diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2013-03-26 20:30:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-05 10:04:19 -0700 |
| commit | 86302600f82d715647154e18a96245642f1bf71e (patch) | |
| tree | b586260ea3bcd7a9e94fd328b53f0c12280efcb3 | |
| parent | 840d38a30d24c15fa29555f10a114feeff02cd80 (diff) | |
vt: synchronize_rcu() under spinlock is not nice...
commit e8cd81693bbbb15db57d3c9aa7dd90eda4842874 upstream.
vcs_poll_data_free() calls unregister_vt_notifier(), which calls
atomic_notifier_chain_unregister(), which calls synchronize_rcu().
Do it *after* we'd dropped ->f_lock.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/vt/vc_screen.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c index fa7268a93c06..6abb92c22c23 100644 --- a/drivers/tty/vt/vc_screen.c +++ b/drivers/tty/vt/vc_screen.c @@ -93,7 +93,7 @@ vcs_poll_data_free(struct vcs_poll_data *poll) static struct vcs_poll_data * vcs_poll_data_get(struct file *file) { - struct vcs_poll_data *poll = file->private_data; + struct vcs_poll_data *poll = file->private_data, *kill = NULL; if (poll) return poll; @@ -122,10 +122,12 @@ vcs_poll_data_get(struct file *file) file->private_data = poll; } else { /* someone else raced ahead of us */ - vcs_poll_data_free(poll); + kill = poll; poll = file->private_data; } spin_unlock(&file->f_lock); + if (kill) + vcs_poll_data_free(kill); return poll; } |