4.6-stable review patch. If anyone has any objections, please let me know.
------------------ From: David Daney <[email protected]> commit 1b45996d2ebf9680ccd0db875fc668aa025f40fd upstream. We are getting somewhat random soft lockups with this signature: [ 86.992215] [<fffffc00080935e0>] el1_irq+0xa0/0x10c [ 86.997082] [<fffffc000841822c>] cursor_timer_handler+0x30/0x54 [ 87.002991] [<fffffc000810ec44>] call_timer_fn+0x54/0x1a8 [ 87.008378] [<fffffc000810ef88>] run_timer_softirq+0x1c4/0x2bc [ 87.014200] [<fffffc000809077c>] __do_softirq+0x114/0x344 [ 87.019590] [<fffffc00080af45c>] irq_exit+0x74/0x98 [ 87.024458] [<fffffc00080fac20>] __handle_domain_irq+0x98/0xfc [ 87.030278] [<fffffc000809056c>] gic_handle_irq+0x94/0x190 This is caused by the vt visual_init() function calling into fbcon_init() with a vc_cur_blink_ms value of zero. This is a transient condition, as it is later set to a non-zero value. But, if the timer happens to expire while the blink rate is zero, it goes into an endless loop, and we get soft lockup. The fix is to initialize vc_cur_blink_ms before calling the con_init() function. Signed-off-by: David Daney <[email protected]> Acked-by: Pavel Machek <[email protected]> Tested-by: Ming Lei <[email protected]> Acked-by: Scot Doyle <[email protected]> Tested-by: Henrique de Moraes Holschuh <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/tty/vt/vt.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -750,6 +750,7 @@ static void visual_init(struct vc_data * vc->vc_complement_mask = 0; vc->vc_can_do_color = 0; vc->vc_panic_force_write = false; + vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS; vc->vc_sw->con_init(vc, init); if (!vc->vc_complement_mask) vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
