11 Oct, 2007

1 commit

  • This patch passes in the namespace a new socket should be created in
    and has the socket code do the appropriate reference counting. By
    virtue of this all socket create methods are touched. In addition
    the socket create methods are modified so that they will fail if
    you attempt to create a socket in a non-default network namespace.

    Failing if we attempt to create a socket outside of the default
    network namespace ensures that as we incrementally make the network stack
    network namespace aware we will not export functionality that someone
    has not audited and made certain is network namespace safe.
    Allowing us to partially enable network namespaces before all of the
    exotic protocols are supported.

    Any protocol layers I have missed will fail to compile because I now
    pass an extra parameter into the socket creation code.

    [ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]

    Signed-off-by: Eric W. Biederman
    Signed-off-by: David S. Miller

    Eric W. Biederman
     

31 Jul, 2007

1 commit

  • Adrian Bunk wrote:
    > Commit 8de0a15483b357d0f0b821330ec84d1660cadc4e added the following
    > use-after-free in net/bluetooth/rfcomm/tty.c:
    >
    >
    >
    > ...
    > static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
    > {
    > ...
    > if (IS_ERR(dev->tty_dev)) {
    > list_del(&dev->list);
    > kfree(dev);
    > return PTR_ERR(dev->tty_dev);
    > }
    > ...
    >
    >
    >
    > Spotted by the Coverity checker.

    really good catch. I fully overlooked that one. The attached patch
    should fix it.

    Signed-off-by: Marcel Holtmann
    Signed-off-by: David S. Miller

    Marcel Holtmann
     

18 Jul, 2007

1 commit

  • Currently, the freezer treats all tasks as freezable, except for the kernel
    threads that explicitly set the PF_NOFREEZE flag for themselves. This
    approach is problematic, since it requires every kernel thread to either
    set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
    care for the freezing of tasks at all.

    It seems better to only require the kernel threads that want to or need to
    be frozen to use some freezer-related code and to remove any
    freezer-related code from the other (nonfreezable) kernel threads, which is
    done in this patch.

    The patch causes all kernel threads to be nonfreezable by default (ie. to
    have PF_NOFREEZE set by default) and introduces the set_freezable()
    function that should be called by the freezable kernel threads in order to
    unset PF_NOFREEZE. It also makes all of the currently freezable kernel
    threads call set_freezable(), so it shouldn't cause any (intentional)
    change of behaviour to appear. Additionally, it updates documentation to
    describe the freezing of tasks more accurately.

    [akpm@linux-foundation.org: build fixes]
    Signed-off-by: Rafael J. Wysocki
    Acked-by: Nigel Cunningham
    Cc: Pavel Machek
    Cc: Oleg Nesterov
    Cc: Gautham R Shenoy
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Rafael J. Wysocki
     

11 Jul, 2007

2 commits


05 May, 2007

3 commits


26 Apr, 2007

2 commits

  • Set TASK_INTERRUPTIBLE prior to testing the flag to avoid missed wakeups.

    Signed-off-by: Andrew Morton
    Acked-by: Marcel Holtmann
    Signed-off-by: David S. Miller

    Andrew Morton
     
  • So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
    on 64bit architectures, allowing us to combine the 4 bytes hole left by the
    layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
    64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
    :-)

    Many calculations that previously required that skb->{transport,network,
    mac}_header be first converted to a pointer now can be done directly, being
    meaningful as offsets or pointers.

    Signed-off-by: Arnaldo Carvalho de Melo
    Signed-off-by: David S. Miller

    Arnaldo Carvalho de Melo
     

27 Feb, 2007

1 commit


11 Feb, 2007

1 commit


09 Jan, 2007

2 commits


09 Dec, 2006

1 commit

  • This is the grungy swap all the occurrences in the right places patch that
    goes with the updates. At this point we have the same functionality as
    before (except that sgttyb() returns speeds not zero) and are ready to
    begin turning new stuff on providing nobody reports lots of bugs

    If you are a tty driver author converting an out of tree driver the only
    impact should be termios->ktermios name changes for the speed/property
    setting functions from your upper layers.

