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  1. 25 Apr, 2013 34 commits
  3. 10 Apr, 2013 6 commits
    • Ben Hutchings's avatar
      Linux 3.2.43 · 93dfb878
      Ben Hutchings authored
      93dfb878
    • Jiri Slaby's avatar
      HID: microsoft: do not use compound literal - fix build · 1e8b82e5
      Jiri Slaby authored 
      commit 6b90466c upstream.

In patch "HID: microsoft: fix invalid rdesc for 3k kbd" I fixed
support for MS 3k keyboards. However the added check using memcmp and
a compound statement breaks build on architectures where memcmp is a
macro with parameters.

hid-microsoft.c:51:18: error: macro "memcmp" passed 6 arguments, but takes just 3

On x86_64, memcmp is a function, so I did not see the error.
Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      1e8b82e5
    • Veaceslav Falico's avatar
      bonding: get netdev_rx_handler_unregister out of locks · c5b444a3
      Veaceslav Falico authored 
      commit fcd99434 upstream.

Now that netdev_rx_handler_unregister contains synchronize_net(), we need
to call it outside of bond->lock, cause it might sleep. Also, remove the
already unneded synchronize_net().
Signed-off-by: default avatarVeaceslav Falico <vfalico@redhat.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      c5b444a3
    • Steve Glendinning's avatar
      smsc75xx: fix jumbo frame support · 51119124
      Steve Glendinning authored 
      [ Upstream commit 4c51e536 ]

This patch enables RX of jumbo frames for LAN7500.

Previously the driver would transmit jumbo frames succesfully but
would drop received jumbo frames (incrementing the interface errors
count).

With this patch applied the device can succesfully receive jumbo
frames up to MTU 9000 (9014 bytes on the wire including ethernet
header).
Signed-off-by: default avatarSteve Glendinning <steve.glendinning@shawell.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      51119124
    • Veaceslav Falico's avatar
      pch_gbe: fix ip_summed checksum reporting on rx · f13514fe
      Veaceslav Falico authored 
      [ Upstream commit 76a0e681 ]

skb->ip_summed should be CHECKSUM_UNNECESSARY when the driver reports that
checksums were correct and CHECKSUM_NONE in any other case. They're
currently placed vice versa, which breaks the forwarding scenario. Fix it
by placing them as described above.
Signed-off-by: default avatarVeaceslav Falico <vfalico@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      f13514fe
    • Eric Dumazet's avatar
      net: add a synchronize_net() in netdev_rx_handler_unregister() · d94b6028
      Eric Dumazet authored 
      [ Upstream commit 00cfec37 ]

commit 35d48903 (bonding: fix rx_handler locking) added a race
in bonding driver, reported by Steven Rostedt who did a very good
diagnosis :

<quoting Steven>

I'm currently debugging a crash in an old 3.0-rt kernel that one of our
customers is seeing. The bug happens with a stress test that loads and
unloads the bonding module in a loop (I don't know all the details as
I'm not the one that is directly interacting with the customer). But the
bug looks to be something that may still be present and possibly present
in mainline too. It will just be much harder to trigger it in mainline.

In -rt, interrupts are threads, and can schedule in and out just like
any other thread. Note, mainline now supports interrupt threads so this
may be easily reproducible in mainline as well. I don't have the ability
to tell the customer to try mainline or other kernels, so my hands are
somewhat tied to what I can do.

But according to a core dump, I tracked down that the eth irq thread
crashed in bond_handle_frame() here:

        slave = bond_slave_get_rcu(skb->dev);
        bond = slave->bond; <--- BUG

the slave returned was NULL and accessing slave->bond caused a NULL
pointer dereference.

Looking at the code that unregisters the handler:

void netdev_rx_handler_unregister(struct net_device *dev)
{

        ASSERT_RTNL();
        RCU_INIT_POINTER(dev->rx_handler, NULL);
        RCU_INIT_POINTER(dev->rx_handler_data, NULL);
}

Which is basically:
        dev->rx_handler = NULL;
        dev->rx_handler_data = NULL;

And looking at __netif_receive_skb() we have:

        rx_handler = rcu_dereference(skb->dev->rx_handler);
        if (rx_handler) {
                if (pt_prev) {
                        ret = deliver_skb(skb, pt_prev, orig_dev);
                        pt_prev = NULL;
                }
                switch (rx_handler(&skb)) {

My question to all of you is, what stops this interrupt from happening
while the bonding module is unloading?  What happens if the interrupt
triggers and we have this:

        CPU0                    CPU1
        ----                    ----
  rx_handler = skb->dev->rx_handler

                        netdev_rx_handler_unregister() {
                           dev->rx_handler = NULL;
                           dev->rx_handler_data = NULL;

  rx_handler()
   bond_handle_frame() {
    slave = skb->dev->rx_handler;
    bond = slave->bond; <-- NULL pointer dereference!!!

What protection am I missing in the bond release handler that would
prevent the above from happening?

</quoting Steven>

We can fix bug this in two ways. First is adding a test in
bond_handle_frame() and others to check if rx_handler_data is NULL.

A second way is adding a synchronize_net() in
netdev_rx_handler_unregister() to make sure that a rcu protected reader
has the guarantee to see a non NULL rx_handler_data.

The second way is better as it avoids an extra test in fast path.
Reported-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Jiri Pirko <jpirko@redhat.com>
Cc: Paul E. McKenney <paulmck@us.ibm.com>
Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Reviewed-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      d94b6028
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