diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2010-06-01 22:53:06 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-08-10 13:47:43 -0700 |
| commit | 60af22d2ed490554cc92c8d0fed0b5b9cf687568 (patch) | |
| tree | 6c9d1b2d9b5c409dc6a38f26ed5b7ec0f37a041a /drivers/char/selection.c | |
| parent | be1bc2889a4db4961ef69f47fb471ecae9f23ade (diff) | |
tty: reorder ldisc locking
We need to release the BTM in paste_selection() when
sleeping in tty_ldisc_ref_wait to avoid deadlocks
with tty_ldisc_enable.
In tty_set_ldisc, we now always grab the BTM before
taking the ldisc_mutex in order to avoid AB-BA
deadlocks between the two.
tty_ldisc_halt potentially blocks on a workqueue
function that takes the BTM, so we must release
the BTM before calling it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/char/selection.c')
| -rw-r--r-- | drivers/char/selection.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/char/selection.c b/drivers/char/selection.c index 85211a3a5811..75889cd9375f 100644 --- a/drivers/char/selection.c +++ b/drivers/char/selection.c @@ -319,8 +319,13 @@ int paste_selection(struct tty_struct *tty) poke_blanked_console(); release_console_sem(); - ld = tty_ldisc_ref_wait(tty); - + ld = tty_ldisc_ref(tty); + if (!ld) { + tty_unlock(); + ld = tty_ldisc_ref_wait(tty); + tty_lock(); + } + add_wait_queue(&vc->paste_wait, &wait); while (sel_buffer && sel_buffer_lth > pasted) { set_current_state(TASK_INTERRUPTIBLE); |