From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 88D30138483; Tue, 6 Feb 2024 12:09:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707221362; cv=none; b=pOGe1UM4ahG09RGS38FXETeyaJfKRLtCTWeOfC2BI7W78NmaZ9l3n/ocW6OpGp9GVv21WA/EgNhi9R+dkZbkxw9OAkOzCQCysoAZxhZcyYHDwzYQ/3AYkbPZrP2nWd0jJywU8mD25APcPbDY57dySxl3EaJ+yyvlG2tZQIrc6a0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707221362; c=relaxed/simple; bh=KWJDRqmuSA25gha7hUXBxRETKbAFvLCSdo+JgHjFgUw=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=jd39vp9jKzcOLS384JbeVi1YImJkEvvmaWPDGLiEu9/uYdfxHIeAUQRItr56obtqxPA2reO6KYUrTc9Xkhrbl/jPLuzfYSO1ec3+cddrFCZ7LcUB8qPi49cXKtdVOUpXTFD3jven1Ak+3xF5V1mFDebLRK4jlo+kh7w/j6+ZbXY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 754BBC433F1; Tue, 6 Feb 2024 12:09:22 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from ) id 1rXKGs-00000006bEq-3oIR; Tue, 06 Feb 2024 07:09:50 -0500 Message-ID: <20240206120950.772179769@rostedt.homelinux.com> User-Agent: quilt/0.67 Date: Tue, 06 Feb 2024 07:09:32 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Linus Torvalds , Greg Kroah-Hartman , Sasha Levin , Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Josef Bacik Subject: [v6.6][PATCH 27/57] eventfs: Move taking of inode_lock into dcache_dir_open_wrapper() References: <20240206120905.570408983@rostedt.homelinux.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 From: "Steven Rostedt (Google)" The both create_file_dentry() and create_dir_dentry() takes a boolean parameter "lookup", as on lookup the inode_lock should already be taken, but for dcache_dir_open_wrapper() it is not taken. There's no reason that the dcache_dir_open_wrapper() can't take the inode_lock before calling these functions. In fact, it's better if it does, as the lock can be held throughout both directory and file creations. This also simplifies the code, and possibly prevents unexpected race conditions when the lock is released. Link: https://lkml.kernel.org/r/20231121231112.528544825@goodmis.org Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Andrew Morton Fixes: 5790b1fb3d672 ("eventfs: Remove eventfs_file and just use eventfs_inode") Reviewed-by: Josef Bacik Signed-off-by: Steven Rostedt (Google) (cherry picked from commit bcae32c5632fc0a0dbce46fa731cd23403117e66) --- fs/tracefs/event_inode.c | 16 ++-------------- 1 file changed, 2 insertions(+), 14 deletions(-) diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 56d192f0ead8..590e8176449b 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -347,15 +347,8 @@ create_file_dentry(struct eventfs_inode *ei, int idx, mutex_unlock(&eventfs_mutex); - /* The lookup already has the parent->d_inode locked */ - if (!lookup) - inode_lock(parent->d_inode); - dentry = create_file(name, mode, attr, parent, data, fops); - if (!lookup) - inode_unlock(parent->d_inode); - mutex_lock(&eventfs_mutex); if (IS_ERR_OR_NULL(dentry)) { @@ -453,15 +446,8 @@ create_dir_dentry(struct eventfs_inode *pei, struct eventfs_inode *ei, } mutex_unlock(&eventfs_mutex); - /* The lookup already has the parent->d_inode locked */ - if (!lookup) - inode_lock(parent->d_inode); - dentry = create_dir(ei, parent); - if (!lookup) - inode_unlock(parent->d_inode); - mutex_lock(&eventfs_mutex); if (IS_ERR_OR_NULL(dentry) && !ei->is_freed) { @@ -693,6 +679,7 @@ static int dcache_dir_open_wrapper(struct inode *inode, struct file *file) return -ENOMEM; } + inode_lock(parent->d_inode); list_for_each_entry_srcu(ei_child, &ei->children, list, srcu_read_lock_held(&eventfs_srcu)) { d = create_dir_dentry(ei, ei_child, parent, false); @@ -725,6 +712,7 @@ static int dcache_dir_open_wrapper(struct inode *inode, struct file *file) cnt++; } } + inode_unlock(parent->d_inode); srcu_read_unlock(&eventfs_srcu, idx); ret = dcache_dir_open(inode, file); -- 2.43.0