efivars: check for EFI_RUNTIME_SERVICES

The efivars code requires EFI runtime services to function, so check
that they are enabled.

This fixes a crash when booting with the "noefi" kernel parameter, and
also when mixing kernel and firmware "bitness", e.g. 32-bit kernel with
64-bit firmware.

Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Revert "UEFI: Don't pass boot services regions to SetVirtualAddressMap()"

This reverts commit 1acba98f810a14b1255e34bc620594f83de37e36.

The firmware on both Dave's Thinkpad and Maarten's Macbook Pro appear to
rely on the old behaviour, and their machines fail to boot with the
above commit.

Reported-by: Dave Young <dyoung@redhat.com>
Reported-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Seth Forshee <seth.forshee@canonical.com>
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
x86/platform/ce4100: Add header file for reboot type

Add header file for reboot type to fix this build failure:

 error: 'reboot_type' undeclared (first use in this function)
 error: 'BOOT_KBD' undeclared (first use in this function)

Signed-off-by: Xiong Zhou <jencce.kernel@gmail.com>
Cc: rui.zhang@intel.com
Cc: alan@linux.intel.com
Cc: ffainelli@freebox.fr
Cc: mbizon@freebox.fr
Cc: matthew.garrett@nebula.com
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1307091053280.28371@M2420
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86, suspend: Handle CPUs which fail to #GP on RDMSR

There are CPUs which have errata causing RDMSR of a nonexistent MSR to
not fault.  We would then try to WRMSR to restore the value of that
MSR, causing a crash.  Specifically, some Pentium M variants would
have this problem trying to save and restore the non-existent EFER,
causing a crash on resume.

Work around this by making sure we can write back the result at
suspend time.

Huge thanks to Christian Sünkenberg for finding the offending erratum
that finally deciphered the mystery.

Reported-and-tested-by: Johan Heinrich <onny@project-insanity.org>
Debugged-by: Christian Sünkenberg <christian.suenkenberg@student.kit.edu>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Link: http://lkml.kernel.org/r/51DDC972.3010005@student.kit.edu
Cc: <stable@vger.kernel.org> # v3.7+
x86: Make sure IDT is page aligned

Since the IDT is referenced from a fixmap, make sure it is page aligned.
Merge with 32-bit one, since it was already aligned to deal with F00F
bug. Since bss is cleared before IDT setup, it can live there. This also
moves the other *_idt_table variables into common locations.

This avoids the risk of the IDT ever being moved in the bss and having
the mapping be offset, resulting in calling incorrect handlers. In the
current upstream kernel this is not a manifested bug, but heavily patched
kernels (such as those using the PaX patch series) did encounter this bug.

The tables other than idt_table technically do not need to be page
aligned, at least not at the current time, but using a common
declaration avoids mistakes.  On 64 bits the table is exactly one page
long, anyway.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20130716183441.GA14232@www.outflux.net
Reported-by: PaX Team <pageexec@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
md/raid10: fix two problems with RAID10 resync.

1/ When an different between blocks is found, data is copied from
   one bio to the other.  However bv_len is used as the length to
   copy and this could be zero.  So use r10_bio->sectors to calculate
   length instead.
   Using bv_len was probably always a bit dubious, but the introduction
   of bio_advance made it much more likely to be a problem.

2/ When preparing some blocks for sync, we don't set BIO_UPTODATE
   except on bios that we schedule for a read.  This ensures that
   missing/failed devices don't confuse the loop at the top of
   sync_request write.
   Commit 8be185f2c9d54d6 "raid10: Use bio_reset()"
   removed a loop which set BIO_UPTDATE on all appropriate bios.
   So we need to re-add that flag.

These bugs were introduced in 3.10, so this patch is suitable for
3.10-stable, and can remove a potential for data corruption.

Cc: stable@vger.kernel.org (3.10)
Reported-by: Brassow Jonathan <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
md: Remove recent change which allows devices to skip recovery.

commit 7ceb17e87bde79d285a8b988cfed9eaeebe60b86
    md: Allow devices to be re-added to a read-only array.

allowed a bit more than just that.  It also allows devices to be added
to a read-write array and to end up skipping recovery.

This patch removes the offending piece of code pending a rewrite for a
subsequent release.

More specifically:
 If the array has a bitmap, then the device will still need a bitmap
 based resync ('saved_raid_disk' is set under different conditions
 is a bitmap is present).
 If the array doesn't have a bitmap, then this is correct as long as
 nothing has been written to the array since the metadata was checked
 by ->validate_super.  However there is no locking to ensure that there
 was no write.

Bug was introduced in 3.10 and causes data corruption so
patch is suitable for 3.10-stable.

Cc: stable@vger.kernel.org (3.10)
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
md/raid1: fix bio handling problems in process_checks()

Recent change to use bio_copy_data() in raid1 when repairing
an array is faulty.

The underlying may have changed the bio in various ways using
bio_advance and these need to be undone not just for the 'sbio' which
is being copied to, but also the 'pbio' (primary) which is being
copied from.

So perform the reset on all bios that were read from and do it early.

This also ensure that the sbio->bi_io_vec[j].bv_len passed to
memcmp is correct.

This fixes a crash during a 'check' of a RAID1 array.  The crash was
introduced in 3.10 so this is suitable for 3.10-stable.

Cc: stable@vger.kernel.org (3.10)
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Merge tag 'md-3.11-fixes' of git://neil.brown.name/md

Pull md bug fixes from NeilBrown:
 "Sorry boss, back at work now boss.  Here's them nice shiny patches ya
  wanted.  All nicely tagged and justified for -stable and everyfing:

  Three bug fixes for md in 3.10

  3.10 wasn't a good release for md.  The bio changes left a couple of
  bugs, and an md "fix" created another one.

  These three patches appear to fix the issues and have been tagged for
  -stable"

* tag 'md-3.11-fixes' of git://neil.brown.name/md:
  md/raid1: fix bio handling problems in process_checks()
  md: Remove recent change which allows devices to skip recovery.
  md/raid10: fix two problems with RAID10 resync.
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Trying again to get the fixes queue, including the fixed IDT alignment
  patch.

  The UEFI patch is by far the biggest issue at hand: it is currently
  causing quite a few machines to boot.  Which is sad, because the only
  reason they would is because their BIOSes touch memory that has
  already been freed.  The other major issue is that we finally have
  tracked down the root cause of a significant number of machines
  failing to suspend/resume"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Make sure IDT is page aligned
  x86, suspend: Handle CPUs which fail to #GP on RDMSR
  x86/platform/ce4100: Add header file for reboot type
  Revert "UEFI: Don't pass boot services regions to SetVirtualAddressMap()"
  efivars: check for EFI_RUNTIME_SERVICES