net: more accurate skb truesize

skb truesize currently accounts for sk_buff struct and part of skb head.
kmalloc() roundings are also ignored.

Considering that skb_shared_info is larger than sk_buff, its time to
take it into account for better memory accounting.

This patch introduces SKB_TRUESIZE(X) macro to centralize various
assumptions into a single place.

At skb alloc phase, we put skb_shared_info struct at the exact end of
skb head, to allow a better use of memory (lowering number of
reallocations), since kmalloc() gives us power-of-two memory blocks.

Unless SLUB/SLUB debug is active, both skb->head and skb_shared_info are
aligned to cache lines, as before.

Note: This patch might trigger performance regressions because of
misconfigured protocol stacks, hitting per socket or global memory
limits that were previously not reached. But its a necessary step for a
more accurate memory accounting.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Andi Kleen <ak@linux.intel.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Allow skb_recycle_check to be done in stages

skb_recycle_check resets the skb if it's eligible for recycling.
However, there are times when a driver might want to optionally
manipulate the skb data with the skb before resetting the skb,
but after it has determined eligibility.  We do this by splitting the
eligibility check from the skb reset, creating two inline functions to
accomplish that task.

Signed-off-by: Andy Fleming <afleming@freescale.com>
Acked-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
usb: core: driver: fixup when building for endeavoru
patch: fix nct1008 regulator for endeavoru
wl12xx: fix sdio out-of-sync power state
board-endeavoru-sdhci: reenable .built_in
board-endeavoru-sdhci: introduce .ocr_mask
patch: enable gpu oc 484mhz
tlv320aic3008: remove votecpuminfreq
tlv320aic3008: support PCM_FMTBIT_S32_LE
config: update tripndroid jellybean config 004A
mm, oom: fix potential killing of thread that is disabled from oom killing

/proc/sys/vm/oom_kill_allocating_task will immediately kill current when
the oom killer is called to avoid a potentially expensive tasklist scan
for large systems.

Currently, however, it is not checking current's oom_score_adj value
which may be OOM_SCORE_ADJ_MIN, meaning that it has been disabled from
oom killing.

This patch avoids killing current in such a condition and simply falls
back to the tasklist scan since memory still needs to be freed.

Signed-off-by: David Rientjes <rientjes@google.com>
backported from Linux 3.5 to linux 2.6.39 by faux123
fifo: Do not restart open() if it already found a partner
If a parent and child process open the two ends of a fifo, and the
child immediately exits, the parent may receive a SIGCHLD before its
open() returns.  In that case, we need to make sure that open() will
return successfully after the SIGCHLD handler returns, instead of
throwing EINTR or being restarted.  Otherwise, the restarted open()
would incorrectly wait for a second partner on the other end.

The following test demonstrates the EINTR that was wrongly thrown from
the parent.s open().  Change .sa_flags = 0 to .sa_flags = SA_RESTART
to see a deadlock instead, in which the restarted open() waits for a
second reader that will never come.

  #include <sys/stat.h>
  #include <sys/types.h>
  #include <sys/wait.h>
  #include <fcntl.h>
  #include <signal.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>

  #define CHECK(x) do {if ((x) == -1) {perror(#x); abort();}} while(0)
  void handler(int signum) {}
  int main()
  {
      struct sigaction act = {.sa_handler = handler, .sa_flags = 0};
      CHECK(sigaction(SIGCHLD, &act, NULL));
      CHECK(mknod("fifo", S_IFIFO | S_IRWXU, 0));
      for (;;) {
          int fd;
          pid_t pid;
          putc('.', stderr);
          CHECK(pid = fork());
          if (pid == 0) {
              CHECK(fd = open("fifo", O_RDONLY));
              _exit(0);
          }
          CHECK(fd = open("fifo", O_WRONLY));
          CHECK(close(fd));
          CHECK(waitpid(pid, NULL, 0));
      }
  }
This is what I suspect was causing the Git test suite to fail in
t9010-svn-fe.sh:
http://bugs.debian.org/678852

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
backported to Linux 2.6.39 from Linux 3.5+ by faux123
block: fix infinite loop in __getblk_slow
Hi,

This commit:

commit 080399a
Author: Jeff Moyer <jmoyer@redhat.com>
Date:   Fri May 11 16:34:10 2012 +0200

    block: don't mark buffers beyond end of disk as mapped

exposed a bug in __getblk_slow that causes mount to hang as it loops
infinitely waiting for a buffer that lies beyond the end of the disk to
become uptodate.  The problem was initially reported by Torsten Hilbrich
here: https://lkml.org/lkml/2012/6/18/54, and also reported
independently here:
http://www.sysresccd.org/forums/viewtopic.php?f=13&t=4511, and then
Richard W.M. Jones and Marcos Mello noted a few separate bugzillas also
associated with the same issue.

The main problem is here, in __getblk_slow:

        for (;;) {
                struct buffer_head * bh;
                int ret;
                bh = __find_get_block(bdev, block, size);
                if (bh)
                        return bh;
                ret = grow_buffers(bdev, block, size);
                if (ret < 0)
                        return NULL;
                if (ret == 0)
                        free_more_memory();
        }
__find_get_block does not find the block, since it will not be marked as
mapped, and so grow_buffers is called to fill in the buffers for the
associated page.  I believe the for (;;) loop is there primarily to
retry in the case of memory pressure keeping grow_buffers from
succeeding.  However, we also continue to loop for other cases, like the
block lying beond the end of the disk.  So, the fix I came up with is to
only loop when grow_buffers fails due to memory allocation issues
(return value of 0).

The attached patch was tested by myself, Torsten, and Rich, and was
found to resolve the problem in call cases.

Comments, as always, are appreciated.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Reported-and-Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Cc: Stable <stable@vger.kernel.org>
backported from Linux 3.5+ to Linux 2.6.39 by faux123
sched: task_times() explosion avoidance for tasks with > 2^32 acrued ticks

If stime + utime > 2^32, and lower 32 are 0 when user calls getrusage(),
you've got a dead box.
Signed-off-by: Mike Galbraith <efault@gmx.de>
backported from Linux 3.5+ to Linux 3.0 by faux123
sched,rt: fix isolated CPUs leaving root_task_group indefinitely throttled

Speaking of old "parches" lying about, the below fixes a real problem if
you're using either 'should die' isolcpus or 'should work' cpusets to
isolate cores.

sched,rt: fix isolated CPUs leaving root_task_group indefinitely throttled

Root task group bandwidth replenishment must service all CPUs, regardless of
where the timer was last started, and regardless of the isolation mechanism,
lest 'Quoth the Raven, "Nevermore"' become rt scheduling policy.

Signed-off-by: Mike Galbraith <efault@gmx.de>
backported from Linux 3.5+ to linux 3.0 by faux123
patch: update wifi drivers (unfinished) 01
patch: complete the previous wifi patch (working)
patch: wifi update 3 (internal)
nl80211: fix MAC address validation

MAC addresses have a fixed length. The current
policy allows passing < ETH_ALEN bytes, which
might result in reading beyond the buffer.

Cc: stable@vger.kernel.org
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>