----- Original Message ----- > From: Tim Smith <tim.sm...@citrix.com> > > Flushing the workqueue can cause operations to happen which might > call gfs2_log_reserve(), or get stuck waiting for locks taken by such > operations. gfs2_log_reserve() can io_schedule(). If this happens, it > will never wake because the only thing which can wake it is gfs2_logd() > which was already stopped. > > This causes umount of a gfs2 filesystem to wedge permanently if, for > example, the umount immediately follows a large delete operation. > > When this occured, the following stack trace was obtained from the > umount command > > [<ffffffff81087968>] flush_workqueue+0x1c8/0x520 > [<ffffffffa0666e29>] gfs2_make_fs_ro+0x69/0x160 [gfs2] > [<ffffffffa0667279>] gfs2_put_super+0xa9/0x1c0 [gfs2] > [<ffffffff811b7edf>] generic_shutdown_super+0x6f/0x100 > [<ffffffff811b7ff7>] kill_block_super+0x27/0x70 > [<ffffffffa0656a71>] gfs2_kill_sb+0x71/0x80 [gfs2] > [<ffffffff811b792b>] deactivate_locked_super+0x3b/0x70 > [<ffffffff811b79b9>] deactivate_super+0x59/0x60 > [<ffffffff811d2998>] cleanup_mnt+0x58/0x80 > [<ffffffff811d2a12>] __cleanup_mnt+0x12/0x20 > [<ffffffff8108c87d>] task_work_run+0x7d/0xa0 > [<ffffffff8106d7d9>] exit_to_usermode_loop+0x73/0x98 > [<ffffffff81003961>] syscall_return_slowpath+0x41/0x50 > [<ffffffff815a594c>] int_ret_from_sys_call+0x25/0x8f > [<ffffffffffffffff>] 0xffffffffffffffff > > Signed-off-by: Tim Smith <tim.sm...@citrix.com> > Signed-off-by: Mark Syms <mark.s...@citrix.com> > --- Hi Mark, Tim, and all,
I pushed patch 2/2 upstream. For now I'll hold off on 1/2 but keep it on my queue, pending our investigation. https://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git/commit/fs/gfs2?h=for-next&id=b7f5a2cd27b76e96fdc6d77b060dfdd877c9d0a9 Regards, Bob Peterson
