From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:33438 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753796AbeA2ULw (ORCPT ); Mon, 29 Jan 2018 15:11:52 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Martin Brandenburg , Al Viro , Mike Marshall , Linus Torvalds Subject: [PATCH 4.9 29/66] orangefs: fix deadlock; do not write i_size in read_iter Date: Mon, 29 Jan 2018 13:56:53 +0100 Message-Id: <20180129123841.360857019@linuxfoundation.org> In-Reply-To: <20180129123839.842860149@linuxfoundation.org> References: <20180129123839.842860149@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martin Brandenburg commit 6793f1c450b1533a5e9c2493490de771d38b24f9 upstream. After do_readv_writev, the inode cache is invalidated anyway, so i_size will never be read. It will be fetched from the server which will also know about updates from other machines. Fixes deadlock on 32-bit SMP. See https://marc.info/?l=linux-fsdevel&m=151268557427760&w=2 Signed-off-by: Martin Brandenburg Cc: Al Viro Cc: Mike Marshall Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/orangefs/file.c | 7 ++----- fs/orangefs/orangefs-kernel.h | 11 ----------- 2 files changed, 2 insertions(+), 16 deletions(-) --- a/fs/orangefs/file.c +++ b/fs/orangefs/file.c @@ -446,7 +446,7 @@ ssize_t orangefs_inode_read(struct inode static ssize_t orangefs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) { struct file *file = iocb->ki_filp; - loff_t pos = *(&iocb->ki_pos); + loff_t pos = iocb->ki_pos; ssize_t rc = 0; BUG_ON(iocb->private); @@ -485,9 +485,6 @@ static ssize_t orangefs_file_write_iter( } } - if (file->f_pos > i_size_read(file->f_mapping->host)) - orangefs_i_size_write(file->f_mapping->host, file->f_pos); - rc = generic_write_checks(iocb, iter); if (rc <= 0) { @@ -501,7 +498,7 @@ static ssize_t orangefs_file_write_iter( * pos to the end of the file, so we will wait till now to set * pos... */ - pos = *(&iocb->ki_pos); + pos = iocb->ki_pos; rc = do_readv_writev(ORANGEFS_IO_WRITE, file, --- a/fs/orangefs/orangefs-kernel.h +++ b/fs/orangefs/orangefs-kernel.h @@ -570,17 +570,6 @@ do { \ sys_attr.mask = ORANGEFS_ATTR_SYS_ALL_SETABLE; \ } while (0) -static inline void orangefs_i_size_write(struct inode *inode, loff_t i_size) -{ -#if BITS_PER_LONG == 32 && defined(CONFIG_SMP) - inode_lock(inode); -#endif - i_size_write(inode, i_size); -#if BITS_PER_LONG == 32 && defined(CONFIG_SMP) - inode_unlock(inode); -#endif -} - static inline void orangefs_set_timeout(struct dentry *dentry) { unsigned long time = jiffies + orangefs_dcache_timeout_msecs*HZ/1000;