Most tty drivers may block while opening a device.
Since this possibly depends on another thread
closing it first and both threads may need the BTM,
we need to release it here.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The tty locking now follows the rules for mutexes, so
we can replace the BKL usage with a new subsystem
wide mutex.

Using a regular mutex here will change the behaviour
when blocked on the BTM from spinning to sleeping,
but that should not be visible to the user.

Using the mutex also means that all the BTM is now
covered by lockdep.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This changes all remaining users of tty_lock_nested
to be non-recursive, which lets us kill this function.
As a consequence, we won't need to keep the lock count
any more, which allows more simplifications later.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Some wait_until_sent versions require the big
tty mutex, others don't and some callers of
wait_until_sent already hold it while other don't.
That leads to recursive use of the BTM in these
functions, which we're trying to get rid of.

This turns all cleans up the locking there so
that the driver's wait_until_sent function
never takes the BTM itself if it is already
called with that lock held.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

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: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Calling wait_event_interruptible implicitly
releases the BKL when it sleeps, but we need
to do this explcitly when we have converted
it to a mutex.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

tty_mutex is never taken with the BTM held, except for
two corner cases that are worked around here.
We give up the BTM before calling tty_release() in the
error path of tty_open().
Similarly, we reorder the locking in ptmx_open()
to get tty_mutex before the BTM.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

As a preparation for replacing the big kernel lock
in the TTY layer, wrap all the callers in new
macros tty_lock, tty_lock_nested and tty_unlock.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This takes all the tty references through the expected interface points so
we can refcount them.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The vt layer isn't safely handling reference counts to tty object on the input
side. Add a tty port structure to the vt layer in order to implement this using
the standard helpers.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The virtual console layer uses the BKL for various things that don't really
need it. Clean them out.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Use the port mutex and port lock to fix the various races. The locking
still isn't totally consistent but its better than before. Wants switching
to the port helpers.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Use the port mutex instead
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The lock is no longer needed for wait until sent paths so this can go
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Use the port mutext for config setting, the rest is locked sufficiently
anyway that the BKL makes no odds.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We don't need it while waiting and we can lock the ioctls using the port
mutex. While at it eliminate use of the hangup mutex and switch to the port
mutex.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We can use the port mutex for this and also for the hangup path so removing
the problematic use of the hangup mutex in this driver. Fix up the locking
on the various port flags while we are at it.

Ultimately this driver needs to be using tty_port_ helpers which would sort
this out far better.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

As with the others we can use the port mutex to get the needed locking
properties and fix the race with open.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The riscom8 board uses lock_kernel to protect bits of the port setting
ioctl logic. We can use the port mutex for this as the logic is internal
and will also lock set versus open (a locking property that has been lost
somewhere along the way)
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This lets us avoid problems with races on the flag changes
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Remove unneeded tty layer lock kernel bits. Relock the needed bits using the
port mutex. The istallion still has brd state races but those are not new
or introduced by the removal of the lock_kernel logic.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Jesse's initial patch commit said:

"At panic time (i.e.  when oops_in_progress is set) we should try a bit
harder to update the screen and make sure output gets to the VT, since
some drivers are capable of flipping back to it.

So make sure we try to unblank and update the display if called from a
panic context."

I've enhanced this to add a flag to the vc that console layer can set to
indicate they want this behaviour to occur.  This also adds support to
fbcon for that flag and adds an fb flag for drivers to indicate they want
to use the support.  It enables this for KMS drivers.
Signed-off-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: NJames Simmons <jsimmons@infradead.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch is against the 2.6.34 source.

Paraphrased from the 1989 BSD patch by David Borman @ cray.com:

     These are the changes needed for the kernel to support
     LINEMODE in the server.

     There is a new bit in the termios local flag word, EXTPROC.
     When this bit is set, several aspects of the terminal driver
     are disabled.  Input line editing, character echo, and mapping
     of signals are all disabled.  This allows the telnetd to turn
     off these functions when in linemode, but still keep track of
     what state the user wants the terminal to be in.

