linux/drivers/tty
David Daney 97c96c43d9 tty: vt: Fix soft lockup in fbcon cursor blink timer.
commit 1b45996d2e 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 <david.daney@cavium.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Ming Lei <ming.lei@canonical.com>
Acked-by: Scot Doyle <lkml14@scotdoyle.com>
Tested-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27 09:47:37 -07:00
..
hvc TTY/Serial driver patches for 4.4-rc1 2015-11-04 21:35:12 -08:00
ipwireless
serial QE-UART: add "fsl,t1040-ucc-uart" to of_device_id 2016-06-07 18:14:35 -07:00
vt tty: vt: Fix soft lockup in fbcon cursor blink timer. 2016-07-27 09:47:37 -07:00
amiserial.c
bfin_jtag_comm.c
cyclades.c tty: Remove ASYNC_CLOSING checks in open()/hangup() methods 2015-10-17 21:11:29 -07:00
ehv_bytechan.c
goldfish.c
isicom.c
Kconfig
Makefile
metag_da.c tty/metag_da: Avoid module_init/module_exit in non-modular code 2015-06-16 14:12:31 -04:00
mips_ejtag_fdc.c ttyFDC: Fix build problems due to use of module_{init,exit} 2015-10-17 21:29:21 -07:00
moxa.c
moxa.h
mxser.c
mxser.h
n_gsm.c TTY: n_gsm, fix false positive WARN_ON 2016-06-01 12:15:52 -07:00
n_hdlc.c Fix OpenSSH pty regression on close 2016-06-01 12:15:52 -07:00
n_r3964.c tty: r3964: Replace/remove bogus tty lock use 2015-10-17 21:11:29 -07:00
n_tracerouter.c n_tracerouter: stop including <asm-generic/bug> 2015-10-15 00:21:10 +02:00
n_tracesink.c n_tracesink: stop including <asm-generic/bug> 2015-10-15 00:21:11 +02:00
n_tracesink.h
n_tty.c Fix OpenSSH pty regression on close 2016-06-01 12:15:52 -07:00
nozomi.c
pty.c Fix OpenSSH pty regression on close 2016-06-01 12:15:52 -07:00
rocket_int.h
rocket.c tty: Remove tty_port::close_wait 2015-10-17 21:11:29 -07:00
rocket.h
synclink_gt.c tty: Remove ASYNC_CLOSING checks in open()/hangup() methods 2015-10-17 21:11:29 -07:00
synclink.c tty: synclink, fix indentation 2015-10-17 21:14:06 -07:00
synclinkmp.c tty: Remove ASYNC_CLOSING checks in open()/hangup() methods 2015-10-17 21:11:29 -07:00
sysrq.c drivers/tty: make sysrq.c slightly more explicitly non-modular 2015-10-04 17:27:56 +01:00
tty_audit.c tty: audit: Fix audit source 2015-11-20 16:19:54 -08:00
tty_buffer.c Fix OpenSSH pty regression on close 2016-06-01 12:15:52 -07:00
tty_io.c tty: Fix unsafe ldisc reference via ioctl(TIOCGETD) 2016-02-17 12:31:02 -08:00
tty_ioctl.c tty: Fix tty_send_xchar() lock order inversion 2015-11-20 16:19:54 -08:00
tty_ldisc.c tty: Fix direct use of tty buffer work 2015-11-20 16:19:54 -08:00
tty_ldsem.c
tty_mutex.c tty: Wait interruptibly for tty lock on reopen 2016-02-17 12:31:02 -08:00
tty_port.c tty: Abstract tty buffer work 2015-10-17 21:32:21 -07:00