linux-stable.git/drivers/usb/serial/console.c, branch linux-4.8.y

tty: Replace ASYNC_INITIALIZED bit and update atomically

2016-04-30T16:26:55+00:00

Replace ASYNC_INITIALIZED bit in the tty_port::flags field with
TTY_PORT_INITIALIZED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_initialized() and tty_port_initialized() to abstract
atomic bit ops.

Note: the transforms for test_and_set_bit() and test_and_clear_bit()
are unnecessary as the state transitions are already mutually exclusive;
the tty lock prevents concurrent open/close/hangup.

Signed-off-by: Peter Hurley 
Signed-off-by: Greg Kroah-Hartman

tty: Fix tty_init_termios() declaration

2016-01-27T22:28:20+00:00

tty_init_termios() never returns an error; re-declare as void. Remove
unnecessary error handling from callers. Remove extern declarations
of tty_free_termios() and free_tty_struct() and re-declare in file
scope.

Signed-off-by: Peter Hurley 
Acked-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

USB: console: add dummy __module_get

2015-02-26T16:06:39+00:00

Add call to __module_get when initialising the fake tty in
usb_console_setup to match the module_put in release_one_tty.

Note that the tty-driver (i.e. usb-serial core) must be compiled-in to
enable the usb console so the __module_get is essentially a noop as
driver->owner will be null.

Reported-by: Ben Hutchings 
Signed-off-by: Johan Hovold

USB: console: fix potential use after free

2015-01-10T11:48:21+00:00

Use tty kref to release the fake tty in usb_console_setup to avoid use
after free if the underlying serial driver has acquired a reference.

Note that using the tty destructor release_one_tty requires some more
state to be initialised.

Fixes: 4a90f09b20f4 ("tty: usb-serial krefs")
Cc: stable 
Signed-off-by: Johan Hovold

USB: console: fix uninitialised ldisc semaphore

2015-01-10T11:48:15+00:00

The USB console currently allocates a temporary fake tty which is used
to pass terminal settings to the underlying serial driver.

The tty struct is not fully initialised, something which can lead to a
lockdep warning (or worse) if a serial driver tries to acquire a
line-discipline reference:

	usbserial: USB Serial support registered for pl2303
	pl2303 1-2.1:1.0: pl2303 converter detected
	usb 1-2.1: pl2303 converter now attached to ttyUSB0
	INFO: trying to register non-static key.
	the code is fine but needs lockdep annotation.
	turning off the locking correctness validator.
	CPU: 0 PID: 68 Comm: udevd Tainted: G        W      3.18.0-rc5 #10
	[] (unwind_backtrace) from [] (show_stack+0x20/0x24)
	[] (show_stack) from [] (dump_stack+0x24/0x28)
	[] (dump_stack) from [] (__lock_acquire+0x1e50/0x2004)
	[] (__lock_acquire) from [] (lock_acquire+0xe4/0x18c)
	[] (lock_acquire) from [] (ldsem_down_read_trylock+0x78/0x90)
	[] (ldsem_down_read_trylock) from [] (tty_ldisc_ref+0x24/0x58)
	[] (tty_ldisc_ref) from [] (usb_serial_handle_dcd_change+0x48/0xe8)
	[] (usb_serial_handle_dcd_change) from [] (pl2303_read_int_callback+0x210/0x220 [pl2303])
	[] (pl2303_read_int_callback [pl2303]) from [] (__usb_hcd_giveback_urb+0x80/0x140)
	[] (__usb_hcd_giveback_urb) from [] (usb_giveback_urb_bh+0x98/0xd4)
	[] (usb_giveback_urb_bh) from [] (tasklet_hi_action+0x9c/0x108)
	[] (tasklet_hi_action) from [] (__do_softirq+0x148/0x42c)
	[] (__do_softirq) from [] (irq_exit+0xd8/0x114)
	[] (irq_exit) from [] (__handle_domain_irq+0x84/0xdc)
	[] (__handle_domain_irq) from [] (omap_intc_handle_irq+0xd8/0xe0)
	[] (omap_intc_handle_irq) from [] (__irq_svc+0x44/0x7c)
	Exception stack(0xdf4e7f08 to 0xdf4e7f50)
	7f00:                   debc0b80 df4e7f5c 00000000 00000000 debc0b80 be8da96c
	7f20: 00000000 00000128 c000fc84 df4e6000 00000000 df4e7f94 00000004 df4e7f50
	7f40: c038ebc0 c038d74c 600f0013 ffffffff
	[] (__irq_svc) from [] (___sys_sendmsg.part.29+0x0/0x2e0)
	[] (___sys_sendmsg.part.29) from [] (SyS_sendmsg+0x18/0x1c)
	[] (SyS_sendmsg) from [] (ret_fast_syscall+0x0/0x48)
	console [ttyUSB0] enabled

Fixes: 36697529b5bb ("tty: Replace ldisc locking with ldisc_sem")
Cc: stable 
Signed-off-by: Johan Hovold

usb: delete non-required instances of include

2014-01-08T23:01:39+00:00

None of these files are actually using any __init type directives
and hence don't need to include .  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

Signed-off-by: Paul Gortmaker 
Signed-off-by: Greg Kroah-Hartman

USB: serial: remove redundant OOM messages

2014-01-03T20:31:46+00:00

Remove redundant error messages on allocation failures, which have
already been logged.

Cc: Joe Perches 
Signed-off-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

USB: console: remove unnecessary operations test

2013-07-23T23:24:32+00:00

Remove unnecessary tests for open and write operations as these are set
to the generic implementations by usb-serial core if left unset by a
subdriver.

Signed-off-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

USB: console: use dev_dbg

2013-07-23T23:24:32+00:00

Use dev_dbg for debugging.

Signed-off-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman

USB: serial: make minor allocation dynamic

2013-06-17T20:30:02+00:00

This moves the allocation of minor device numbers from a static array to
be dynamic, using the idr interface.  This means that you could
potentially get "gaps" in a minor number range for a single USB serial
device with multiple ports, but all should still work properly.

We remove the 'minor' field from the usb_serial structure, as it no
longer makes any sense for it (use the field in the usb_serial_port
structure if you really want to know this number), and take the fact
that we were overloading a number in this field to determine if we had
initialized the minor numbers or not, and just use a flag variable
instead.

Note, we still have the limitation of 255 USB to serial devices in the
system, as that is all we are registering with the TTY layer at this
point in time.

Tested-by: Tobias Winter 
Reviewed-by: Johan Hovold 
Signed-off-by: Greg Kroah-Hartman