Paul Gortmaker f76a1cbed1 hvc: ensure hvc_init is only ever called once in hvc_console.c ... Commit 3e6c6f630a ("Delay creation of khcvd thread") moved the call of hvc_init from being a device_initcall into hvc_alloc, and used a non-null hvc_driver as indication of whether hvc_init had already been called. The problem with this is that hvc_driver is only assigned a value at the bottom of hvc_init, and so there is a window where multiple hvc_alloc calls can be in progress at the same time and hence try and call hvc_init multiple times. Previously the use of device_init guaranteed that hvc_init was only called once. This manifests itself as sporadic instances of two hvc_init calls racing each other, and with the loser of the race getting -EBUSY from tty_register_driver() and hence that virtual console fails: Couldn't register hvc console driver virtio-ports vport0p1: error -16 allocating hvc for port Here we add an atomic_t to guarantee we'll never run hvc_init twice. Cc: stable@vger.kernel.org # v2.6.24+ Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Fixes: 3e6c6f630a ("Delay creation of khcvd thread") Reported-by: Jim Somerville <Jim.Somerville@windriver.com> Tested-by: Jim Somerville <Jim.Somerville@windriver.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2014-02-13 10:41:47 -08:00
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hvc	hvc: ensure hvc_init is only ever called once in hvc_console.c	2014-02-13 10:41:47 -08:00
ipwireless	tty: delete non-required instances of include <linux/init.h>	2014-01-07 17:05:21 -08:00
serial	serial: sirf: move to use generic dma dt-binding to get dma channels	2014-02-13 10:36:25 -08:00
vt
amiserial.c	tty/amiserial: avoid interruptible_sleep_on	2014-01-07 17:05:21 -08:00
bfin_jtag_comm.c
cyclades.c
ehv_bytechan.c
goldfish.c	tty: delete non-required instances of include <linux/init.h>	2014-01-07 17:05:21 -08:00
isicom.c
Kconfig	drivers/tty: ehv_bytechan fails to build as a module	2014-01-09 17:52:12 -06:00
Makefile
metag_da.c
moxa.c
moxa.h
mxser.c
mxser.h
n_gsm.c	tty: n_gsm: Fix for modems with brk in modem status control	2014-02-07 08:40:54 -08:00
n_hdlc.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c	n_tty: Simplify input_available_p()	2014-02-13 10:18:48 -08:00
nozomi.c
pty.c
rocket_int.h
rocket.c
rocket.h
synclink_gt.c	tty: synclink: avoid sleep_on race	2014-01-07 17:05:21 -08:00
synclink.c	tty: synclink: avoid sleep_on race	2014-01-07 17:05:21 -08:00
synclinkmp.c	tty: synclink: avoid sleep_on race	2014-01-07 17:05:21 -08:00
sysrq.c
tty_audit.c	audit: convert all sessionid declaration to unsigned int	2014-01-13 22:31:46 -05:00
tty_buffer.c	tty: delete non-required instances of include <linux/init.h>	2014-01-07 17:05:21 -08:00
tty_io.c	tty: Set correct tty name in 'active' sysfs attribute	2014-02-07 08:40:54 -08:00
tty_ioctl.c
tty_ldisc.c	tty: delete non-required instances of include <linux/init.h>	2014-01-07 17:05:21 -08:00
tty_ldsem.c
tty_mutex.c
tty_port.c	tty: delete non-required instances of include <linux/init.h>	2014-01-07 17:05:21 -08:00