From nobody Mon Feb 9 13:36:26 2026 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (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 685BC296BDC; Wed, 24 Dec 2025 03:30:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766547006; cv=pass; b=WUkAAkMwCWPjnk7W0/cQDDIcuTPVvnGGpiwPMapOWtghq943jU+z73ZDTPb5U4a4srvgHI1LOzZkBVnavdYJIiWMZpt7m4Ft4iDPRR+yH8NBT+6q9uSTgw+daNI7pJEKfkYXzeMZOnMQtG/yDk3dxrxbT/7GsGsM8fgrb3Xeco8= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766547006; c=relaxed/simple; bh=rBPBL/Vb8Hw/d3o10YSURgcEebSW3b8ZLT5xTWdOyok=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t6ouWNMjCJxnxSLlfue6BWnJRtOvBmH8E9WWYG91nuHJZX+EQUtbj4PekmRPbwj3X8TWPuH1zVoSr9safNnGBu1OPBfZjcZugvm83YCF/oTt0+uzpdUkryMrHiZwiV4G/NO6+nl/FCgdZ443wvqm+Xq2az+Jm7qMqGH0VCLqzJg= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux.beauty; spf=pass smtp.mailfrom=linux.beauty; dkim=pass (1024-bit key) header.d=linux.beauty header.i=me@linux.beauty header.b=Ym/brqct; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux.beauty Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.beauty Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.beauty header.i=me@linux.beauty header.b="Ym/brqct" ARC-Seal: i=1; a=rsa-sha256; t=1766546992; cv=none; d=zohomail.com; s=zohoarc; b=NggRZdUh7loRZMU03jxtsbP1lkxG1qMMlfEoGEY64NSNQ/SsBHe+b2E+nK/h3mSOEOtS972JvGLRfvoJ5hH79EWe0LLQIMnpgsVi4/z6mMtFasdkXG3s9f7eeliHg8hnxCc4m831OU/Z4svmDBx636fyIoFNQSBv/1vcE6x2e4Q= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1766546992; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=pgvFPCJXhtluCAV66VL90Qhj7kF7VLamnOW1x72E0H8=; b=UgGaYISkipVknw4nT3nAfMbMzy6OIeUOTjfFdq9sVprgZyIv1DxtybXrXf4v2JDrcse+jC5B+4ACQPE8jn3vMeQU/Le5EfoR18BYd/610CJp/EzTHgU4C7AKvwzKcZrDNfiCasWgZvW955bbHQjck6W6Sxkzey/j0ehmMOq00cI= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=linux.beauty; spf=pass smtp.mailfrom=me@linux.beauty; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1766546991; s=zmail; d=linux.beauty; i=me@linux.beauty; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=pgvFPCJXhtluCAV66VL90Qhj7kF7VLamnOW1x72E0H8=; b=Ym/brqctNxTCBN5Isw100DdpX09KFzDNVZo6MfHUZPN4hTUzEBpQEVmFggoKNSdN UhBh+OVZEflACkmY8inlfXyg7+zFB6J+8klSZ2/ShkiHxxp/cIB4BoIb22a1vL3xfCc PmX6w5HmoWN7TLmvDW5wiG2qv0uvhMUJDL58eMS0= Received: by mx.zohomail.com with SMTPS id 17665469898281022.4434469429821; Tue, 23 Dec 2025 19:29:49 -0800 (PST) From: Li Chen To: "Theodore Ts'o" , Andreas Dilger , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Li Chen Subject: [RFC v3 1/2] ext4: fast_commit: assert i_data_sem only before sleep Date: Wed, 24 Dec 2025 11:29:41 +0800 Message-ID: <20251224032943.134063-2-me@linux.beauty> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251224032943.134063-1-me@linux.beauty> References: <20251224032943.134063-1-me@linux.beauty> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External Content-Type: text/plain; charset="utf-8" ext4_fc_track_inode() can return without sleeping when EXT4_STATE_FC_COMMITTING is already clear. The lockdep assertion for ei->i_data_sem was done unconditionally before the wait loop, which can WARN in call paths that hold i_data_sem even though we never block. Move lockdep_assert_not_held(&ei->i_data_sem) into the actual sleep path, right before schedule(). Signed-off-by: Li Chen --- fs/ext4/fast_commit.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index d0926967d086..b0c458082997 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -566,13 +566,6 @@ void ext4_fc_track_inode(handle_t *handle, struct inod= e *inode) if (ext4_test_mount_flag(inode->i_sb, EXT4_MF_FC_INELIGIBLE)) return; =20 - /* - * If we come here, we may sleep while waiting for the inode to - * commit. We shouldn't be holding i_data_sem when we go to sleep since - * the commit path needs to grab the lock while committing the inode. - */ - lockdep_assert_not_held(&ei->i_data_sem); - while (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) { #if (BITS_PER_LONG < 64) DEFINE_WAIT_BIT(wait, &ei->i_state_flags, @@ -586,8 +579,16 @@ void ext4_fc_track_inode(handle_t *handle, struct inod= e *inode) EXT4_STATE_FC_COMMITTING); #endif prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE); - if (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) + if (ext4_test_inode_state(inode, EXT4_STATE_FC_COMMITTING)) { + /* + * We might sleep while waiting for the inode to commit. + * We shouldn't be holding i_data_sem when we go to sleep + * since the commit path may grab it while committing this + * inode. + */ + lockdep_assert_not_held(&ei->i_data_sem); schedule(); + } finish_wait(wq, &wait.wq_entry); } =20 --=20 2.52.0