_data_reset() on that transition under ffs->mutex... For a quick check: does git fetch git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git for-wsamuel2 git switch --detach FETCH_HEAD demonstrate the same breakage?