     New ioctl:
         TIOCSIG         Generate a signal to processes in the
                         current process group of the pty.

     There is a new mode for packet driver, the TIOCPKT_IOCTL bit.
     When packet mode is turned on in the pty, and the EXTPROC bit
     is set, then whenever the state of the pty is changed, the
     next read on the master side of the pty will have the TIOCPKT_IOCTL
     bit set.  This allows the process on the server side of the pty
     to know when the state of the terminal has changed; it can then
     issue the appropriate ioctl to retrieve the new state.

Since the original BSD patches accompanied the source code for telnet
I've left that reference here, but obviously the feature is useful for
any remote terminal protocol, including ssh.

The corresponding feature has existed in the BSD tty driver since 1989.
For historical reference, a good copy of the relevant files can be found
here:

http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741Signed-off-by: NHoward Chu <hyc@symas.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NAndy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/char/n_gsm.c: linux/timer.h is included more than once.
Signed-off-by: NAndrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

According include/linux/console_struct.h,vc_scr_end is unsigned long.

struct vc_data {
    unsigned short  vc_num;         /* Console number */
    unsigned int    vc_cols;        /* [#] Console size */
    unsigned int    vc_rows;
    unsigned int    vc_size_row;        /* Bytes per row */
    unsigned int    vc_scan_lines;      /* # of scan lines */
    unsigned long   vc_origin;      /* [!] Start of real screen */
    unsigned long   vc_scr_end;     /* [!] End of real screen */
    unsigned long   vc_visible_origin;  /* [!] Top of visible window */
    unsigned int    vc_top, vc_bottom;  /* Scrolling region */
    const struct consw *vc_sw;
    unsigned short  *vc_screenbuf;
...
}
Signed-off-by: Nqiaochong <qiaochong@loongson.cn>
Cc: Greg KH <greg@kroah.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kernel will die on some platform when switch from vga mode to framebuffer
mode.  The reason of this bug is that bind_con_driver reset vc->vc_origin
to (unsigned long)vc->vc_screenbuf.

On vgacon vc->vc_origin is not releated to vc->vc_screenbuf,if set
vc->vc_origin to vc->vc_screenbuf,kernel will die on vc_do_resize.

static int vc_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
        struct vc_data *vc, unsigned int cols, unsigned int lines)
{
    unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
    unsigned int old_cols, old_rows, old_row_size, old_screen_size;
    unsigned int new_cols, new_rows, new_row_size, new_screen_size;
    unsigned int end, user;
...
        end = (old_rows > new_rows) ? old_origin +
            (old_row_size * new_rows) :
            vc->vc_scr_end;

...
/*
here for a test from vgacon to framebuffer:
old_origin=0x810814a0,end=0xb00b8fa0,vc->vc_origin=0x810814a0
the code bellow will copy memory from 0x810814a0 to 0xb00b8fa0,
this will cover kernel code,kernel died here.
*/

    while (old_origin < end) {

        scr_memcpyw((unsigned short *) new_origin,
                (unsigned short *) old_origin, rlth);
        if (rrem)
            scr_memsetw((void *)(new_origin + rlth),
                    vc->vc_video_erase_char, rrem);
        old_origin += old_row_size;
        new_origin += new_row_size;
    }

...
}

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Nqiaochong <qiaochong@loongson.cn>
Cc: Greg KH <greg@kroah.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

misc_deregister() returns an error only when it attempts to unregister
the device that is not registered. This is the driver's bug.

Most of the drivers don't check the return value of misc_deregister().
(It is not bad thing because most of kernel *_unregister() API always
succeed and do not return value)

So it is better to indicate the error by WARN_ON() in misc_deregister().
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After the commit that changed ipmi_si detecting sequence from SMBIOS/ACPI
to ACPI/SMBIOS,

| commit 754d4531
| Author: Matthew Garrett <mjg@redhat.com>
| Date:   Wed May 26 14:43:47 2010 -0700
|
|    ipmi: change device discovery order
|
|    The ipmi spec provides an ordering for si discovery.  Change the driver to
|    match, with the exception of preferring smbios to SPMI as HPs (at least)
|    contain accurate information in the former but not the latter.

ipmi_si can not be initialized.

