| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.14 13/71] orangefs: fix deadlock; do not write i_size in read_iter | Date | Mon, 29 Jan 2018 13:56:41 +0100 |
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4.14-stable review patch. If anyone has any objections, please let me know.
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From: Martin Brandenburg <martin@omnibond.com>
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 <martin@omnibond.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Mike Marshall <hubcap@omnibond.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- 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); @@ -486,9 +486,6 @@ 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) { @@ -502,7 +499,7 @@ 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 @@ -566,17 +566,6 @@ 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;
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