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alex chen
44ec0aecc7
commit 28f5a8a7c0 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@huawei.com
Signed-off-by: Alex Chen <alex.chen@huawei.com>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Acked-by: Changwei Ge <ge.changwei@h3c.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.