    If you are implementing your own TCGETS function before then your driver
    was broken already and its about to get a whole lot more painful for you so
    please fix it 8)

    Also fill in c_ispeed/ospeed on init for most devices, although the current
    code will do this for you anyway but I'd like eventually to lose that extra
    paranoia

    [akpm@osdl.org: bluetooth fix]
    [mp3@de.ibm.com: sclp fix]
    [mp3@de.ibm.com: warning fix for tty3270]
    [hugh@veritas.com: fix tty_ioctl powerpc build]
    [jdike@addtoit.com: uml: fix ->set_termios declaration]
    Signed-off-by: Alan Cox
    Signed-off-by: Martin Peschke
    Acked-by: Peter Oberparleiter
    Cc: Cornelia Huck
    Signed-off-by: Hugh Dickins
    Signed-off-by: Jeff Dike
    Cc: Paolo 'Blaisorblade' Giarrusso
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     

03 Dec, 2006

2 commits


22 Nov, 2006

1 commit


16 Oct, 2006

4 commits


02 Oct, 2006

1 commit

  • As part of an SMP cleanliness pass over UML, I consted a bunch of
    structures in order to not have to document their locking. One of these
    structures was a struct tty_operations. In order to const it in UML
    without introducing compiler complaints, the declaration of
    tty_set_operations needs to be changed, and then all of its callers need to
    be fixed.

    This patch declares all struct tty_operations in the tree as const. In all
    cases, they are static and used only as input to tty_set_operations. As an
    extra check, I ran an i386 allyesconfig build which produced no extra
    warnings.

    53 drivers are affected. I checked the history of a bunch of them, and in
    most cases, there have been only a handful of maintenance changes in the
    last six months. serial_core.c was the busiest one that I looked at.

    Signed-off-by: Jeff Dike
    Acked-by: Alan Cox
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jeff Dike
     

29 Sep, 2006

2 commits


25 Jul, 2006

1 commit

  • Some Bluetooth RFCOMM implementations try to negotiate a bigger channel
    MTU than we can support for a particular session. The maximum MTU for
    a RFCOMM session is limited through the L2CAP layer. So if the other
    side proposes a channel MTU that is bigger than the underlying L2CAP
    MTU, we should reduce it to the L2CAP MTU of the session minus five
    bytes for the RFCOMM headers.

    Signed-off-by: Marcel Holtmann

    Marcel Holtmann
     

13 Jul, 2006

1 commit


04 Jul, 2006

3 commits


01 Jul, 2006

1 commit


30 Jun, 2006

1 commit

  • * git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/devfs-2.6: (22 commits)
    [PATCH] devfs: Remove it from the feature_removal.txt file
    [PATCH] devfs: Last little devfs cleanups throughout the kernel tree.
    [PATCH] devfs: Rename TTY_DRIVER_NO_DEVFS to TTY_DRIVER_DYNAMIC_DEV
    [PATCH] devfs: Remove the tty_driver devfs_name field as it's no longer needed
    [PATCH] devfs: Remove the line_driver devfs_name field as it's no longer needed
    [PATCH] devfs: Remove the videodevice devfs_name field as it's no longer needed
    [PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
    [PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed
    [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
    [PATCH] devfs: Remove devfs_remove() function from the kernel tree
    [PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
    [PATCH] devfs: Remove devfs_mk_bdev() function from the kernel tree
    [PATCH] devfs: Remove devfs_mk_symlink() function from the kernel tree
    [PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
    [PATCH] devfs: Remove devfs_*_tape() functions from the kernel tree
    [PATCH] devfs: Remove devfs support from the sound subsystem
    [PATCH] devfs: Remove devfs support from the ide subsystem.
    [PATCH] devfs: Remove devfs support from the serial subsystem
    [PATCH] devfs: Remove devfs from the init code
    [PATCH] devfs: Remove devfs from the partition code
    ...

    Linus Torvalds
     

29 Jun, 2006

1 commit

  • Remove TTY_DONT_FLIP tty flag. This flag was introduced in 2.1.X kernels
    to prevent the N_TTY line discipline functions read_chan() and
    n_tty_receive_buf() from running at the same time. 2.2.15 introduced
    tty->read_lock to protect access to the N_TTY read buffer, which is the
    only state requiring protection between these two functions.

    The current TTY_DONT_FLIP implementation is broken for SMP, and is not
    universally honored by drivers that send data directly to the line
    discipline receive_buf function.

    Because TTY_DONT_FLIP is not necessary, is broken in implementation, and is
    not universally honored, it is removed.

    Signed-off-by: Paul Fulghum
    Cc: Alan Cox
    Cc: Theodore Ts'o
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Paul Fulghum
     

27 Jun, 2006

2 commits


21 Mar, 2006

1 commit

  • Semaphore to mutex conversion.

    The conversion was generated via scripts, and the result was validated
    automatically via a script as well.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Ingo Molnar
    Signed-off-by: Andrew Morton
    Signed-off-by: David S. Miller

    Arjan van de Ven
     

13 Feb, 2006

1 commit


12 Jan, 2006

1 commit


11 Jan, 2006

1 commit

  • The API and code have been through various bits of initial review by
    serial driver people but they definitely need to live somewhere for a
    while so the unconverted drivers can get knocked into shape, existing
    drivers that have been updated can be better tuned and bugs whacked out.

