This is a note to let you know that I've just added the patch titled
ocfs2: should wait dio before inode lock in ocfs2_setattr()
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ocfs2-should-wait-dio-before-inode-lock-in-ocfs2_setattr.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 28f5a8a7c033cbf3e32277f4cc9c6afd74f05300 Mon Sep 17 00:00:00 2001
From: alex chen <alex.chen@xxxxxxxxxx>
Date: Wed, 15 Nov 2017 17:31:40 -0800
Subject: ocfs2: should wait dio before inode lock in ocfs2_setattr()
From: alex chen <alex.chen@xxxxxxxxxx>
commit 28f5a8a7c033cbf3e32277f4cc9c6afd74f05300 upstream.
we should wait dio requests to finish before inode lock in
ocfs2_setattr(), otherwise the following deadlock will happen:
process 1 process 2 process 3
truncate file 'A' end_io of writing file 'A' receiving the bast messages
ocfs2_setattr
ocfs2_inode_lock_tracker
ocfs2_inode_lock_full
inode_dio_wait
__inode_dio_wait
-->waiting for all dio
requests finish
dlm_proxy_ast_handler
dlm_do_local_bast
ocfs2_blocking_ast
ocfs2_generic_handle_bast
set OCFS2_LOCK_BLOCKED flag
dio_end_io
dio_bio_end_aio
dio_complete
ocfs2_dio_end_io
ocfs2_dio_end_io_write
ocfs2_inode_lock
__ocfs2_cluster_lock
ocfs2_wait_for_mask
-->waiting for OCFS2_LOCK_BLOCKED
flag to be cleared, that is waiting
for 'process 1' unlocking the inode lock
inode_dio_end
-->here dec the i_dio_count, but will never
be called, so a deadlock happened.
Link: http://lkml.kernel.org/r/59F81636.70508@xxxxxxxxxx
Signed-off-by: Alex Chen <alex.chen@xxxxxxxxxx>
Reviewed-by: Jun Piao <piaojun@xxxxxxxxxx>
Reviewed-by: Joseph Qi <jiangqi903@xxxxxxxxx>
Acked-by: Changwei Ge <ge.changwei@xxxxxxx>
Cc: Mark Fasheh <mfasheh@xxxxxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ocfs2/file.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1166,6 +1166,13 @@ int ocfs2_setattr(struct dentry *dentry,
}
size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
if (size_change) {
+ /*
+ * Here we should wait dio to finish before inode lock
+ * to avoid a deadlock between ocfs2_setattr() and
+ * ocfs2_dio_end_io_write()
+ */
+ inode_dio_wait(inode);
+
status = ocfs2_rw_lock(inode, 1);
if (status < 0) {
mlog_errno(status);
@@ -1186,8 +1193,6 @@ int ocfs2_setattr(struct dentry *dentry,
if (status)
goto bail_unlock;
- inode_dio_wait(inode);
-
if (i_size_read(inode) >= attr->ia_size) {
if (ocfs2_should_order_data(inode)) {
status = ocfs2_begin_ordered_truncate(inode,
Patches currently in stable-queue which might be from alex.chen@xxxxxxxxxx are
queue-4.4/ocfs2-should-wait-dio-before-inode-lock-in-ocfs2_setattr.patch