[  138.799739] calling  init_ipmi_devintf+0x0/0x109 @ 1
[  138.805050] ipmi device interface
[  138.818131] initcall init_ipmi_devintf+0x0/0x109 returned 0 after 12797 usecs
[  138.822998] calling  init_ipmi_si+0x0/0xa90 @ 1
[  138.840276] IPMI System Interface driver.
[  138.846137] ipmi_si: probing via ACPI
[  138.849225] ipmi_si 00:09: [io  0x0ca2] regsize 1 spacing 1 irq 0
[  138.864438] ipmi_si: Adding ACPI-specified kcs state machine
[  138.870893] ipmi_si: probing via SMBIOS
[  138.880945] ipmi_si: Adding SMBIOS-specified kcs state machineipmi_si: duplicate interface
[  138.896511] ipmi_si: probing via SPMI
[  138.899861] ipmi_si: Adding SPMI-specified kcs state machineipmi_si: duplicate interface
[  138.917095] ipmi_si: Trying ACPI-specified kcs state machine at i/o address 0xca2, slave address 0x0, irq 0
[  138.928658] ipmi_si: Interface detection failed
[  138.953411] initcall init_ipmi_si+0x0/0xa90 returned 0 after 110847 usecs

in smbios has
DMI/SMBIOS
Handle 0x00C5, DMI type 38, 18 bytes
IPMI Device Information
        Interface Type: KCS (Keyboard Control Style)
        Specification Version: 2.0
        I2C Slave Address: 0x00
        NV Storage Device: Not Present
        Base Address: 0x0000000000000CA2 (I/O)
        Register Spacing: 32-bit Boundaries
in DSDT has
                    Device (BMC)
                    {

                        Name (_HID, EisaId ("IPI0001"))
                        Method (_STA, 0, NotSerialized)
                        {
                            If (LEqual (OSN, Zero))
                            {
                                Return (Zero)
                            }

                            Return (0x0F)
                        }

                        Name (_STR, Unicode ("IPMI_KCS"))
                        Name (_UID, Zero)
                        Name (_CRS, ResourceTemplate ()
                        {
                            IO (Decode16,
                                0x0CA2,             // Range Minimum
                                0x0CA2,             // Range Maximum
                                0x00,               // Alignment
                                0x01,               // Length
                                )
                            IO (Decode16,
                                0x0CA6,             // Range Minimum
                                0x0CA6,             // Range Maximum
                                0x00,               // Alignment
                                0x01,               // Length
                                )
                        })
                        Method (_IFT, 0, NotSerialized)
                        {
                            Return (One)
                        }

                        Method (_SRV, 0, NotSerialized)
                        {
                            Return (0x0200)
                        }
                    }

so the reg spacing should be 4 instead of 1.

Try to calculate regspacing for this kind of system.

Observed on a Sun Fire X4800.  Other OSes work and pass certification.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Acked-by: NMatthew Garrett <mjg@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Myron Stowe <myron.stowe@hp.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make /dev/console get initialised before any initialisation routine that
invokes modprobe because if modprobe fails, it's going to want to open
/dev/console, presumably to write an error message to.

The problem with that is that if the /dev/console driver is not yet
initialised, the chardev handler will call request_module() to invoke
modprobe, which will fail, because we never compile /dev/console as a
module.

This will lead to a modprobe loop, showing the following in the kernel
log:

	request_module: runaway loop modprobe char-major-5-1
	request_module: runaway loop modprobe char-major-5-1
	request_module: runaway loop modprobe char-major-5-1
	request_module: runaway loop modprobe char-major-5-1
	request_module: runaway loop modprobe char-major-5-1

This can happen, for example, when the built in md5 module can't find
the built in cryptomgr module (because the latter fails to initialise).
The md5 module comes before the call to tty_init(), presumably because
'crypto' comes before 'drivers' alphabetically.

