Merge tag 'stable/for-linus-3.14-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen fix from Konrad Rzeszutek Wilk:
 "This has exactly one patch for Xen ARM.  It sets the dependency to
  compile the kernel with MMU enabled - otherwise - the guest won't work
  very well"

* tag 'stable/for-linus-3.14-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  ARM: XEN depends on having a MMU
Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 - a bugfix for a long standing waitqueue race
 - a trivial fix for a missing include

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Include missing header file in irqdomain.c
  genirq: Remove racy waitqueue_active check

Conflicts:
	kernel/irq/irqdomain.c
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "A small collection of minor fixes.  The FPU stuff is still pending, I
  fear.  I haven't heard anything from Suresh so I suspect I'm going to
  have to dig into the init specifics myself and fix up the patchset"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Ignore NMIs that come in during early boot
  x86, trace: Further robustify CR2 handling vs tracing
  x86, trace: Fix CR2 corruption when tracing page faults
  x86/efi: Quirk out SGI UV

Conflicts:
	arch/x86/include/asm/efi.h
	arch/x86/kernel/head_32.S
	arch/x86/kernel/head_64.S
	arch/x86/platform/efi/efi.c
Merge tag 'usb-3.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are 4 USB fixes for your current tree.

  Two of them are reverts to hopefully resolve the nasty XHCI
  regressions we have been having on some types of devices.  The other
  two are quirks for some Logitech video devices"

* tag 'usb-3.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  Revert "USBNET: ax88179_178a: enable tso if usb host supports sg dma"
  Revert "xhci 1.0: Limit arbitrarily-aligned scatter gather."
  usb: Make DELAY_INIT quirk wait 100ms between Get Configuration requests
  usb: Add device quirk for Logitech HD Pro Webcams C920 and C930e

Conflicts:
	drivers/usb/core/quirks.c
	drivers/usb/host/xhci.c
vfs: atomic f_pos accesses as per POSIX

Our write() system call has always been atomic in the sense that you get
the expected thread-safe contiguous write, but we haven't actually
guaranteed that concurrent writes are serialized wrt f_pos accesses, so
threads (or processes) that share a file descriptor and use "write()"
concurrently would quite likely overwrite each others data.

This violates POSIX.1-2008/SUSv4 Section XSI 2.9.7 that says:

 "2.9.7 Thread Interactions with Regular File Operations

  All of the following functions shall be atomic with respect to each
  other in the effects specified in POSIX.1-2008 when they operate on
  regular files or symbolic links: [...]"

and one of the effects is the file position update.

This unprotected file position behavior is not new behavior, and nobody
has ever cared.  Until now.  Yongzhi Pan reported unexpected behavior to
Michael Kerrisk that was due to this.

This resolves the issue with a f_pos-specific lock that is taken by
read/write/lseek on file descriptors that may be shared across threads
or processes.

Reported-by: Yongzhi Pan <panyongzhi@gmail.com>
Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Conflicts:
	fs/read_write.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs fixes from Al Viro.

Clean up file table accesses (get rid of fget_light() in favor of the
fdget() interface), add proper file position locking.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  get rid of fget_light()
  sockfd_lookup_light(): switch to fdget^W^Waway from fget_light
  vfs: atomic f_pos accesses as per POSIX
  ocfs2 syncs the wrong range...

Conflicts:
	fs/file.c
	fs/read_write.c