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 70F002FDC5C; Tue, 26 Aug 2025 14:45:10 +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=1756219510; cv=none; b=k77MhYPWPky7OzVamZt1WSGvqaxMLeeuBIBN6iwnMx5y2EpJ2P7mRIH0TdFJDDfW5O1VN8xW4CBAQV5Td5biCBt5+POMhQTvO57Sjiensttj0queK2hkjqlkajPkCaqU2lV4U0nNyVS0px1H7AHP/d2NQWETXt6NqA0QRlvdEUI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756219510; c=relaxed/simple; bh=aFBnRvvV98YqgdZJRGGH8pIlFVwyIeHNlLl3Ci6HqZc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=u0YFTJH60yLXTVrKWyIlLIbqZFwhJoCX2Qy6pCqV+Ad0PYDFWl9Jaqj7vLgCXZVzxNWoo5aX4I7vNFj+xw/O3sjyIb89CbgE3n9+Eqkmr/7+n9VySyNBWp6ugiQQ6/KXsJM/XCc7Dh4fNOTiC1HWtoOvEikkCkI5shhyQrsrZyE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NSXWGexB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="NSXWGexB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06AD0C4CEF1; Tue, 26 Aug 2025 14:45:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756219510; bh=aFBnRvvV98YqgdZJRGGH8pIlFVwyIeHNlLl3Ci6HqZc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NSXWGexBhA4MVd6kQbL9gGHzitiUR2DtDm1wG6PeqE8ojByu1g3ktVgqmiYfZpolT AKrvx8EN0gG7q3fPPZ7aiMfqSmIKGn/4rLQIrJZq2dcfsBZbtI8+4dIuyfH2PVEKQm YvRDuXYS1eRG77t8+llaNvRIGpOHwmIo0SerTivQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Trond Myklebust , Chanho Min , Sasha Levin Subject: [PATCH 5.4 392/403] NFS: Fix up commit deadlocks Date: Tue, 26 Aug 2025 13:11:58 +0200 Message-ID: <20250826110917.863347852@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110905.607690791@linuxfoundation.org> References: <20250826110905.607690791@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Trond Myklebust commit 133a48abf6ecc535d7eddc6da1c3e4c972445882 upstream. If O_DIRECT bumps the commit_info rpcs_out field, then that could lead to fsync() hangs. The fix is to ensure that O_DIRECT calls nfs_commit_end(). Fixes: 723c921e7dfc ("sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API") Signed-off-by: Trond Myklebust Signed-off-by: Chanho Min Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/nfs/direct.c | 2 +- fs/nfs/write.c | 9 ++++++--- include/linux/nfs_fs.h | 1 + 3 files changed, 8 insertions(+), 4 deletions(-) --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -700,7 +700,7 @@ static void nfs_direct_commit_complete(s nfs_unlock_and_release_request(req); } - if (atomic_dec_and_test(&cinfo.mds->rpcs_out)) + if (nfs_commit_end(cinfo.mds)) nfs_direct_write_complete(dreq); } --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -1658,10 +1658,13 @@ static void nfs_commit_begin(struct nfs_ atomic_inc(&cinfo->rpcs_out); } -static void nfs_commit_end(struct nfs_mds_commit_info *cinfo) +bool nfs_commit_end(struct nfs_mds_commit_info *cinfo) { - if (atomic_dec_and_test(&cinfo->rpcs_out)) + if (atomic_dec_and_test(&cinfo->rpcs_out)) { wake_up_var(&cinfo->rpcs_out); + return true; + } + return false; } void nfs_commitdata_release(struct nfs_commit_data *data) @@ -1756,6 +1759,7 @@ void nfs_init_commit(struct nfs_commit_d data->res.fattr = &data->fattr; data->res.verf = &data->verf; nfs_fattr_init(&data->fattr); + nfs_commit_begin(cinfo->mds); } EXPORT_SYMBOL_GPL(nfs_init_commit); @@ -1801,7 +1805,6 @@ nfs_commit_list(struct inode *inode, str /* Set up the argument struct */ nfs_init_commit(data, head, NULL, cinfo); - atomic_inc(&cinfo->mds->rpcs_out); return nfs_initiate_commit(NFS_CLIENT(inode), data, NFS_PROTO(inode), data->mds_ops, how, 0); } --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -549,6 +549,7 @@ extern int nfs_wb_page_cancel(struct ino extern int nfs_commit_inode(struct inode *, int); extern struct nfs_commit_data *nfs_commitdata_alloc(bool never_fail); extern void nfs_commit_free(struct nfs_commit_data *data); +bool nfs_commit_end(struct nfs_mds_commit_info *cinfo); static inline int nfs_have_writebacks(struct inode *inode)