    This replaces the tty flip buffers with kmalloc objects in rings. In the
    normal situation for an IRQ driven serial port at typical speeds the
    behaviour is pretty much the same, two buffers end up allocated and the
    kernel cycles between them as before.

    When there are delays or at high speed we now behave far better as the
    buffer pool can grow a bit rather than lose characters. This also means
    that we can operate at higher speeds reliably.

    For drivers that receive characters in blocks (DMA based, USB and
    especially virtualisation) the layer allows a lot of driver specific
    code that works around the tty layer with private secondary queues to be
    removed. The IBM folks need this sort of layer, the smart serial port
    people do, the virtualisers do (because a virtualised tty typically
    operates at infinite speed rather than emulating 9600 baud).

    Finally many drivers had invalid and unsafe attempts to avoid buffer
    overflows by directly invoking tty methods extracted out of the innards
    of work queue structs. These are no longer needed and all go away. That
    fixes various random hangs with serial ports on overflow.

    The other change in here is to optimise the receive_room path that is
    used by some callers. It turns out that only one ldisc uses receive room
    except asa constant and it updates it far far less than the value is
    read. We thus make it a variable not a function call.

    I expect the code to contain bugs due to the size alone but I'll be
    watching and squashing them and feeding out new patches as it goes.

    Because the buffers now dynamically expand you should only run out of
    buffering when the kernel runs out of memory for real. That means a lot of
    the horrible hacks high performance drivers used to do just aren't needed any
    more.

    Description:

    tty_insert_flip_char is an old API and continues to work as before, as does
    tty_flip_buffer_push() [this is why many drivers dont need modification]. It
    does now also return the number of chars inserted

    There are also

    tty_buffer_request_room(tty, len)

    which asks for a buffer block of the length requested and returns the space
    found. This improves efficiency with hardware that knows how much to
    transfer.

    and tty_insert_flip_string_flags(tty, str, flags, len)

    to insert a string of characters and flags

    For a smart interface the usual code is

    len = tty_request_buffer_room(tty, amount_hardware_says);
    tty_insert_flip_string(tty, buffer_from_card, len);

    More description!

    At the moment tty buffers are attached directly to the tty. This is causing a
    lot of the problems related to tty layer locking, also problems at high speed
    and also with bursty data (such as occurs in virtualised environments)

    I'm working on ripping out the flip buffers and replacing them with a pool of
    dynamically allocated buffers. This allows both for old style "byte I/O"
    devices and also helps virtualisation and smart devices where large blocks of
    data suddenely materialise and need storing.

    So far so good. Lots of drivers reference tty->flip.*. Several of them also
    call directly and unsafely into function pointers it provides. This will all
    break. Most drivers can use tty_insert_flip_char which can be kept as an API
    but others need more.

    At the moment I've added the following interfaces, if people think more will
    be needed now is a good time to say

    int tty_buffer_request_room(tty, size)

    Try and ensure at least size bytes are available, returns actual room (may be
    zero). At the moment it just uses the flipbuf space but that will change.
    Repeated calls without characters being added are not cumulative. (ie if you
    call it with 1, 1, 1, and then 4 you'll have four characters of space. The
    other functions will also try and grow buffers in future but this will be a
    more efficient way when you know block sizes.

    int tty_insert_flip_char(tty, ch, flag)

    As before insert a character if there is room. Now returns 1 for success, 0
    for failure.

    int tty_insert_flip_string(tty, str, len)

    Insert a block of non error characters. Returns the number inserted.

    int tty_prepare_flip_string(tty, strptr, len)

    Adjust the buffer to allow len characters to be added. Returns a buffer
    pointer in strptr and the length available. This allows for hardware that
    needs to use functions like insl or mencpy_fromio.

    Signed-off-by: Alan Cox
    Cc: Paul Fulghum
    Signed-off-by: Hirokazu Takata
    Signed-off-by: Serge Hallyn
    Signed-off-by: Jeff Dike
    Signed-off-by: John Hawkes
    Signed-off-by: Martin Schwidefsky
    Signed-off-by: Adrian Bunk
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Alan Cox
     

04 Jan, 2006

1 commit

  • I noticed that some of 'struct proto_ops' used in the kernel may share
    a cache line used by locks or other heavily modified data. (default
    linker alignement is 32 bytes, and L1_CACHE_LINE is 64 or 128 at
    least)

    This patch makes sure a 'struct proto_ops' can be declared as const,
    so that all cpus can share all parts of it without false sharing.

    This is not mandatory : a driver can still use a read/write structure
    if it needs to (and eventually a __read_mostly)

    I made a global stubstitute to change all existing occurences to make
    them const.

    This should reduce the possibility of false sharing on SMP, and
    speedup some socket system calls.

    Signed-off-by: Eric Dumazet
    Signed-off-by: David S. Miller

    Eric Dumazet