Fix this by calling tty_init() from chrdev_init().
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The kernel console interface stores the number of lines it is
configured to use. The kdb debugger can greatly benefit by knowing how
many lines there are on the console for the pager functionality
without having the end user compile in the setting or have to
repeatedly change it at run time.
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
CC: David Airlie <airlied@linux.ie>
CC: Andrew Morton <akpm@linux-foundation.org>

These functions allow the kernel debugger to save and restore the
state of the system console.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
CC: David Airlie <airlied@linux.ie>
CC: Andrew Morton <akpm@linux-foundation.org>

The PPP channel ops structure should be const.
Cleanup the declarations to use standard C99 format.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IRQ and resource[] may not have correct values until
after PCI hotplug setup occurs at pci_enable_device() time.

The semantic match that finds this problem is as follows:

// <smpl>
@@
identifier x;
identifier request ~= "pci_request.*|pci_resource.*";
@@

(
* x->irq
|
* x->resource
|
* request(x, ...)
)
 ...
*pci_enable_device(x)
// </smpl>
Signed-off-by: NKulikov Vasiliy <segooon@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

IRQ and resource[] may not have correct values until
after PCI hotplug setup occurs at pci_enable_device() time.

The semantic match that finds this problem is as follows:

// <smpl>
@@
identifier x;
identifier request ~= "pci_request.*|pci_resource.*";
@@

(
* x->irq
|
* x->resource
|
* request(x, ...)
)
 ...
*pci_enable_device(x)
// </smpl>
Signed-off-by: NKulikov Vasiliy <segooon@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Use struct resource * also for iomem resources.

CC: linux-mtd@lists.infradead.org
CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Page already had to be set to 0; Offset can easily be passed as
parameter to pcmcia_map_mem_page.

CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: linux-ide@vger.kernel.org
CC: linux-usb@vger.kernel.org
CC: laforge@gnumonks.org
CC: linux-mtd@lists.infradead.org
CC: linux-bluetooth@vger.kernel.org
CC: alsa-devel@alsa-project.org
CC: linux-serial@vger.kernel.org
CC: Michael Buesch <mb@bu3sch.de>
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Instead of io_req_t, drivers are now requested to fill out
struct pcmcia_device *p_dev->resource[0,1] for up to two ioport
ranges. After a call to pcmcia_request_io(), the ports found there
are reserved, after calling pcmcia_request_configuration(), they may
be used.

CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: linux-ide@vger.kernel.org
CC: linux-usb@vger.kernel.org
CC: laforge@gnumonks.org
CC: linux-mtd@lists.infradead.org
CC: alsa-devel@alsa-project.org
CC: linux-serial@vger.kernel.org
CC: Michael Buesch <mb@bu3sch.de>
Acked-by: Marcel Holtmann <marcel@holtmann.org> (for drivers/bluetooth/)
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

After pcmcia_request_io(), do not make use of the values stored in
io_req_t, but instead use those found in struct pcmcia_device->resource[].

CC: netdev@vger.kernel.org
CC: linux-wireless@vger.kernel.org
CC: linux-ide@vger.kernel.org
CC: linux-usb@vger.kernel.org
CC: laforge@gnumonks.org
CC: linux-mtd@lists.infradead.org
CC: alsa-devel@alsa-project.org
CC: linux-serial@vger.kernel.org
Acked-by: Marcel Holtmann <marcel@holtmann.org> (for drivers/bluetooth/)
Signed-off-by: NDominik Brodowski <linux@dominikbrodowski.net>

Some BIOSes will claim a large chunk of stolen space.  Unless we
reclaim it, our aperture for remapping buffer objects will be
constrained.  So clamp the stolen space to 32M and ignore the rest.

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=15469 among others.

Adding the ignored stolen memory back into the general pool using the
memory hotplug code is left as an exercise for the reader.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NSimon Farnsworth <simon.farnsworth@onelan.com>
Tested-by: NArtem S. Tashkinov <t.artem@mailcity.com>
Signed-off-by: NEric Anholt <eric@anholt.net>